P/N 0153180July 1999
P.O. Box 1160 St. Joseph, MO 64502-11601-800-255-0317 Fax: 816-360-9379
www.snorkelusa.com
TroubleshootingGuide
1
GENERAL INFORMATIONThis manual contains procedures for locating and correcting the majority of problems which maydevelop on the “Snorkelift” UNO 33 and 41 4x4 Aerial Platforms.
Since the majority of malfunctions experienced on equipment in the aerial platform Industry areassociated with the hydraulic and electrical systems, great effort has been made to develop a guidewhich insures that procedures regarding these areas are given the fullest possible attention and detail.As a result of these efforts, the aerial platform has been divided into twelve distinct groups with eachgroup covered by an individual section. The Sections are as follows:
1.) Engine Diagnostics 7.) Boom Functions Diagnostics2.) Hydraulic Diagnostics 8.) Platform Leveling System Diagnostics3.) Steering System Diagnostics 9.) Boom Elevation System Diagnostics4.) Drive System Diagnostics 10.) Telescope System Diagnostics5.) Emergency Power System Diagnostics 11.) Fuel System Diagnostics6.) Swing System Diagnostics 12.) Accessories Diagnostics
NOTES, CAUTIONS AND DANGERSThe terms NOTE, CAUTION, and DANGER appear throughout this manual and have specific mean-ings.
A NOTE provides additional or special information to make a step or procedure easier orclearer. Disregarding a NOTE might cause inconvenience, but would not cause equipment damage orpersonal injury.
A is provided in a procedure wherever minor personal injury or equipmentdamage could result. Disregarding a CAUTION could cause damage to the machine; however seriouspersonal injury is unlikely.
is the most serious and emphasizes areas where personnel injury and evendeath could result from negligence. Permanent mechanical damage is also highly probable. DANGERsigns are to be taken seriously. In some cases, serious injury or death has resulted from disregardinga DANGER.
NOTE: Engine maintenance and troubleshooting information not contained in this manual may befound in the engine maintenance manual originally provided with the machine, or from the EngineManufacture/Dealer Network.
It should be recognized that every person who performs testing and diagnostic procedures and everyperson supervising any of these functions must be properly trained and qualified. If a problem shouldoccur which is not covered by this manual or which cannot be corrected using the listed correctiveactions, technically qualified guidance from the Service Department of Snorkel International Inc.,should be obtained prior to proceeding further. Tel: (816) 364-0317
NOTE: Diagnostic procedures basically consist of a logical process of elimination. For this reason,it is very important that the steps be performed in the order in which they are presented. Always beginby localizing the problem and defining the symptoms as accurately as possible. When the problem hasbeen localized, make sure to completely read and comprehend the appropriate flow chart. Do notattempt to make shortcuts.
2
MANUAL DESIGN
Each symptom described is followed by a list of inspections to be performed. Each inspection is in theform of a flowchart. A set of detailed checks are then performed at the component and/or related areaswhich confirm or decline the outcome. If the inspection is declined the flowchart will refer to the nextstep to be performed until the problem is confirmed. The diagnosis then enables a determination.
Problem Go to PageInspect
Go to PageInspect
OK
Step 1
Step 2
Example: Problem Solving Procedure
Inspect
Troubleshoot(Identify Problem)
Replace orperform repair
If
Go to step
no
Yes
Example: Flowchart Procedure
EQUIPMENT NEEDED:Multimeter: A meter designed to read voltage, amperage and resistance.
Pressure Test Gauge: A pressure gauge rated for 0 - 1000 psi.
A pressure gauge rated for 0 - 5000 psi.
Tachometer: A meter designed to measure engine RPM on gas and/or diesel.
(Photo Tachometer is recommended)
Flowmeter: A meter designed to measure fluid flow.
Stopwatch: A tool designed to measure time.
3
SYMPTOM PAGE NUMBER
Section One - Engine DiagnosticsEngine starter fails to operate (No Electrical) 9Starter disengages before engine starts (Ford only) 10Engine cranks over but will not start 10Engine starts then shuts down after 30 seconds 11Engine will not accelerate (Ford only) 11Engine will not accelerate (Kubota only) 11Engine over accelerates (Ford only) 12Engine will not start from platform control 12Engine starts while cranking, then dies when key switch is released 13
Section Two - Hydraulic DiagnosticsHydraulic system functions on emergency power only 39Hydraulic pump stays on stroke 39Hydraulic functions are sluggish 39Hydraulic pump will not build pressure 39Hydraulic pump will not build enough pressure 40Flow from hydraulic pump is too low 40Flow from hydraulic pump is too high (kills engine) 40
Section Three - Steering System DiagnosticsMachine will not steer 51
4
SYMPTOM PAGE NUMBER
Section Four - Drive System DiagnosticsDrive system is not operational with controller in either direction 57No forward drive (reverse ok) 58No reverse drive (forward ok) 58Drive high range not operating (mid speed ok) 59Drive mid range not operating (low speed ok) 59Wheel on one side rotate faster than wheels on other side 59One wheel rotates slower than others 60Brakes will not release 60
Section Five - Emergency Power System DiagnosticsEmergency pump motor non-operational 83No functions when on emergency power 83
Section Six - Swing System DiagnosticsSwings only in one direction 89No response from swing when platform controls are activated (ground controls ok) 89No response from swing when ground controls are activated (platform controls ok) 89Swings erratically in either direction 90Swings faster one way than other 90Swing brake will not hold 90Swings too slow 91
Section Seven - Boom Functions DiagnosticsNo boom functions from ground control 107No boom functions from platform control 107
5
SYMPTOM PAGE NUMBER
Section Eight - Platform Leveling System DiagnosticsPlatform will not maintain level as boom raises or lowers 115Platform will not maintain level with machine off 115Platform level will not work from ground control (platform control ok) 115Platform level will not work from platform control (ground control ok) 115Platform level up function is inoperative 116Platform level down function is inoperative 116
Section Nine - Boom Elevation System DiagnosticsBoom raises but will not stay elevated (Bottom/Middle/Top) 127Bottom boom will not raise from platform control (ground control ok) 127Middle boom will not raise from platform control (ground control ok) (Uno 41 only) 127Top boom will not raise from platform control (ground control ok) 127Bottom boom will not raise from ground control 128Middle boom will not raise from ground control (Uno 41 only) 128Top boom will not raise from ground control 128
Section Ten - Telescope System DiagnosticsBoom will not retract from ground control 143Boom will not retract from platform control (ground control ok) 143Boom will not extend from ground control 144Boom will not extend from platform control (ground control ok) 144Boom drifts in 144
Section Eleven - Fuel System DiagnosticsEngine will not start on gasoline, but will start on L.P. 159Engine will not start on L.P., but will start on gasoline 159
6
SYMPTOM PAGE NUMBER
Section Twelve - Accessories DiagnosticsAC Generator will not function 167AC Generator has low voltage 167Machine will not steer 167
SECTION ONE:ENGINE DIAGNOSTICS
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 9 UNO 33/ 41 4X4
InspectStarter Solenoid
InspectPower Cables and
Battery Disconnect Switch
InspectGround Control
Circuit Breaker (25 Amp)
InspectEmergency Stop Switch
InspectGround Master (Key) Switch
InspectEngine Starter Relay
InspectIgnition/Emergency
Power Switch
InspectGround/PlatformSelector Switch
InspectEngine Anti-Restart Relay
(Ford Only)
Engine starterfails to operate(No Electrical)
Go to Page13
InspectBattery and Cable Connections
Go to Page13
Go to Page14
Go to Page15
Go to Page15
Go to Page16
Go to Page16
Go to Page17
Go to Page17
Go to Page18
OK
OK
OK
OK
OK
OK
OK
OK
OK
Chart 1
Step 1
Step 2
Step 4
Step 5
Step 6
Step 7
Step 8
Step 9
Step 10
Step 11
InspectAmmeter
Go to Page14
OKStep 3
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 10 UNO 33/ 41 4X4
Starterdisengages before
engine starts(Ford Only)
Go to Page19
InspectEngine Anti-Restart Relay
Engine cranksover but
will not startGo to Page
20Inspect
Ground Master (Key) Switch
Go to Page20
InspectGround/Platform Selector Switch
Go to Page21
InspectIgnition/Emergency Power Switch
Go to Page21
InspectRun Relay
Go to Page22
InspectMagnetic Switch
(Ford only)
Go to Page22
InspectMagnetic Switch
(Kubota only)
OK
OK
OK
OK
Chart 2
Chart 3
Step 1
Step 2
Step 3
Step 4
Step 5
Step 6
Step 1
Go to Page19
InspectStarter Solenoid
OKStep 2
Go to Page23
InspectRun Solenoid(Kubota only)
OKStep 7
OK
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 11 UNO 33/ 41 4X4
Engine will notaccelerate(Ford Only)
Go to Page26
InspectThrottle Circuit Breaker (15 Amp)
Go to Page26
InspectMedium Throttle Relay
Go to Page27
InspectHigh Throttle Relay
Go to Page27
InspectThrottle Governor or Controller
Go to Page28
InspectActuator
OK
OK
OK
OK
Chart 5
Step 1
Step 2
Step 3
Step 4
Step 5
Go to Page29
InspectThrottle Relay
Go to Page30
InspectThrottle Solenoid
OK
Step 6
Step 7
Engine startsthen shuts downafter 30 seconds
Go to Page24
InspectEngine Temperature Gauge
Go to Page24
InspectEngine Oil Pressure Switch
(Ford Only)
OK
Chart 4
Step 1
Step 2
Go to Page25
InspectEngine Oil Pressure Switch
(Kubota Only)
OKStep 3
Engine will notaccelerate
(Kubota Only)
Chart 6
Go to Page29
InspectFuse (10 Amp)
OK
Step 1
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 12 UNO 33/ 41 4X4
Chart 7
Engine overaccelerates(Ford Only)
Go to Page31
Inspect Governor
Go to Page31
InspectActuator
OK
Step 1
Step 2
Engine will notstart from
platform control
Go to Page32
InspectPlatform Control
Circuit Breaker (20 Amp)
Go to Page33
InspectEmergency Stop Switch
Go to Page33
InspectFoot Switch
Go to Page34
InspectPlatform Start Switch
OK
OK
OK
Chart 8
Go to Page32
InspectGround/Platform Selector Switch
OK
Go to Page34
InspectIgnition/Emergency Power Switch
OK
Step 1
Step 2
Step 3
Step 4
Step 5
Step 6
Engine starts whilecranking, then dieswhen key switch is
released
Go to Page35
InspectRun Solenoid
Step 1
Chart 9
Go to Page35
InspectRun Relay
OKStep 2
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 13 UNO 33/ 41 4X4
Engine starter fails tooperate (No Electrical)
InspectPower Cables andBattery Disconnect
Switch
Using a meter set toread voltage, measure
voltage enteringBattery Disconnect SwitchShould read 12-12.7 volts
Battery DisconnectSwitch in Off
Position
If 12-12.7V
Using a meter set toread voltage, turn
Battery Disconnect Switchto On position, measure
voltage coming out ofBattery Disconnect SwitchShould read 12-12.7 volts
Reset BatteryDisconnect Switch
to On Position
If
Repair or replaceBattery Disconnect Switch
and/orBattery Disconnect Switch
wiring
If low or no reading
Go to step 3
If12-12.7V
Then
InspectBatteries
Using a meterset to read
voltage, checkeach battery for12 volts while
under load
Recharge orreplace
battery(s)
Check batteryconnections
If loose
If low or no voltage
Clean allconnections
Tighten allconnections
Ifcorroded
If 12V
Step 1Step 2
Batteries omit hydrogenand oxygen elements thatcan combine explosively.Do not smoke or permitopen flames or sparkswhen checking batteries
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 14 UNO 33/ 41 4X4
Using a meter set to readvoltage, turn BatteryDisconnect Switch to
On position,measure voltage enteringEmergency Stop SwitchShould read 10-12 volts
Step 3
Step 4Inspect
Ground ControlCircuit Breaker
(25 Amp)
Circuit breaker isopen If low or no reading
Check for voltage betweenCircuit Breaker and
Emergency Stop Switchon wire #1A
Should read 12 volts
Reset Circuitbreaker
Then
If
Repair or replaceCircuit Breaker
and/orCircuit Breaker wiring
If low or no reading
Go to step 5
If10-12V
InspectAmmeter
Using a meter set to readvoltage, measure voltage
between1.Battery Disconnect
Switch and Ammeter (+)on wire # 57
2.Ammeter (-) and CircuitBreaker on wire #1A
Should read 12-12.7 volts
If low or no reading
Repair or replaceCircuit Breaker
and/orCircuit Breaker wiringGo to step 4
If12-12.7V
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 15 UNO 33/ 41 4X4
Step 5Step 6
InspectGround Master(Key) Switch
Using a meter set to readvoltage, activate engine
starter and measurevoltage between Battery
post side of GroundMaster Switch and start
side of GroundMaster Switch.
Should read 10-12 volts
FordGo to step 7
KubotaGo to step 8
Repair or replaceGround Master Switch
and/orGround Master Switch
wiring
If10-12V
If low or no reading
InspectEmergency Stop
Switch
Using a meterset to read voltage, pullEmergency Stop Switch
out and measurevoltage between
Emergency Stop Switchand Battery side of
Ground Master(Key) Switch.
Should read 10-12 volts
Emergency StopSwitch is off(pushed in)
If low or no readingPull Emergency
Stop Switch (out)to the On position
If
ReplaceEmergency Stop Switch
and/orEmergency Stop Switch
wiringGo to step 6
If10-12V
Then
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 16 UNO 33/ 41 4X4
Step 7Step 8
InspectGround/PlatformSelector Switch
Set Selector Switch toGround position. Using ameter set to read voltage,
activate starter andmeasure voltage betweenIgnition/Emergency Power
Switch and Ground/Platform Selector SwitchShould read 10-12 volts
Ground/PlatformSelector Switch isin Platform position
Return Ground/Platform SelectorSwitch to Ground
position
Then
If
FordGo to step 9
KubotaGo to step 7
If low or no reading
ReplaceGround/Platform Selector
Switch and/orGround/Platform Selector
Switch wiring
If10-12V
InspectIgnition/Emergency
Power Switch
Using a meter set toread voltage, activate
engine starter andmeasure voltage
betweenGround Master Switch andIgnition/Emergency Power
SwitchShould read 10-12 volts
If low or no reading
ReplaceIgnition/Emergency Power
Switch and/orIgnition/Emergency Power
Switch wiring
FordGo to step 8
KubotaGo to step 10
If10-12V
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 17 UNO 33/ 41 4X4
Step 9Step 10
InspectEngine Starter
Relay
Using a meter set toread voltage, activate
engine starter and measurevoltage from
1. Ford: wire #5B toStarter Relay.Kubota: wire #5A toStarter Relay.
2. wire from Starter Relay to Ground
Should read 10-12 volts
Check groundcontinuity
If10-12V
If low or no reading
ReplaceEngine Starter
Relay
No continuity
ReplaceEngine Starter Relay wiring
Go to step 11
Continuity
Go to step 10
InspectEngine Anti-
Restart Relay(Ford only)
Using a meter set toread voltage, activate
engine starter andmeasure voltage
between Ground ControlSwitch and Anti-Restart
Relay on wire #5C.Should read 10-12 volts
Measure voltage atwire #5B.
Should read 10-12 volts
ReplaceEngine Anti-
Restart Relay
If low or no reading
Replacewiring to
Engine AntiRestart Relay
Check Adjustable Resistorbetween Terminal
164 and 164B. Adjust asneeded for starter to
engage.
If 10-12v
If10-12v
If lowor no
reading
If stilldoesnot
engage
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 18 UNO 33/ 41 4X4
Step 11
InspectStarter Solenoid
Using a meter set toread voltage, activate
engine starter and measurevoltage from
1. Ford: wire #5A toStarter Solenoid
Kubota: wire #165 toStarter Solenoid
2. Starter Solenoid toGround
Should read 10-12 volts
Check groundcontinuity
If10-12V
If low or no reading
ReplaceStarter Solenoid
No continuity
ReplaceStarter Solenoid wiringReturn to step 1
Continuity
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 19 UNO 33/ 41 4X4
Disconnect wire 164Bfrom Alternator. Checkcontinuity between post
and alternator case.
InspectEngine Anti-
Restart Relay
Repair or replaceAlternator
Open field in alternator
No continuity
Locate the adjustableresistor between terminals#164 and #164B, remove
the plastic covering.While activating the starter,slowly slide adjuster untilcranking time is sufficient
for starting engine.Replace the plastic
covering.
Adjust resistor for longercranking time, until enginestarts and alarm shuts off.
(approx. 30 seconds)
Starter disengagesbefore engine starts(Ford only)
Step 1
Continuity
InspectStarter Solenoid
Using a meter set toread voltage, activate
engine starter and measurevoltage from
1. wire #5A to StarterSolenoid
2. Starter Solenoid toGround
Should read 10-12 volts
Check groundcontinuity
If10-12V
If low or no reading
ReplaceStarter Solenoid
No continuity
ReplaceStarter Solenoid wiringReturn to step 1
Continuity
Step 2
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 20 UNO 33/ 41 4X4
Step 1
InspectGround Master(Key) Switch
Using a meter set to readvoltage, activate engine
starter and measurevoltage between Battery
post side of Ground MasterSwitch and ignition side of
Ground Master Switch.Should read 10-12 voltsGo to step 2
Repair or replaceGround Master Switch
and/orGround Master Switch
wiring
If10-12V
No reading
Check Battery
If reading is low
Engine cranks overbut will not start
Step 2Inspect
Ground/PlatformSelector Switch
Set Selector Switch toGround position. Using ameter set to read voltage,
activate starter andmeasure voltage betweenIgnition/Emergency Power
Switch and Ground/Platform Selector SwitchShould read 10-12 volts
Ground/PlatformSelector Switch
is inPlatform position
Return Ground/Platform SelectorSwitch to Ground
position
Then
If
Go to step 3
No reading
ReplaceGround/Platform Selector
Switch and/orGround/Platform Selector
Switch wiring
Check Battery
Ifreading is low
If10-12V
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 21 UNO 33/ 41 4X4
Step 3Step 4
Inspect Ignition/Emergency Power
Switch
Go to step 4
ReplaceIgnition/EmergencyPower Switch and/
orIgnition/Emergency
Power Switchwiring
Check voltage on diodewire between Ignition/
Emergency Power Switchand Ground/Platform
Switch. Replace diode wireif faulty. Measure voltage
entering Run Relay(wire #4A)
Should read 10-12 volts
Using a meter set toread voltage,
measure voltageentering Ignition/
Emergency Power SwitchShould read 10-12 volts
If low or no reading
InspectRun Relay
Using a meter set toread voltage,
measure voltage between Run Relay andMurphy Switch (B Post)
wire #164Should read 10-12 volts
Go to step 5(Ford)
Go to step 6(Kubota)
If10-12V
If low or no reading
ReplaceGround/Platform Selector
Switch and/orGround/Platform Selector
Switch wiring
If10-12V
If lowor no
reading
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 22 UNO 33/ 41 4X4
Step 5Step 6
Inspect Magnetic Switch
( Ford only)
Using a meter set to readvoltage, measure voltage
on wire1. at post NC ofMagnetic Switch
2. on wire 80A betweenMagnetic Switch and
Governor Should read 10-12 volts
ReplaceMagnetic Switch and/or Magnetic Switch wiring
If low or no reading
Inspect Magnetic Switch
( Kubota only)
Using a meter set toread voltage,
measure voltage on wire#8D at post NC of Magnetic Switch
Should read 10-12 volts
ReplaceMagnetic Switch and/or Magnetic Switch wiring
If low or no reading
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 23 UNO 33/ 41 4X4
Step 7
InspectRun Solenoid( Kubota only)
Using a meter set toread voltage,
measure voltage at wire#8D to Run Solenoid
Should read 10-12 voltsNote: Check continuity
to ground on whitejumper wire
ReplaceRun Solenoid
If low or no reading
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 24 UNO 33/ 41 4X4
Step 1Step 2
Engine starts then shutsdown after 30 seconds
InspectEngine Temp.
Gauge
Using a meter set toread ohms,
Check continuity on wirebetween Murphy Switch
(Black wire at S post) andChassis ground
Allow time for Engine tocool down
If resistance is shown
Then
ReplaceMurphy Engine
Temperature Gauge
Return to step 1
InspectEngine Oil
Pressure Switch(Ford only)
Engine oilpressure is due to
inadequate oil level ReplaceEngine Oil Pressure SwitchThen
If oil levelis adequate
Fill to proper levelwith oil
With the engine off,use a meter set to readohms, check continuitybetween wire #3C and
Ground wire at Engine OilPressure SwitchIf
If resistance is shownIf noresistanceis shown
FordGo to step 2
KubotaGo to step 3
If oil levelis adequate
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 25 UNO 33/ 41 4X4
Step 3Return to step 1
InspectEngine Oil
Pressure Switch(Kubota only)
Engine oilpressure is due to
inadequate oil level
ReplaceEngine Oil Pressure Switch
Then
If oil levelis adequate
Fill to proper levelwith oil
Jump wire #3A from EngineOil Pressure Switch toground, start engine
If If engine starts and stay running
If enginedoes not
start
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 26 UNO 33/ 41 4X4
Step 1Step 2
Engine will notaccelerate(Ford only)
InspectThrottle Circuit
Breaker (15 Amp)
Using meter set to readvoltage, measure voltage
Ford: entering eitherMedium Throttle Relay wire
#55A or High ThrottleRelay wire #55B
Deutz: on wire #55Abetween Throttle Relayand Throttle Solenoid
Should read 10-12 volts
Circuit breaker isopen
If low or no reading
Check continuity on wire#55 between ThrottleCircuit Breaker and
Medium Throttle Relay orHigh Throttle Relay
Reset Circuitbreaker
Then
If
Repair or replaceCircuit Breaker and/orCircuit Breaker wiring
Go to step 2(Ford)
Go to step 6(Deutz)
If continuity does not exists
InspectMedium Throttle
Relay(Ford only)
Using a meter set toread voltage,
measure voltageon wire #55A to
Throttle ControllerShould read 10-12 volts
If low or no reading
Check continuity on wirebetween Medium Throttle
Relay and ThrottleController
Repair or replacewiring from
Medium Throttle Relayto Throttle Controller
Then
Go to step 3
Ifcontinuity
doesexists
If10-12V
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 27 UNO 33/ 41 4X4
Step 3Step 4
InspectHigh Throttle
Relay(Ford only)
Using meter set toread voltage,
measure voltageon wire #55B to
Throttle ControllerShould read 10-12 volts
If low or no reading
Check continuity on wirebetween High Throttle
Relay and ThrottleController
Repair or replacewiring from
High Throttle Relayto Throttle Controller
Then
Go to step 4
InspectElectronicGovernor
(Ford only)
Using a meter set toread voltage,
measure voltageon wire #55A and #55B
going into theElectronic Governor
Should read 10-12 volts
If low or no reading
Repair or replacewiring to
Electronic Governor
Go to step 5
If10-12V
If10-12V
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 28 UNO 33/ 41 4X4
Step 5
InspectActuator
Using a meter set toread voltage,
measure voltage,on wire #A1
and #A2 between theElectronic Governor
and SolenoidShould read 10-12 volts
If low or no reading
Repair or replaceElectronicGovernor
If10-12V
Repair or replace Electronic Governor
and/or wiring
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 29 UNO 33/ 41 4X4
InspectThrottle Relay(Kubota only)
Using a meter set to readvoltage, measure voltage
on wire #13D betweenFuse and Throttle RelayShould read 10-12 volts
If 10-12VRepair or replacewiring between
Fuse and ThrottleRelay Activate Ground Control
Switch and measurevoltage on wire #140 to
Throttle SolenoidShould read10-12 volts
If lowor no
reading
Step 1Step 2
Engine will not accelerate(Kubota only)
InspectFuse (10 Amp)
Verify if fuse is blown
Replace Fuse
If blownIf10-12V
Go to step 2
Go to step 3
If Ok
If lowor no
readingReplace Relay
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 30 UNO 33/ 41 4X4
InspectThrottle Solenoid
Using a meter set toread voltage, measure
voltage on wire #14D intoThrottle Solenoid
Should read 10-12 volts
If low or no reading
Repair or replaceThrottle Solenoid and/orThrottle Solenoid wiring
Step 3
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 31 UNO 33/ 41 4X4
Step 1Step 2
Engine over accelerates(Ford only)
InspectElectronicGovernor
Using a meter set toread voltage,
measure voltage,on wire #55A and #55B
going into theElectronic Governor
Should read 10-12 volts
If low or no reading
Repair or replaceFord: wiring to
Electronic Governor
Go to step 2 If10-12V
InspectActuator
Using a meter set toread voltage,
measure voltageon wire #A1
and #A2 between theElectronic Governor
and ActuatorShould read 10-12 volts
If low or no reading
Repair or replaceElectronicGovernor
If10-12V
Repair or replaceElectronic Governor
and/or wiring
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 32 UNO 33/ 41 4X4
Circuit Breaker isopen
Step 1Step 2
Engine will not startfrom platform control
InspectPlatform ControlCircuit Breaker
(20 Amp)
Using a meter set to readvoltage, turn Ground/
Platform Switch to Platformposition, measure voltage
on wire #1 and #2entering Platform Control
Circuit BreakerShould read 10-12 volts
Check for voltage onwire #1B to Emergency
Stop SwitchShould read 10-12 volts
ResetCircuit Breaker
Then
If
Repair or replaceWire #1 and/or #2
Go to step 3
InspectGround/PlatformSelector Switch
Set Selector Switch toPlatform position. Using ameter set to read voltage,
activate starter andmeasure voltage betweenIgnition/Emergency Power
Switch and Ground/Platform Selector SwitchShould read 10-12 volts
Ground/PlatformSelector Switch isin Ground position
Return Ground/Platform SelectorSwitch to Platform
position
Then
If
Go to step 2 If10-12V
If low or no reading
ReplaceGround/Platform Selector
Switch and/orGround/Platform Selector
Switch wiring
ReplaceCircuit Breaker
If lowor no
reading
If lowor no
reading
If 10-12V
If10-12V
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 33 UNO 33/ 41 4X4
Step 3Step 4
InspectFoot Switch and
Wiring
Make sure Foot Switch isnot activated
Deactivate Foot SwitchIfnot
activatedUsing a meter set to readvoltage, measure voltage
on wire #10 going intoFoot Switch and
wire #8 coming outof Foot Switch
Should be 10-12 volts
If activated
InspectEmergency Stop
Switch
Using a meter set to readvoltage, pull Emergency
Stop Switch out andmeasure voltage betweenEmergency Stop Switch
and Battery side ofPlatform Master Switch.Should read 10-12 volts
Emergency StopSwitch is off(pushed in)
If low or no reading
Pull EmergencyStop Switch (out)to the on position
Then
If
ReplaceEmergency Stop Switch
and/orEmergency Stop Switch
wiringGo to step 4 If10-12V
If low or no voltage
Repair or replaceFoot Switchand/or wiring
If10-12VGo to step 5
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 34 UNO 33/ 41 4X4
Step 5
InspectIgnition/Emergency
Power Switch
Using a meter set toread voltage, activate
engine starter andmeasure voltage
on wire #5 betweenPlatform Master Switchand Ignition/Emergency
Power SwitchShould read 10-12 voltsReturn to step 1 If
10-12V
If low or no reading
ReplaceIgnition/Emergency Power
Switch and/orIgnition/Emergency Power
Switch wiring
Step 6
InspectPlatform Start
Switch
Using a meter set toread voltage, activate
Platform Start Switch andmeasure voltage on
wire #5 betweenPlatform Start Switch and
Platform Emergency PowerSwitch
Should read 10-12 voltsGo to step 6 If10-12V
If low or no reading
ReplacePlatform Start Switch
and/orPlatform Start Switch
wiring
SECTION ONEENGINE DIAGNOSTICS
Troubleshooting Guide 35 UNO 33/ 41 4X4
Step 1
Engine starts whilecranking, then dies whenkey switch is released
InspectRun Relay
Using a meter set toread voltage,
measure voltageat Murphy Switch wire
#164, B post ofMurphy Switch
Should read 10-12 volts
If low or no reading
Repair or replaceRun Relay
and/orRun Relay wiring
Step 2
Go to step 2 If10-12V
InspectRun Solenoid
Using a meter set to readvoltage, measure voltageon wire #8D between RunSolenoid Murphy SwitchShould read 10-12 voltsNote: Check continuity
to ground on whitejumper wire
If low or no reading
ReplaceRun Solenoid
and/orRun Solenoid wiring
SECTION TWO:HYDRAULIC DIAGNOSTICS
SECTION TWOHYDRAULICS DIAGNOSTICS
Troubleshooting Guide 39 UNO 33/ 41 4X4
Hydraulic systemfunctions on
emergency poweronly
Go to Page41
InspectMain Hydraulic Pump
Go to Page41
InspectSense Line Dump Valve
Hydraulic pumpstays on stroke
Go to Page42
InspectPump Compensator
Chart 1
Chart 2
OK
Step 1
Step 2
Step 1
Hydraulic functionsare sluggish
Go to Page43
InspectEngine RPM
Go to Page43
InspectPump Pressure
Go to Page44
InspectAccumulator
Go to Page44
InspectFlow from Pump
Chart 3
OK
OK
OK
Step 1
Step 2
Step 3
Step 4
Hydraulic pump willnot build pressure
Go to Page45
InspectPump Compensator Valve
Chart 4
Step 1
Go to Page45
InspectPump Coupling
OKStep 2
SECTION TWOHYDRAULICS DIAGNOSTICS
Troubleshooting Guide 40 UNO 33/ 41 4X4
Hydraulic pumpwill not build
enough pressureGo to Page
46Inspect
Pump Compensator Valve
Go to Page46
InspectSenseline Dump Valve
Chart 5
OK
Step 1
Step 2
Flow fromhydraulic pump
is too lowGo to Page
47
InspectFlow Adjustment on
Main Hydraulic Pump
Chart 6
Step 1
Flow fromhydraulic pump
is too high(kills engine)
Go to Page47
InspectFlow Adjustment on
Main Hydraulic Pump
Chart 7
Step 1
SECTION TWOHYDRAULICS DIAGNOSTICS
Troubleshooting Guide 41 UNO 33/ 41 4X4
Inspect Main Hydraulic
Pump
Remove gaugeand
Go to step 2
CheckMain Hydraulic Pump,Pump Coupling andPump Compensator
Install 1000 psi pressuregauge to hydraulic pumptest plug. Set engine for
idle and measuredifferential/standby
pressure.Should read 250-300 psi
If reading is abnormalReplaceMain Hydraulic
Pump and/or PumpCoupling and/or
PumpCompensator
Ifmal-
functioning
Hydraulic system functionson emergency power only
Step 1Step 2
Inspect Sense Line Dump
Valve
Check seals onSense Line Dump
Valve
If10-12V
Repair or replaceSense Line Dump Valve
and/or wiring
Using a meter set to readvoltage, activate Ground
Control Switch andmeasure voltage
1.on wire #28B betweenTerminal Stripin Junction Box andSense Line Dump Valve
2.on wire # 28B atSense Line Dump Valve
Should read 10-12 volts
If low or no reading
Repair or replaceSense Line Dump
Valve
If bad
Ok
Go to step 3
If250-300 psi
SECTION TWOHYDRAULICS DIAGNOSTICS
Troubleshooting Guide 42 UNO 33/ 41 4X4
Hydraulic pumpstays on stroke
Step 1
InspectPump
CompensatorValve
Check seals onSense Line Dump
Valve
Repair or replacePump Compensator
Remove hose fromcompensator. Recheck
pressure on Pump.
If stays on stroke
Repair or replaceSense Line Dump Valve
Ifgoesoff
stroke
If bad
SECTION TWOHYDRAULICS DIAGNOSTICS
Troubleshooting Guide 43 UNO 33/ 41 4X4
Step 1
Step 2
Hydraulic functionsare sluggish
InspectEngine RPM
Adjust Throttle Actuatoror Solenoid
Use a Tachometer tomeasure Engine RPM
Should read:Ford - 1050 RPM at Low 2100 RPM at Mid 2800 RPM at HighKubota -1500-1800 RPM at
Low 3200 RPM at High
If not
Go to step 2 If correctRPM
InspectPump Pressure
AdjustPump Compensator
Install 1000 psipressure gauge at
Test Port.Set engine for idle
and measure standbypressure.
Should read 250-300 psi
If low or no reading
Remove gaugeand
Go to step 3
If300 psi
SECTION TWOHYDRAULICS DIAGNOSTICS
Troubleshooting Guide 44 UNO 33/ 41 4X4
Step 3
Step 4
InspectAccumulator
RechargeAccumulator
Measure the chargeon the Accumulator
Should be 750 to 800 psi
If low or no reading
Go to step 4
If750 to 800 psi
InspectFlow from Pump
AdjustFlow Ajustment
With chassis raised(all wheels off the ground)and adequately supported,
1.Install a Flowmeter onthe discharge side ofpump.
2.Install a 1000 psipressure gauge at TestPort on Accumulator.Start engine and turnThrottle Switch to high.Activate drive functionfull on.
Flowmeter should read12 to 14 gpm and
pressure gauge shouldread 300 psi
If low or no reading
Remove gaugesand
Return to step 1
If12 to
14 gpmand
300 psi
SECTION TWOHYDRAULICS DIAGNOSTICS
Troubleshooting Guide 45 UNO 33/ 41 4X4
Step 1Step 2
Hydraulic pump willnot build pressure
InspectPump
CompensatorValve
Go to step 2
Remove hoses fromSense Line Dump Valveto Compensator Valve
and reattach toPressure Line. Using a
5000 psi pressure gaugecheck pressure.
Should read 2400 psiIf noreading
Remove gauge andcheck seals on
Sense Line Dump Valve
Repair or replaceSense Line Dump Valve
If bad
InspectPump Coupling
Repair or replacePump Coupling
RemoveMain Hydraulic Pump
visually checkPump Coupling
If bad
Ok
Repair or replaceCompensator
and/orMain Hydraulic Pump
If 2800 psi
SECTION TWOHYDRAULICS DIAGNOSTICS
Troubleshooting Guide 46 UNO 33/ 41 4X4
Step 1Step 2
Hydraulic pump will notbuild enough pressure
Inspect Sense Line Dump
Valve
Check seals onSense Line Dump
Valve
If10-12V
Repair or replaceSense Line Dump Valve
wiring
Using meter set to readvoltage, activate Ground
Control Switch andmeasure voltage
1. On wire #28B betweenTerminal Strip inJunction Box andSense Line Dump Valve
2. On wire # 28B atSense Line DumpValve
Should read 10-12 volts
If low or no reading
Repair or replaceSense Line Dump
Valve
If bad
InspectPump
CompensatorValve
Go to step 2
Remove hoses fromSense Line Dump Valveto Compensator Valve
and reattach toPressure Line. Using a
5000 psi pressure gaugecheck pressure.
Should read 2800 psi
If noreading
Remove gauge andcheck seals on
Sense Line Dump Valve
Repair or replaceSense Line Dump Valve
If bad
If 2800 psi
If lowreadingAdjust
CompensatorValve
SECTION TWOHYDRAULICS DIAGNOSTICS
Troubleshooting Guide 47 UNO 33/ 41 4X4
Step 1Step 1
Flow from hydraulicpump is too low
Flow fromhydraulic pumpis too high(kills engine)
InspectFlow Adjustment
on Main HydraulicPump
Visually check FlowAdjustment Screw on Main
Hydraulic PumpScrew should extendbetween 3/4" and 7/8"
from face of pump
ResetFlow Adjustment on Main
Hydraulic Pump
InspectFlow Adjustment
on Main HydraulicPump
Visually check FlowAdjustment Screw on Main
Hydraulic PumpScrew should extendbetween 3/4" and 7/8"
from face of pump
ResetFlow Adjustment on Main
Hydraulic Pump
SECTION THREE:STEERING SYSTEM DIAGNOSTICS
SECTION THREESTEERING SYSTEM DIAGNOSTICS
Troubleshooting Guide 51 UNO 33/ 41 4X4
Machine will notsteer
Go to Page52
InspectSteer Switch
Go to Page52
Inspect3 Way Valve
Go to Page53
InspectSteer Control Valve
Go to Page54
InspectCenter Post
Go to Page54
InspectTow Package Float Valve
OK
OK
OK
OK
Chart 1
Step 1
Step 2
Step 4
Step 5
Step 6
Go to Page53
InspectBoom Speed Dial
OKStep 3
SECTION THREESTEERING SYSTEM DIAGNOSTICS
Troubleshooting Guide 52 UNO 33/ 41 4X4
Machine will not steer
Step 1Step 2
Note:At this point the manualoverride may also beuse to isolatethe solenoid, howeveruse caution as themachine will be moving.
InspectSteer Switch
Go to step 2 If10-12V
ReplaceSteer Switch
and/orSteer Switch wiring
Using a meter set to readvoltage, activate Steer
Right Switch and measurevoltage on wire #20
between Steer Switch andSteer Control Valve.
Activate Steer Left Switchand measure voltage on
wire #19.Should read 10-12 volts
If low or no reading
InspectBlocking Valve
Go to step 3Repair or replace
Blocking Valve Cartridge
Visually check BlockingValve Cartridge for
binding
Should normally be closed.
If stuckIf
Ok
Using a meter set to readvoltage, activate Steerfunction and measurevoltage on wire #160
between Steer Switch and3-Way Valve
Should read 10-12 volts
If 10-12V
Repair or replaceSwitch and/or
wiring
If lowor no
reading
SECTION THREESTEERING SYSTEM DIAGNOSTICS
Troubleshooting Guide 53 UNO 33/ 41 4X4
Step 3Step 4
Note:At this point the manualoverride may also beuse to isolatethe solenoid, howeveruse caution as themachine will be moving.
InspectBoom Speed Dial
Turn to full speed
Remove wire #16B fromBy-Pass Coil on Main
Hydraulic Valve and retryfunction
Visually checkSpeed Dial for full speed
If full speed
If notfull speed
Remove By-Pass Valvefrom Main Valve and
inspect. Valve is normallyclosed
If no change
If steerok
ReplaceSpeed Dial in
Platform
Activate Manual Overrideon Valve while activating
Steer function
If Ok
Replace Valve If stuck
Go to step 4 If Ok
Go to step 5
If function does not operate
InspectSteer Control
Valve
Repair or replaceSteer Control
Valve or Solenoid Go to Step 5
ActivatingManual Overrides and
check pressureShould be 2400 psi
If lower than 2400 psi
If approx.2400 psi
SECTION THREESTEERING SYSTEM DIAGNOSTICS
Troubleshooting Guide 54 UNO 33/ 41 4X4
Step 5
InspectCenter Post
Repair or replaceSteer Cylinder
Note: Machineswith optionalTow Packagego to step 6
Ifreading
isnormal
Repair or replaceCenter Post
Remove hoses leading to Steer Cylinder Plug
hoses andcap the Steer Cylinder.
While activatingsteering function,
check for 2400 psi atthe pump pressure Test
Port
If reading is abnormal
InspectTow Package Float
Valve
Refer to Chapter 12Accessories Diagnostics
During activation ofsteering function themachine will be moving.
Step 6
SECTION FOUR:DRIVE SYSTEM DIAGNOSTICS
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 57 UNO 33/ 41 4X4
Drive system is notoperational with
controller in eitherdirection
Go to Page61
InspectFoot Switch
Go to Page61
InspectDrive Fuse
Go to Page62
InspectController Circuit Board and S1
Micro Switch Wiring
Go to Page62
InspectS1 Micro-Switch (in Controller)
Go to Page63
InspectController Circuit Board
Go to Page63
InspectPotentiometer
Go to Page64
InspectS2 Micro-Switch (in Controller)
Go to Page64
InspectDrive Solenoid
Go to Page65
InspectDrive Control Valve
Go to Page65
InspectCenter Post
Go to Page66
InspectDual Counterbalance Valve
OK
OK
OK
OK
OK
OK
OK
OK
OK
OK
Chart 1
Step 1
Step 2
Step 3
Step 4
Step 5
Step 6
Step 7
Step 8
Step 9
Step 10
Step 11
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 58 UNO 33/ 41 4X4
No forward drive(reverse ok)
Go to Page67
InspectS2 Micro-Switch
(in Drive Controller)
Go to Page67
InspectDrive Controller Circuit Board
Go to Page68
InspectSolenoid
(Drive Forward on Control Valve)
Go to Page68
InspectDual Counterbalance Cartridge
No reverse drive(forward ok)
Go to Page69
InspectS2 Micro-Switch
(in Drive Controller)
Go to Page69
InspectDrive Controller Circuit Board
Go to Page70
InspectSolenoid Valve
(Drive reverse on Control Valve)
Go to Page70
InspectDual Counterbalance Cartridge
OK
OK
OK
OK
OK
OK
Chart 2
Chart 3
Step 1
Step 2
Step 3
Step 4
Step 1
Step 2
Step 3
Step 4
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 59 UNO 33/ 41 4X4
Inspect3-Way Cartridge Valves in
Transmission Valve
Drive high rangenot operating
(mid speed ok)Go to Page
71Inspect
Drive Range Switch
Go to Page71
InspectBoom Position and/or
Boom Limit Switch
Go to Page72
Inspect2 Wheel Motor Shift Valve
Go to Page72
OK
OK
OK
Chart 4
Step 1
Step 2
Step 3
Step 4
InspectLeft and Right Motor Shift Valves
Drive mid rangenot operating
(low speed ok)Go to Page
73Inspect
Drive Range Switch
Go to Page73
InspectBoom Limit Switch
Go to Page74
InspectSteer Limit Switches
Go to Page74
OK
OK
OK
Chart 5
Step 1
Step 2
Step 3
Step 4
InspectPower to R Terminal on Controller
Go to Page75
OKStep %
Wheels on one siderotate faster than on
other sideGo to Page
76Inspect
Drive Range Switch
Go to Page76
InspectBoom Limit Switch
OK
Chart 6
Step 1
Step 2
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 60 UNO 33/ 41 4X4
One wheel rotatesslower than others
Go to Page78
Inspect3-Way Cartridge Valves
Go to Page78
InspectFlow Divider (spool type)
OK
Chart 7
Step 1
Step 2
Brakes will notrelease
Go to Page80
InspectBrake Pressure
Chart 8
Step 1
Go to Page79
InspectWheel Motors
OKStep 2
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 61 UNO 33/ 41 4X4
InspectFoot switch Using a meter set to
read voltage, activateFoot Switch andmeasure voltage
1. on wire #9 betweenFoot Switch and DriveFuse
2. at 3 amp Drive FuseShould read 10-12 volts
If low or no voltage
ReplaceFoot Switch and/orFoot Switch wiring
Go to step 2 If10-12V
Drive system is non-operationalwith controller in either direction
Step 1Step 2
InspectDrive Fuse (3 amp)
Using a meter set toread voltage, activate
Foot Switch andmeasure voltage
1. on wire # betweenDrive Fuse andDrive Controller
2. at positive (+) post ofDrive controller
Should read 10-12 volts
If low or no voltage
ReplaceFoot Switch and/orFoot Switch wiring
Go to step 3 If10-12V
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 62 UNO 33/ 41 4X4
Step 3Step 4
InspectController Circuit
Board and S1Micro-Switch
Wiring
Using a meter set toread voltage, activate
Foot Switch andmeasure voltage
1. on red wire fromCircuit Board toS1 Micro-Switch
2. at red wire ofS1 Micro-Switch
Should read 10-12 volts
If low or no voltage
ReplaceCircuit Board
and/orS1 Micro-Switch wiring
Go to step 4 If10-12V
InspectS1 Micro-Switch
(in Controller)
Using a meter set toread voltage, step on
Foot Switch andactivate Controller,measure voltage
1. on black wire betweenS1 Micro-Switch andController Circuit Board
2. at point where blackwire from S1 Switchenters Controller CircuitBoard
Should read 10-12 volts
ReplaceS1 Micro-Switch
(in Controller)and/or
S1 Micro-Switchwiring
Go to step 5
Move controller handle ineither direction andobserve red LED on
Circuit Board Controller
If not lit
If lit
If lowor no
voltage
Go to step 5 If10-12V
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 63 UNO 33/ 41 4X4
Step 5Step 6
Using a meter set toread voltage, step on
Foot Switch andactivate Controller,measure voltage
1. on green wire toPotentiometer fromController Circuit Board
2. on wire betweenController Circuit Board
and PotentiometerShould read 10-12 volts
If low or no voltage
ReplaceController Circuit Board
and/orController Circuit Board
wiring
Go to step 6 If10-12V
InspectController Circuit
Board
InspectPotentiometer
Using a meter set to ohms,measure reading across1. green wire and purple
wire between ControllerCircuit Board andPotentiometer
2. green wire and orangewire between ControllerCircuit Board andPotentiometerReading should vary
according to Controllermovement
If no reading
Check continuity on wirebetween Controller CircuitBoard and Potentiometer
Go to step 7
continuity
ReplacePotentiometer
and/orPotentiometer
wiring
Nocontinuity
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 64 UNO 33/ 41 4X4
Step 7Step 8
InspectS2 Micro-Switch
(in Controller)
Using a meter set toread voltage, step on
Foot Switch and activateController, perform the
following:1. While activating
controller in forwardmode measureproportional voltage atController Circuit Boardwhere white wire entersfrom S2 Micro-Switch
2. While activatingController in reversemode measureproportional voltage atController Circuit Boardwhere blue wire entersfrom S2 Micro-Switch
Reading should varyaccording to amount of
reverse movement
Check continuityon blue wire and
on white wirebetween ControllerCircuit Board andS2 Micro-Switch
If noreading
ReplaceS2 Micro-Switch
and/orS2 Micro-Switch
wiring
No Continuity
Go to step 8
Continuity
Push Manual Overridewhile activating variouscontroller functions and
check operation.
If functions are abnormal or erratic
Replace Drive Section Control Valve
Go to step 9
InspectDrive Solenoid
Machine function will bemoving when manualoverride is activated.
Iffunctions
arenormal
If Ok
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 65 UNO 33/ 41 4X4
Step 9Step 10
Remove hoses from drivesection of Control Valve.Plug the hoses and capvalve. Install a 5000 psi
pressure gauge toPump Test Port.
While activating drivecontrol function, check
pressure.Should read 2400 psi
(while activating function)
If functions are abnormal or erratic
ReplaceValves on Drive Section
of Control Valve
Remove gaugeand
Go to step 10
InspectDrive Control
Valve
InspectCenter Post
Remove hoses at V1 andV2 ports of Dual
Counterbalance Valve.Plug hoses and cap valve.Install a 5000 psi pressure
test gauge toPump Test Port
While activating drivecontrol function, check
pressure.Should read 2400 psi
(while activating function)
If pressures are abnormal or erratic
Repair or replaceCenter Post
Remove gaugeand
Go to step 11
If functionsare normal
If pressuresare normal
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 66 UNO 33/ 41 4X4
Step 11
Replace DualCounterbalance Valve, and
retry function
If still no function
Return to step 1
InspectDual
CounterbalanceValve
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 67 UNO 33/ 41 4X4
Step 1Step 2
No forward drive(Reverse Ok)
InspectDrive Controller
Circuit Board
Using a meter set toread voltage, activate drive
function and measureproportional voltage at
Terminal A ofCircuit Board.
Reading should varyaccording to controller
movement.
If no or erratic reading
ReplaceDrive Controller Circuit
Board
Go to step 3 Ifnormal
InspectS2 Micro-Switch
(in DriveController)
Go to step 2 Ifnormal
Check continuity on bluewire between S2 Micro-Switch and Controller
Circuit Board
Using a meter set toread voltage, activatefunction and measureproportional voltage atController Circuit Boardat point where blue wire
from S2 Micro-Switchenters.
Reading should varyaccording to controller
movement.
If low or no readingReplaceS2 Micro-Switch
and/orS2 Micro-Switch
wiringno continuity
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 68 UNO 33/ 41 4X4
Step 3Step 4
Replace theDual Counterbalance Valve
Cartridge tested
InspectDual
CounterbalanceValve Cartridge
Using a 5000 psi pressuretest gauge activate drive
function and check systempressure at hose entering
port C2 on CounterbalanceValve
Should read 0-500 psi
If pressure reading is high
ReplaceDrive Forward Solenoid
Valve and/orDrive Forward Solenoid
Valve wiring
InspectSolenoid Valve(Drive forward
on Control Valve)
Go to step 4
Try manual override
Using a meter set to readvoltage. While activating
forward function, measureproportional voltage at wire
#17 on Drive section ofControl Valve.
Reading should varyaccording to controller
movement.If no reading
Override allows operation
Overridedoes not
allowoperation
Machine function will bemoving when manualoverride is activated.
Return to step 1 If0-500 psi
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 69 UNO 33/ 41 4X4
Step 1Step 2
No reverse drive(Forward Ok)
InspectDrive Controller
Circuit Board
Using a meter set toread voltage, activate
reverse functionand measure
proportional voltage atTerminal B of
Controller Circuit BoardReading should vary
according to controllermovement
If no or erratic reading
ReplaceDrive Controller Circuit
Board
Go to step 3 Ifnormal
InspectS2 Micro-Switch
(in DriveController)
Go to step 2 Ifnormal
Check continuity on whitewire between S2 Micro-Switch and Controller
Circuit Board
Using a meter set toread voltage, activatereverse function andmeasure proportionalvoltage at ControllerCircuit Board at pointwhere white wire from
S2 Micro-Switch enters.Reading should vary
according to controllermovement.
If low or no readingReplace
S2 Micro-Switchand/or
S2 Micro-Switchwiring
No continuity
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 70 UNO 33/ 41 4X4
Step 3Step 4
ReplaceDrive Reverse
Solenoid Valve and/orDrive Reverse Solenoid
Valve wiring
InspectSolenoid Valve
(Drive reverse onControl Valve)
Go to step 4
Try manual override
Using a meter set to readvoltage. While activating
reverse function,measure proportionalvoltage at wire #18 on
Drive section ofControl Valve.
Reading should varyaccording to controller
movement.
If no reading
Override allows operationOverridedoes not
allowoperation
Machine function will bemoving when manualoverride is activated.
Replace theDual Counterbalance Valve
Cartridge tested
InspectDual
CounterbalanceValve Cartridge
Using a 5000 psi pressuretest gauge activate drive
function and check systempressure at hose entering
port C1 on CounterbalanceValve
Should read 0-500 psi
If pressure reading is high
Return to step 1 If0-500 psi
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 71 UNO 33/ 41 4X4
Position Booms to fullydown position. Adjust BoomRetract/Down Limit Switch
InspectBoom Position
and/orBoom Limit Switch
Booms are not positionedfor High Range speed
operationsBoom Limit Switch are
not Adjusted
Step 1Step 2
Drive high rangenot operating(mid speed ok)
InspectDrive Range
Switch
Go to step 2If lowor no
reading
Using a meter set to readvoltage, measure voltage
on wire #70B going into theR Terminal of Drive Controller
Should read 10-12 volts
If low or no reading
ReplaceDrive Range Switch
and/or wiring
still not operating
Check for 10-12 volts onwire #70 at Boom Up Limit
Switch
Measure voltage on wire#170 coming out of the
Drive Range Switch.Should read 10-12 volts
If 10-12V
Repair or replaceBoom Up LimitSwitch and/or
wiringIf 10-12V
Repair or replaceWiring to R Terminal of
Drive Controller
Note: High speed onlyworks in forward direction
Go to step 3
Check Hi Speed Micro-Switch on controller.
should trip at 80% forwardmovement.
Measure voltagefrom Micro Switch
to Drive RangeSwitch.
should read 10-12volts when driving
full forward
If Ok
If 10-12V
If 10-12V
Replace Switch
Adjust Micro-Switch If not
If low or no reading
If novoltage
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 72 UNO 33/ 41 4X4
Step 3Step 4
Inspect2 Wheel Motor
Shift Valve
Remove valve andcheck for stuckValve or blown
O'Rings
Using a 5000 psi pressuregauge, measure pressureon hose between 2 Wheel
Motor Shift Valve andCenter Post.
Should read 0 psi
If no reading
Repair or replaceWiring to Shift Coil
Go to step 4
Using meter set toread voltage, measure
voltage at 2 Wheel MotorShift Coil wire #170 .
Should read 10-12 volts
If10-12V
If Ok
Ifpressureis high
Repair or replace3-Way Cartridge Valve in
Transmission Valve
Inspect3-Way Cartridge
Valve inTransmission
Valve
Go to step 5
Verify that Valves areshifting by Removing valve
and checking formovement.
If not moving
If bad
Repair or replaceas needed
If Ok
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 73 UNO 33/ 41 4X4
Step 1
Step 2
Drive mid range notoperating (low speed ok)
InspectDrive Range
Switch
Using a meter set to readvoltage, measure voltage
on wire #11 on DriveRange Switch
Should read 0 voltswith switch in Mid Speed
If voltage
ReplaceSwitch with
Part # 302-0017 only
Go to step 2 If 0V
InspectBoom Limit Switch
With booms down, use ameter set to read voltage,measure voltage on wire#34 of Boom Limit Switch
Should read 0 voltsGo to step 3 If 0V
Repair, replace or adjustBoom Limit Switch
If voltage
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 74 UNO 33/ 41 4X4
Step 3Step 4
InspectSteer LimitSwitches
With tires straight, checkswitches on steering toverify if activated or not
activatedSwitches should not be
activated
If not activated
Using a meter set to readvoltage, measure voltageon wire 34L on left Motor
Shift Valve and on 34R onright Motor Shift Valve
Should read 0 volts
Readjust Switches Ifactivated
InspectLeft and Right
Motor Shift Valves
Install a 5000 psi pressuregauge in line with Port B1(for right) or B2 (for left) of
Drive Shift Valve.Should read same pressure
as on compensator ofPump or Drive Pressure
Go to step 5 If Ok
Repair, replace Motor Shift Valves
If low or no pressure
If voltage
Repair or replaceSteer Switches
Go to step 4 Ifactivated
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 75 UNO 33/ 41 4X4
Step 5
Return to step 1
InspectPower to RTerminal
Adjust High Speed Trim Poton controller to get
3 mph = 100 ft in 22 sec.
With Boom retracted andlowered, use a meter setto read voltage, measurevoltage at the R Terminal
of Drive ControllerShould read 10-12 volts
If no reading If10-12V
Check connectionon Boom Wirebetween BoomSwitches and
Platform
Iflow
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 76 UNO 33/ 41 4X4
Step 1Step 2
Wheels on one side rotatefaster than other side
Note:In mid and high only.
InspectSteer LimitSwitches
With tires straight, checkswitches on steering toverify if activated or not
activatedSwitches should not be
activated
If not activated
Using a meter set to readvoltage, measure voltageon wire 34L on left Motor
Shift Valve and on 34R onright Motor Shift Valve
Should read 0 volts
Readjust Switches Ifactivated
If voltage
Repair or replaceSteer Switches
Go to step 2 Ifactivated
InspectLeft and Right
Motor Shift Valves
Install a 5000 psi pressuregauge in line with Port B1(for right) or B2 (for left) of
Drive Shift Valve.Should read same pressure
as on compensator ofPump or Drive Pressure
Repair, replace Motor Shift Valves
If low or no pressure
Go to step 3 If Ok
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 77 UNO 33/ 41 4X4
Step 3
InspectWheel Motor
Remove Case Drain Hosefrom slow motor, install
flowmeter in line.Drive machine and read
flowmeter.Should read less than
.5 gpm
If more than .5 gpm
ReplaceMotor
Go to Chart 8If lessthan
.5 gpm
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 78 UNO 33/ 41 4X4
Step 1Step 2
One wheel rotates slowerthan others
Note:In mid range forward only.
Inspect3-Way Cartridge
Valves
If Front Left Wheel or RearRight Wheel
Remove 3-way CartridgeValves from Right
Transmission Valve.Inspect for shifting or blown
o'rings
If Front Right Wheel orRear Left Wheel
Remove 3-way CartridgeValves from Left
Transmission Valve.Inspect for shifting or blown
o'rings
If bad
Repair or replaceas needed
Go to step 2 If Ok
Inspectflow Divider(Spool type)
If Front Left Wheel orRear Right Wheel, remove
Flow Divider from rightTransmission Valve.
Inspect for broken springsor scratches on Valve
If Front Right Wheel orRear Left Wheel, remove
Flow Divider from leftTransmission Valve.
Inspect for broken springsor scratches on Valve
Repair or replaceas needed
If bad
Go to step 3 If Ok
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 79 UNO 33/ 41 4X4
Step 3
InspectWheel Motor
Remove Case Drain Hosefrom slow motor, install
flowmeter in line.Drive machine and read
flowmeter.Should read less than
.5 gpm
If more than .5 gpm
ReplaceMotor
Go to Chart 8If lessthan
.5 gpm
SECTION FOURDRIVE SYSTEM DIAGNOSTICS
Troubleshooting Guide 80 UNO 33/ 41 4X4
Brakes will notrelease
Step 1
InspectBrake Pressure
1. Install a 5000 psipressure gauge inBrake Port Drive Motor
2. Take pressure readingat Pump Compensator
Readings should besimilar
Repair or replaceBrake Orifice located in
Bulk Head Fitting going toBrake
SECTION FIVE:EMERGENCY POWER SYSTEM DIAGNOSTICS
SECTION FIVEEMERGENCY POWER SYSTEM DIAGNOSTICS
Troubleshooting Guide 83 UNO 33/ 41 4X4
Emergency pumpmotor non-operational
Go to Page84
InspectEmergency Power Switch
Go to Page85
InspectEmergency Power Solenoid
and Wiring
Go to Page85
InspectEmergency Power Unit
No functions whenon emergency
power
Go to Page86
InspectEmergency Power Pump
OK
OK
Chart 1
Chart 2
Step 2
Step 3
Step 4
Step 2
Go to Page84
InspectBattery and Cable Connections
OK
Step 1
Go to Page86
InspectBattery and Cable Connections
OK
Step 1
SECTION FIVEEMERGENCY POWER SYSTEM DIAGNOSTICS
Troubleshooting Guide 84 UNO 33/ 41 4X4
Repair or ReplaceEmergency PowerSwitch Terminalwiring (wire #6)
and/orEmergency Power
Solenoid wiring(wire #6A)
and/orEmergency Power
Switch
InspectEmergency Power
Switch
Go to step 3
Check continuity1. on wire #6 between
Emergency PowerSwitch and TerminalStrip in Control Box
2. between wire #6 ofTerminal Strip inJunction Box and wire#6A at EmergencyPower Solenoid
Using a meter set toread voltage, activate
Emergency Power andmeasure voltage
1. on wire #6 ofEmergency PowerSwitch
2. at Emergency PowerSolenoidShould be 10-12 volts
If no reading
If10-12V
Step 1
Step 2
Emergencypump motornon-operational
No continuity
InspectBatteries
Using a meterset to read
voltage, checkeach battery for12 volts while
under load
Recharge orreplace
battery(s)
Check batteryconnections
If loose
If low or no voltage
Clean allconnections
Tighten allconnections
Ifcorroded
If 12V
Batteries omit hydrogenand oxygen elements thatcan combine explosively.Do not smoke or permitopen flames or sparkswhen checking batteries
If Ok
Go to step 2
SECTION FIVEEMERGENCY POWER SYSTEM DIAGNOSTICS
Troubleshooting Guide 85 UNO 33/ 41 4X4
Step 3
Repair or ReplaceEmergency Pump Motor
InspectEmergency Power
Unit
If previous checks havebeen performed and found
to be normal, checkEmergency Pump Motor
for internal groundingcondition
Repair or ReplaceWiring from BatteryDisconnect Switch
to EmergencyPower Solenoid
and/or Emergency PowerUnit wiring and/orEmergency Power
Solenoid
InspectEmergency Power
Solenoidand Wiring
Go to step 4
Check continuity1. on wire between
Battery DisconnectSwitch and EmergencyPower Solenoid
2. on wire betweenEmergency PowerSolenoid and PumpMotor
Using a meter set to readvoltage, measure voltage1. at Emergency Power
Solenoid and fromBattery DisconnectSwitch
2. activate EmergencyPower Switch andmeasure voltage atEmergency PumpMotor
Should be 10-12 volts
If no reading
If10-12V
Step 4
Nocontinuity
SECTION FIVEEMERGENCY POWER SYSTEM DIAGNOSTICS
Troubleshooting Guide 86 UNO 33/ 41 4X4
Step 1
No functions when onemergency power
Step 2
InspectBatteries
Using a meterset to read
voltage, checkeach battery for12 volts while
under load
Recharge orreplace
battery(s)
Check batteryconnections
If loose
If low or no voltage
Clean allconnections
Tighten allconnections
Ifcorroded
If 12V
Batteries omit hydrogenand oxygen elements thatcan combine explosively.Do not smoke or permitopen flames or sparkswhen checking batteries
Repair or ReplaceEmergency Power Pump
Unit
InspectEmergency Power
Pump
Attach 5000 psi pressuregauge to discharge
side of Emergency PowerPump, activate
Emergency Power Pumpand Ground Control Switch
or Foot Switch.Should read 1750 psi.
If reading is abnormal or erratic
Remove gaugeand
Go to step 3
IfOk
If Ok
Go to step 2
SECTION SIX:SWING SYSTEM DIAGNOSTICS
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 89 UNO 33/ 41 4X4
No response fromswing when
platform controlsare activated
(GroundControls Ok)
Go to Page93
InspectFoot Switch
Go to Page93
InspectPlatform Boom Speed Dial
Go to Page94
InspectSwing Switch
Go to Page94
InspectSwing Valve
OK
OK
OK
Chart 2
Step 1
Step 2
Step 3
Step 4
Swings only inone direction
Go to Page92
InspectSwing Control Signal Wire
Go to Page92
InspectSwing Control Valve
OK
Chart 1
Step 1
Step 2
No response fromswing when groundcontrol is activated
(PlatformControl Ok)
Go to Page96
InspectGround Control Switch
and Wiring
Go to Page96
InspectGround Control Boom Speed Dial
OK
Chart 3
Step 1
Step 2
Go to Page95
InspectSwing Motor and Gear Box
OKStep 5
Go to Page97
InspectSwing Switch
OKStep 3
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 90 UNO 33/ 41 4X4
Swings faster oneway than other
Go to Page100
InspectCrossover Relief Valve
Go to Page100
InspectSolenoid
OK
Chart 5
Step 1
Step 2
Swings erraticallyin either direction
Go to Page98
ActivateManual Override
Go to Page98
InspectSolenoid
Go to Page99
InspectSwing Switch
Go to Page99
InspectSwing Brake
OK
OK
OK
Chart 4
Step 1
Step 2
Step 3
Step 4
Swing Brakewill not hold
Go to Page101
InspectSwing Brake
Chart 6
Step 1
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 91 UNO 33/ 41 4X4
Swings too slow Go to Page102
ActivateManual Override
Go to Page102
InspectSolenoid
Go to Page103
InspectSwing Valve
Go to Page103
InspectSwing Brake Release
OK
OK
OK
Chart 7
Step 1
Step 2
Step 3
Step 4
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 92 UNO 33/ 41 4X4
Step 1Step 2
Repair or ReplaceSwing Control Valve
wiring
Inspect Swing Control
Signal Wire
Check continuity on1. wire #23 between
Terminal Strip in thePlatform Box andSwing Control Valve
2. wire #24 betweenTerminal Strip in thePlatform Box andSwing Control Valve
Using meter set to readvoltage, perform the
following:1. while activating
platform in ccwdirection, measurevoltage on wire #23 atthe Terminal Strip inthePlatform Box
2. while activatingplatform in cw direction,measure voltage onwire #24 at theTerminal Strip atPlatform BoxShould be 10-12 volts
Go to step 2 If10-12 V
No continuity
Swings only inone direction
If no reading
Repair or ReplaceSwing Control Valve
Solenoid
InspectSwing Control
Valve
Manually operateSwing Control Valve
If functioning properlyIf functioningimproperly
Repair or ReplaceSwing Control
Valve
When the turn tablerotates clockwise (cw) itwill be moving toward you.Make sure you have roomto step backward.
Machine function will bemoving when manualoverride is activated.
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 93 UNO 33/ 41 4X4
Step 2
No response from swing whenplatform controls are activated(Ground Controls Ok)
Repair or ReplaceFoot Switch and/orFoot Switch wiring
InspectFoot Switch
Go to step 2
Check continuity on wire#9 between Foot Switch
and Swing Circuit Breaker
Using a meter set to readvoltage, while stepping onthe Foot Switch, measure
voltage on wire # 9 atSwing Switch
Should read 10-12 volts
If no reading
No continuity
If10-12V
Step 1
InspectPlatform Boom
Speed Dial
Turn to full speed Remove wire #16 from By-Pass Coil on Main
Hydraulic Valve and retryfunction
Visually checkSpeed Dial for full speed
If full speedIf notfull speed
Remove By-Pass Valvefrom Main Valve and
inspect.Valve is normally closed
If no change
ReplaceSpeed Dial in
Platform
If Ok
Replace Valve If stuck
Go to step 3
If swingok
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 94 UNO 33/ 41 4X4
Step 3Step 4
ReplaceSwing Section Control
Valve
InspectSwing Valve
Remove hoses fromSwing Drive Motor.Plug hoses and cap
motor. While activatingswing function, check
pressure atPump Compensator
Pressure should read1100 psi
If reading is low or erratic
Go to step 5 If1100 psi
InspectSwing Switch
Using a meter set toread voltage, while
activating function, checkvoltage on Swing Switch to
Junction Box(wire #23 when swing
is moving in acounterclockwise direction,
wire #24 when swingis moving in a
clockwise direction)Should be 10-12 volts
If no reading
Repair or ReplaceSwing Switch
and/orSwing Switch wiring
Go to step 2 If10-12V
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 95 UNO 33/ 41 4X4
Step 5
ReplaceSwing Motor and/or
Gear Box
InspectSwing Motor and
Gear Box
If previous steps havebeen made and Swing
Valve checks ok,check pressure.
If lowReturn to step 1
If2500 psi
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 96 UNO 33/ 41 4X4
Repair or ReplaceGround Control Switch
and/orGround Control Switch
wiring
InspectGround Control
Switch and Wiring
Go to step 2
Using a meter set to readvoltage, activate swing
function, measure voltagefrom Ground ControlSwitch to Ground Swing
Switch Should be 10-12 volts
If no reading
If10-12V
No response from swing whenground controls are activated(Platform Controls Ok)
Step 1Step 2
When the turn tablerotates clockwise (cw) itwill be moving toward you.Make sure you have roomto step backward.
InspectGround Boom
Speed Dial
Turn to full speed Remove wire #16A fromBy-Pass Coil on Main
Hydraulic Valve and retryfunction
Visually checkSpeed Dial for full speed
If full speedIf notfull speed
Remove By-Pass Valvefrom Main Valve and
inspect.Valve is normally closed
If no change
ReplaceSpeed Dial in
Platform
If Ok
Replace Valve If stuck
Go to step 3
If swingok
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 97 UNO 33/ 41 4X4
InspectSwing Switch
Using a meter set toread voltage, while
activating function, checkvoltage on Swing Switch to
Junction Box(wire #23 when swing
is moving in acounterclockwise direction,
wire #24 when swingis moving in a
clockwise direction)Should be 10-12 volts
If no reading
Repair or ReplaceSwing Switch and/orSwing Switch wiring
Step 3
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 98 UNO 33/ 41 4X4
Step 1
Step 2
Go to step 4
Push in on ManualOverride and observe
swing operation
ActivateManual Override
Go to step 2
If still swings erratically
If ok
Swings erratically ineither direction
Replace Solenoid
Supply 12 volts toSolenoid, check if swing is
operating smoothly
InspectSolenoid
Go to step 3
If still swings erraticallyIf ok
Machine function will bemoving when manualoverride is activated.
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 99 UNO 33/ 41 4X4
Step 3Step 4
Install 5000 psi pressuregauge into Swing Brake
Line, while activatingfunction, check pressure.Should maintain steadypressure above 350 psi
InspectSwing Brake
Repair or replaceSwing Brake and/or
Gear Box
If ok
When the turn tablerotates clockwise (cw) itwill be moving toward you.Make sure you have roomto step backward.
InspectSwing Switch Using a meter set to
read voltage, whileactivating function, check
voltage on Swing Switch toJunction Box
(wire #23 when swingis moving in a
counterclockwise direction,wire #24 when swing
is moving in aclockwise direction)
Should be 10-12 volts
If no reading
Repair or ReplaceSwing Switch
and/orSwing Switch wiring
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 100 UNO 33/ 41 4X4
Step 1Step 2
Swings faster one waythan other
Replace Solenoid
Supply 12 volts toSolenoid, check if swing is
operating equally
InspectSolenoid
If still swings faster
Repair or replaceCrossover Relief Valve
Swap Crossover ReliefValves, check for problem
in opposite direction
InspectCrossover Relief
Valve
Go to step 2
If still swings faster
If ok
When the turn tablerotates clockwise (cw) itwill be moving toward you.Make sure you have roomto step backward.
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 101 UNO 33/ 41 4X4
Step 1
Repair or replaceSwing Brake
Visually checkSwing Brake
InspectSwing Brake
If Ok
Swing brake willnot hold
If damaged
Install 5000 psi pressuregauge into Swing BrakeLine, check pressure.
Should be 0 psiCheck Spools onControl Valve for
blocked ports
If 0 psi
Check return Lineand filter for
blockage
If blocked
Repair or replaceas needed
If Ok
If blocked
If above 0 psi
Inspect Counter BalanceCartridge for proper
operation and/or damageto O-rings
Ifdamaged
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 102 UNO 33/ 41 4X4
Go to step 3
Step 1
Step 2
Swings too slow
Go to step 4
Push in on ManualOverride and observe
swing function for fastermovement
ActivateManual Override
Go to step 2
If still swings slowIf
Swingsfaster
Replace Solenoid
Supply 12 volts toSolenoid, check if swing is
operating normally
InspectSolenoid
If still swings slow
Machine function will bemoving when manualoverride is activated.
If swing isnormal
SECTION SIXSWING SYSTEM DIAGNOSTICS
Troubleshooting Guide 103 UNO 33/ 41 4X4
Step 3Step 4
Set for proper speed
Turn speed adjustmentscrew counterclockwise
1 turn.Recheck swing speed
InspectSwing Valve
Go to step 4
If swings fasterIf no
Return to step 1
Install 5000 psi pressuregauge into Swing Brake
Line, while activatingfunction check pressure.Should maintain steadypressure above 350 psi
InspectSwing Brake
Release
Repair or replace SwingBrake
If still swings slowIf ok
SECTION SEVEN:BOOM FUNCTIONS DIAGNOSTICS
SECTION SEVENBOOM FUNCTIONS DIAGNOSTICS
Troubleshooting Guide 107 UNO 33/ 41 4X4
No boom functionsfrom ground control
Go to Page108
InspectBoom Speed Dial
Go to Page108
InspectBy-Pass Valve
OK
Chart 1
Step 1
Step 2
No boom functionsfrom platform
control
Chart 2
Go to Page109
Inspect3-Way Valve
OKStep 3
Go to Page110
InspectBoom Speed Dial
Go to Page110
InspectBy-Pass Valve
OK
Step 1
Step 2
Go to Page111
Inspect3-Way Valve
OKStep 3
SECTION SEVENBOOM FUNCTIONS DIAGNOSTICS
Troubleshooting Guide 108 UNO 33/ 41 4X4
No boom functionsfrom ground control
Step 1Step 2
InspectBy-pass Valve
InspectBoom Speed Dial
Turn to full speed
Remove wire #16A fromBy-Pass Coil on Main
Hydraulic Valve and retryfunction
Visually checkSpeed Dial for full speed
If full speed
If notfull speed
Remove By-Pass Valvefrom Main Valve, inspect
for blown O'ringsor stuck Valve.
Valve is normally closed
If no change
If functionok
ReplaceSpeed Dial in
Platform
Go to step 3
If Ok
Replace Valve If stuck
Go to step 2
SECTION SEVENBOOM FUNCTIONS DIAGNOSTICS
Troubleshooting Guide 109 UNO 33/ 41 4X4
Step 3
Inspect3-Way Valve
Remove Valve and inspectValve is normally closed
With function activated, usea meter set to read voltage,measure voltage on wire#
160C to 3-Way ValveShould read 10-12 volts
If 10-12V
Repair wiring to3-Way Valve
If low orno voltage
SECTION SEVENBOOM FUNCTIONS DIAGNOSTICS
Troubleshooting Guide 110 UNO 33/ 41 4X4
No boom functionsfrom platform control
Step 1Step 2
InspectBy-pass Valve
InspectBoom Speed Dial
Turn to full speed
Remove wire #16 fromBy-Pass Coil on Main
Hydraulic Valve and retryfunction
Visually checkSpeed Dial for full speed
If full speed
If notfull speed
Remove By-Pass Valvefrom Main Valve, inspect
for blown O'ringsor stuck Valve.
Valve is normally closed
If no change
If functionok
ReplaceSpeed Dial in
Platform
Go to step 3
If Ok
Replace Valve If stuck
Go to step 2
SECTION SEVENBOOM FUNCTIONS DIAGNOSTICS
Troubleshooting Guide 111 UNO 33/ 41 4X4
Step 3
Inspect3-Way Valve
Remove Valve and inspectValve is normally closed
With function activated, usea meter set to read voltage,measure voltage on wire#
160C to 3-Way ValveShould read 10-12 volts
If 10-12V
Repair wiring to3-Way Valve
If low orno voltage
SECTION EIGHT:PLATFORM LEVELING SYSTEM DIAGNOSTICS
SECTION EIGHTPLATFORM LEVELING SYSTEM DIAGNOSTICS
Troubleshooting Guide 115 UNO 33/ 41 4X4
Platform will notmaintain level as
boomraises or lowers
Go to Page117
InspectHydraulic Oil Temperature
Go to Page117
InspectHolding Valves
Platform will notmaintain level with
machine offGo to Page
118
InspectHolding Valves in
Slave Level Cylinder
OK
Chart 1
Chart 2
Step 1
Step 2
Step 1
Platform level willnot work fromground control
(PlatformControl Ok)
Go to Page119
InspectGround Control Switch
Go to Page119
InspectLevel Switch
OK
Chart 3
Step 1
Step 2
Platform level willnot work from
platform control(Ground Control Ok)
Go to Page120
InspectPlatform Level Switch
Chart 4
Step 1
SECTION EIGHTPLATFORM LEVELING SYSTEM DIAGNOSTICS
Troubleshooting Guide 116 UNO 33/ 41 4X4
Platform levelup function is
inoperativeGo to Page
121Activate
Manual Override
Go to Page121
InspectSolenoid Valve
Go to Page122
InspectPressure to Cylinder
Platform leveldown function is
inoperativeGo to Page
123Activate
Manual Override
Go to Page123
InspectSolenoid Valve
Go to Page124
InspectPressure to Cylinder
OK
OK
Chart 5
Chart 6
Step 1
Step 2
Step 3
Step 1
Step 2
Step 3
OK
OK
SECTION EIGHTPLATFORM LEVELING SYSTEM DIAGNOSTICS
Troubleshooting Guide 117 UNO 33/ 41 4X4
InspectHydraulic OilTemperature
Cycle the boom a fewtimes to warm up the
hydraulic oil
Hydraulic Oil is cold
If cold
The platform does notmaintain level as boomraises or lowers
Step 1Step 2
InspectHolding Valves inMain Hydraulic
Valve
Repair or replaceHolding Valves and/or
Check Valves
With platform level andboom fully down, remove
the hoses from MainHydraulic Valve, plughoses and cap valve.
Raise boom 5 ft. and notethe Platform Leveling
System.
If Level System performs normallyIf Level Systemperforms
abnormally
Repair or replaceSeals in Master Leveling
System
If problemstill existsGo to step 2
SECTION EIGHTPLATFORM LEVELING SYSTEM DIAGNOSTICS
Troubleshooting Guide 118 UNO 33/ 41 4X4
The platform will notmaintain level withmachine off
Step 1
InspectHolding Valves in
Slave LevelCylinder
Repair or replaceHolding Valves
Place a safe work loadin platform and
remove the hoses toSlave Level Cylinder
Observe the Platform.If oil leaks and platform drifts
If no oil leaksbut platform
still drifts
Repair or replaceLevel Cylinder
SECTION EIGHTPLATFORM LEVELING SYSTEM DIAGNOSTICS
Troubleshooting Guide 119 UNO 33/ 41 4X4
Step 1
Platform level will notwork from ground control(Platform Control Ok)
Step 2
InspectGround Control
Switch
Check continuity on wire#28A between Ground
Control Switch andPlatform Level Switch
Using meter set to readvoltage, activate Ground
Control Switch andmeasure voltage on
wire #28A entering PlatformLevel Switch
Should read 10-12 volts
If no readingRepair or replaceGround Control
Switchand/or
Ground ControlSwitch wiring
Go to step 2 If10-12V
Nocontinuity
InspectLevel Switch
Using meter set to readvoltage, activate
Level Down and measurevoltage on
wire #13 at Junction BoxShould read 10-12 volts
If no reading
Repair or replacePlatform Level Switch
and/orPlatform Level Switchwiring to Junction Box
SECTION EIGHTPLATFORM LEVELING SYSTEM DIAGNOSTICS
Troubleshooting Guide 120 UNO 33/ 41 4X4
Measure voltage on wires#12 and #13 leaving
Platform Level SwitchShould read 10-12 volts
If lowor no
voltage
Step 1
ReplaceLevel Switch
Using a meterset to read voltage,measure voltage on
wire #9 enteringPlatform Level Switch
Should read 10-12 volts
InspectPlatform Level
Switch
Platform level will not workfrom platform control(Ground Control Ok)
If 10-12V
ReplaceFoot Switch
If lowor no
voltage
SECTION EIGHTPLATFORM LEVELING SYSTEM DIAGNOSTICS
Troubleshooting Guide 121 UNO 33/ 41 4X4
Repair or replacewire #13
Using a meterset to read voltage,
measure voltage on wire#13 between Level Switch
and Solenoid ValveShould be 10-12 volts
InspectSolenoid Valve
If no readingIf
10-12V
Repair or replaceSolenoid Valve
Step 1Step 2
Platform level upfunction is inoperative
Go to step 2
Push in on ManualOverride and observe
Platform level up function
ActivateManual Override
Go to step 3
If okIf problemstill exists
Machine function will bemoving when manualoverride is activated.
SECTION EIGHTPLATFORM LEVELING SYSTEM DIAGNOSTICS
Troubleshooting Guide 122 UNO 33/ 41 4X4
Step 3
Install 5000 psi pressuregauge at Port 2 of SlaveLevel Cylinder. Activatefunction and measure
pressure to Slave LevelCylinder.
Should read 2000 psiwhen fully extended.
InspectPressure to
Cylinder
If low or no reading
Remove hose from Port 6on Slave Level Cylinder,plug hose and cap Slave
Level Cylinder.Recheck pressure
Should read 2000 psiwhen fully extended.
Repair or replaceRelief Valve in
Reduced PressureManifold
Repair or replaceSlave Level
Cylinder
If lowor no
reading
Return to Step 1If lowor no
reading
If1500 psi
SECTION EIGHTPLATFORM LEVELING SYSTEM DIAGNOSTICS
Troubleshooting Guide 123 UNO 33/ 41 4X4
Step 1Step 2
Platform level downfunction is inoperative
Repair or replaceWire #12
Using a meterset to read voltage,
measure voltage on wire#12 between Level Switch
and Solenoid ValveShould be 10-12 volts
InspectSolenoid Valve
If no readingIf10-12V
Repair or replaceSolenoid Valve
Go to step 2
Push in on ManualOverride and observePlatform Level down
function
ActivateManual Override
Go to step 3
If okIf problemstill exists
Machine function will bemoving when manualoverride is activated.
SECTION EIGHTPLATFORM LEVELING SYSTEM DIAGNOSTICS
Troubleshooting Guide 124 UNO 33/ 41 4X4
Step 3
Install 5000 psi pressuregauge at Port 1 of SlaveLevel Cylinder. Activatefunction and measure
pressure to Slave LevelCylinder.
Should read 2000 psiwhen fully retracted.
InspectPressure to
Cylinder
If low or no reading
Remove hose from Port 2on Slave Level Cylinder,plug hose and cap Slave
Level Cylinder.Recheck pressure
Should read 2000 psiwhen fully retracted.
Repair or replaceRelief Valve in
Reduced PressureManifold
Repair or replaceSlave Level
Cylinder
If lowor no
reading
If1500 psi
Return to Step 1If lowor no
reading
SECTION NINE:BOOM ELEVATION SYSTEM DIAGNOSTICS
SECTION NINEBOOM ELEVATION SYSTEM DIAGNOSTICS
Troubleshooting Guide 127 UNO 33/ 41 4X4
Boom raises but willnot stay elevated
(Bottom /Middle/Top)
Go to Page129
InspectManual Bleed Down
Go to Page129
InspectHolding Valve
Bottom boom willnot raise from
platform control(Ground Control Ok)
Go to Page131
InspectBoom Lift Switch
Go to Page131
InspectLift/Swing Speed Valve
OK
OK
Chart 1
Chart 2
Step 1
Step 2
Step 1
Step 2
InspectSeals in Cylinder
OKStep 3
Go to Page130
Middle boom will notraise from
platform control(Ground Control Ok)
(Uno 41 only)
Go to Page132
InspectBoom Lift Switch
Go to Page132
InspectLift/Swing Speed Valve
OK
Chart 3
Step 1
Step 2
Top boom will notraise from
platform control(Ground Control Ok)
Go to Page133
InspectBoom Lift Switch
Go to Page133
InspectLift/Swing Speed Valve
OK
Chart 4
Step 1
Step 2
SECTION NINEBOOM ELEVATION SYSTEM DIAGNOSTICS
Troubleshooting Guide 128 UNO 33/ 41 4X4
Bottom boom willnot raise fromground control
Go to Page134
InspectBoom Lift Switch
Chart 5
Step 1
Go to Page135
Inspect3-Way Valve
OKStep 3
Go to Page134
InspectBy-Pass Valve
OKStep 2
Middle boom will notraise from
ground control(Uno 41 only)
Chart 6
Top boom will notraise from
ground control
Chart 7
Go to Page135
InspectLift Control Valve
OKStep 4
Go to Page136
InspectBoom Lift Switch
Step 1
Go to Page137
Inspect3-Way Valve
OKStep 3
Go to Page136
InspectBy-Pass Valve
OKStep 2
Go to Page137
InspectLift Control Valve
OKStep 4
Go to Page138
InspectBoom Lift Switch
Step 1
Go to Page139
Inspect3-Way Valve
OKStep 3
Go to Page138
InspectBy-Pass Valve
OKStep 2
Go to Page139
InspectLift Control Valve
OKStep 4
SECTION NINEBOOM ELEVATION SYSTEM DIAGNOSTICS
Troubleshooting Guide 129 UNO 33/ 41 4X4
Boom raises but will not stayelevated (Bottom /Middle/Top)
Step 1Step 2
Go to step 2
InspectManual Bleed
Down
Turn Manual Bleed DownValve clockwise until
valve is closed
Problem still exist
ReplaceHolding Valve and/or
Seal Kit
InspectHolding Valve
Raise boom approximately2 ft, remove hose to
#2 port on Lift Cylinder,observe for leakage
Leakage
Go to step 3
Raise boom approximately2 ft. and mark Lift Cylinder.Remove hose from port #2on Lift Cylinder. Observe oil
leakage.
Problem still exist
Repair or replaceManual Bleed
DownLeakage
Problemstill exist
SECTION NINEBOOM ELEVATION SYSTEM DIAGNOSTICS
Troubleshooting Guide 130 UNO 33/ 41 4X4
Step 3
Repair or replaceCylinder
InspectSeals in Cylinder
Remove steel tube onCylinder, check if oil isleaking from upper port
If leaking
SECTION NINEBOOM ELEVATION SYSTEM DIAGNOSTICS
Troubleshooting Guide 131 UNO 33/ 41 4X4
Step 1Step 2
Bottom boom will not raisefrom platform control(Ground Control Ok)
Measure voltage on wire#28 to Lift Switch
Should read 10 to 12 volts
InspectBoom Lift Switch
Using meter set toread voltage, measure
voltage on wire #22Should read 10 to 12 volts
If no reading
If 10 to 12VCheck continuityon wire betweenLift Switch andGround Control
Box
If no reading
Repair or replace Lift Switch
No continuity
Repair or replaceWire #22
While activating boomfunction, use a meter set to
read voltage, measurevoltage on wire #16B at
By-Pass Coil.Should read 0 volts
Visually check Speed Dialin platform Control Box for
fast speed.Dial should be set to fast
InspectBoom Speed Dial
Replace Dial
If Ok
If10-12V
If Ok
While activatingLift function,
measure voltageon wire #160C at
3-Way Valve.Should read 10-12
volts
If no voltage
Repair wire toGround Control
Box
Remove Valve, visuallycheck to insure that it ismoving when power is
applied and that O'Ringsare ok.
If bad
Repair or replace asneeded
Go to step 2
If continuityexists
If 0V
SECTION NINEBOOM ELEVATION SYSTEM DIAGNOSTICS
Troubleshooting Guide 132 UNO 33/ 41 4X4
Step 1Step 2
Middle boom will not raisefrom platform control(Ground Control Ok)(Uno 41 only)
Measure voltage on wire#28 to Lift Switch
Should read 10 to 12 volts
InspectBoom Lift Switch
Using meter set toread voltage, measurevoltage on wire #22B
Should read 10 to 12 volts
If no reading
If 10 to 12VCheck continuityon wire betweenLift Switch andGround Control
Box
If no reading
Repair or replace Lift Switch
No continuity
Repair or replaceWire #22B
While activating boomfunction, use a meter set to
read voltage, measurevoltage on wire #16B at
By-Pass Coil.Should read 0 volts
Visually check Speed Dialin platform Control Box for
fast speed.Dial should be set to fast
InspectBoom Speed Dial
Replace Dial
If Ok
If10-12V
If Ok
While activatingLift function,
measure voltageon wire #160C at
3-Way Valve.Should read 10-12
volts
If no voltage
Repair wire toGround Control
Box
Remove Valve, visuallycheck to insure that it ismoving when power is
applied and that O'Ringsare ok.
If bad
Repair or replace asneeded
Go to step 2
If continuityexists
If 0V
SECTION NINEBOOM ELEVATION SYSTEM DIAGNOSTICS
Troubleshooting Guide 133 UNO 33/ 41 4X4
Step 1Step 2
Top boom will not raise fromplatform control(Ground Control Ok)
Measure voltage on wire#28 to Lift Switch
Should read 10 to 12 volts
InspectBoom Lift Switch
Using meter set toread voltage, measurevoltage on wire #22A
Should read 10 to 12 volts
If no reading
If 10 to 12VCheck continuityon wire betweenLift Switch andGround Control
Box
If no reading
Repair or replace Lift Switch
No continuity
Repair or replaceWire #22A
While activating boomfunction, use a meter set to
read voltage, measurevoltage on wire #16B at
By-Pass Coil.Should read 0 volts
Visually check Speed Dialin platform Control Box for
fast speed.Dial should be set to fast
InspectBoom Speed Dial
Replace Dial
If Ok
If10-12V
If Ok
While activatingLift function,
measure voltageon wire #160C at
3-Way Valve.Should read 10-12
volts
If no voltage
Repair wire toGround Control
Box
Remove Valve, visuallycheck to insure that it ismoving when power is
applied and that O'Ringsare ok.
If bad
Repair or replace asneeded
Go to step 2
If continuityexists
If 0V
SECTION NINEBOOM ELEVATION SYSTEM DIAGNOSTICS
Troubleshooting Guide 134 UNO 33/ 41 4X4
Bottom boom will not raisefrom ground control
Step 1
Measure voltage on wire#28 to Lift Switch
Should read 10 to 12 volts
InspectBoom Lift Switch
Using meter set toread voltage, measure
voltage on wire #22Should read 10 to 12 volts
If no reading
If 10 to 12VCheck continuityon wire between
Lift Switch and LiftValve
If no reading
Repair or replace Lift Switch
No continuity
Repair or replaceWire #22 and retry
function
Using a meter set toread voltage, measure
voltage on wire #16B to By-Pass Valve
Should read 0 volts
InspectBy-Pass Valve
RepairSwitch and/or Wire
Ifvoltage
If 0V
Remove Valve from ControlValve, visually check for
proper operation.Valve is normally closed
If Ok
Go to step 3
If valveis stuckReplace Valve
If 10 to 12V
If still no function
Go to step 2
Step 2
SECTION NINEBOOM ELEVATION SYSTEM DIAGNOSTICS
Troubleshooting Guide 135 UNO 33/ 41 4X4
Step 3
Install a 5000 psi pressuregauge on test port,
operate function andcheck pressure.
Should read 2400 psi
InspectLift Control Valve
Activate manual overrideon Valve, observe boom
movement
If boom does not move
If boomoperatesReplace
Lift Solenoid
If low reading
Remove hose from #2 Portof Lift Cylinder, plug hoseand cap cylinder. Recheck
pressure
If pressureis Ok
Repair or replaceLift Cylinder
Machine function will bemoving when manualoverride is activated.
Step 4
Using a meter set toread voltage, measure
voltage on wire #160C at3-Way Valve
Should read 10-12 volts
Inspect3-Way Valve
Repair or replace Wire to valve
Ifvoltage
If 10-12V
Remove Valve fromControl Valve, visually
check for stuck valve orblown O-rings.
Valve is normally closedIf Ok
Go to step 4
If badReplace Valve
SECTION NINEBOOM ELEVATION SYSTEM DIAGNOSTICS
Troubleshooting Guide 136 UNO 33/ 41 4X4
Middle boom will not raisefrom ground control(Uno 41 only)
Step 1
Measure voltage on wire#28 to Lift Switch
Should read 10 to 12 volts
InspectBoom Lift Switch
Using meter set toread voltage, measurevoltage on wire #22B
Should read 10 to 12 volts
If no reading
If 10 to 12VCheck continuityon wire between
Lift Switch and LiftValve
If no reading
Repair or replace Lift Switch
No continuity
Repair or replaceWire #22B andretry function
Using a meter set toread voltage, measure
voltage on wire #16B to By-Pass Valve
Should read 0 volts
InspectBy-Pass Valve
RepairSwitch and/or Wire
Ifvoltage
If 0V
Remove Valve from ControlValve, visually check for
proper operation.Valve is normally closed
If Ok
Go to step 3
If valveis stuckReplace Valve
If 10 to 12V
If still no function
Go to step 2
Step 2
SECTION NINEBOOM ELEVATION SYSTEM DIAGNOSTICS
Troubleshooting Guide 137 UNO 33/ 41 4X4
Step 3
Install a 5000 psi pressuregauge on test port,
operate function andcheck pressure.
Should read 2400 psi
InspectLift Control Valve
Activate manual overrideon Valve, observe boom
movement
If boom does not move
If boomoperatesReplace
Lift Solenoid
If low reading
Remove hose from #2 Portof Lift Cylinder, plug hoseand cap cylinder. Recheck
pressure
If pressureis Ok
Repair or replaceLift Cylinder
Machine function will bemoving when manualoverride is activated.
Step 4
Using a meter set toread voltage, measure
voltage on wire #160C at3-Way Valve
Should read 10-12 volts
Inspect3-Way Valve
Repair or replace Wire to valve
Ifvoltage
If 10-12V
Remove Valve fromControl Valve, visually
check for stuck valve orblown O-rings.
Valve is normally closedIf Ok
Go to step 4
If badReplace Valve
SECTION NINEBOOM ELEVATION SYSTEM DIAGNOSTICS
Troubleshooting Guide 138 UNO 33/ 41 4X4
Top boom will not raisefrom ground control
Step 1
Measure voltage on wire#28 to Lift Switch
Should read 10 to 12 volts
InspectBoom Lift Switch
Using meter set toread voltage, measurevoltage on wire #22A
Should read 10 to 12 volts
If no reading
If 10 to 12VCheck continuityon wire between
Lift Switch and LiftValve
If no reading
Repair or replace Lift Switch
No continuity
Repair or replaceWire #22A andretry function
Using a meter set toread voltage, measure
voltage on wire #16B to By-Pass Valve
Should read 0 volts
InspectBy-Pass Valve
RepairSwitch and/or Wire
Ifvoltage
If 0V
Remove Valve from ControlValve, visually check for
proper operation.Valve is normally closed
If Ok
Go to step 3
If valveis stuckReplace Valve
If 10 to 12V
If still no function
Go to step 2
Step 2
SECTION NINEBOOM ELEVATION SYSTEM DIAGNOSTICS
Troubleshooting Guide 139 UNO 33/ 41 4X4
Step 3
Install a 5000 psi pressuregauge on test port,
operate function andcheck pressure.
Should read 2400 psi
InspectLift Control Valve
Activate manual overrideon Valve, observe boom
movement
If boom does not move
If boomoperatesReplace
Lift Solenoid
If low reading
Remove hose from #2 Portof Lift Cylinder, plug hoseand cap cylinder. Recheck
pressure
If pressureis Ok
Repair or replaceLift Cylinder
Machine function will bemoving when manualoverride is activated.
Step 4
Using a meter set toread voltage, measure
voltage on wire #160C at3-Way Valve
Should read 10-12 volts
Inspect3-Way Valve
Repair or replace Wire to valve
Ifvoltage
If 10-12V
Remove Valve fromControl Valve, visually
check for stuck valve orblown O-rings.
Valve is normally closedIf Ok
Go to step 4
If badReplace Valve
SECTION TEN:TELESCOPE SYSTEM DIAGNOSTICS
SECTION TENTELESCOPE SYSTEM DIAGNOSTICS
Troubleshooting Guide 143 UNO 33/ 41 4X4
Chart 1
Boom will notretract from
ground controlActivate
Manual Override
InspectExtend and Retract Switch
InspectRetract Solenoid
OK
OK
Step 1
Step 2
Step 3
Boom will notretract from
platform control(Ground Control Ok)
ActivateManual Override
InspectExtend and Retract Switch
InspectWiring in Hose Carrier
OK
OK
Step 1
Step 2
Step 3
Chart 2
Go to Page145
Go to Page145
Go to Page146
Go to Page148
Go to Page148
Go to Page149
InspectBoom Speed Dial and Valve
Inspect3-Way Valve
OK
OK
Step 4
Step 5
Go to Page146
Go to Page147
InspectExtend/Retract Valve
OKStep 6
Go to Page147
SECTION TENTELESCOPE SYSTEM DIAGNOSTICS
Troubleshooting Guide 144 UNO 33/ 41 4X4
Boom will notextend from
platform control(Ground Control Ok)
Go to Page153
ActivateManual Override
Go to Page153
InspectExtend and Retract Switch
Go to Page154
InspectWiring in Hose Carrier
OK
OK
Step 1
Step 2
Step 3
Chart 4
Boom drifts in Go to Page155
InspectHolding Valves for Extend
Step 1
Chart 5
Go to Page155
InspectCylinder for Internal Leakage
OKStep 2
Boom will notextend from
ground controlActivate
Manual Override
InspectExtend and Retract Switch
InspectExtend Solenoid
OK
OK
Step 1
Step 2
Step 3
Chart 3
Go to Page150
Go to Page150
Go to Page151
InspectBoom Speed Dial and Valve
OKStep 4
Go to Page151
Inspect3-Way Valve
OKStep 5
Go to Page152
InspectExtend/Retract Valve
OKStep 6
Go to Page152
SECTION TENTELESCOPE SYSTEM DIAGNOSTICS
Troubleshooting Guide 145 UNO 33/ 41 4X4
Boom will not retractfrom ground control
Step 1Step 2
Go to step 2
Activate Ground ControlSwitch, push in on
Manual Override andobserve boom movement
ActivateManual Override
If retracting
Go to step 3 If10-12V
Repair or replaceExtend and
Retract Switch
InspectExtend and
Retract Switch
Using meter set to readvoltage, measure voltage
at wire #15 atExtend and Retract
SwitchShould read 10-12 volts
If no reading
Machine function will bemoving when manualoverride is activated.
Go to step 4 If nomovement
SECTION TENTELESCOPE SYSTEM DIAGNOSTICS
Troubleshooting Guide 146 UNO 33/ 41 4X4
Step 3
Repair or replaceWire to Valve
InspectRetract Solenoid
Using meter set to readvoltage, activate functionand measure voltage on
wire #15 to RetractSolenoid
Should read 10-12 volts
If no reading
If 10-12VReplace
Retract Solenoid
Step 4Inspect
Boom Speed Dialand Valve
Turn to full speedRemove wire #16B from
By-Pass Coil on MainHydraulic Valve and retry
function
Visually checkSpeed Dial for full speed
If full speedIf not
full speed
Remove By-Pass Valvefrom Main Valve and
inspect. Valve is normallyclosed
If no change
If retractok
ReplaceSpeed Dial in
Platform
Activate Manual Overrideon Valve while activating
Steer function
If Ok
Replace Valve If stuck
Go to step 5 If Ok
Go to step 6
If function does not operate
SECTION TENTELESCOPE SYSTEM DIAGNOSTICS
Troubleshooting Guide 147 UNO 33/ 41 4X4
Step 5
Install a 5000 psi pressuregauge on test port,
operate function andcheck pressure.
Should read 2400 psi
InspectExtend/Retract
Valve
Repair or replaceExtend Cylinderand/or Holding
Valve
If low or no pressure
Remove hose from RetractPort of Control Valve, plug
hose and cap valve.Recheck pressure
Ifpressure
Ok
AdjustPump Main System Relief
If low or no pressure
Step 6
Using a meter set toread voltage, measure
voltage on wire #160C at3-Way Valve
Should read 10-12 volts
Inspect3-Way Valve
Repair or replace Wire to valve
Ifvoltage
If 10-12V
Remove Valve fromControl Valve, visually
check for stuck valve orblown O-rings.
Valve is normally closedIf Ok
Go to step 6
If badReplace Valve
SECTION TENTELESCOPE SYSTEM DIAGNOSTICS
Troubleshooting Guide 148 UNO 33/ 41 4X4
Boom will not retractfrom platform control(Ground Control Ok)
Step 1Step 2
Machine function will bemoving when manualoverride is activated.
Go to step 2
Activate Ground ControlSwitch, push in on
Manual Override andobserve boom movement
ActivateManual Override
If retracting
Go to step 3 If10-12V
Repair or replaceExtend and
Retract Switch
InspectExtend and
Retract Switch
Using meter set to readvoltage, measure voltage
at wire #15 atExtend and Retract
SwitchShould read 10-12 volts
If no reading
Go to Chart 1step 4 and 5
If10-12V
SECTION TENTELESCOPE SYSTEM DIAGNOSTICS
Troubleshooting Guide 149 UNO 33/ 41 4X4
Step 3
Repair or replaceWiring in Hose Carrier
InspectWiring in Hose
Carrier
Using meter set to readvoltage, activate functionand measure voltage at
wire #15 inGround Control Box
Should read 10-12 volts
If no reading
SECTION TENTELESCOPE SYSTEM DIAGNOSTICS
Troubleshooting Guide 150 UNO 33/ 41 4X4
Boom will not extendfrom ground control
Step 1Step 2
Machine function will bemoving when manualoverride is activated.
Go to step 2
Activate Ground ControlSwitch, push in on
Manual Override andobserve boom movement
ActivateManual Override
If extending
Go to step 3 If10-12V
Repair or replaceExtend and
Retract Switch
InspectExtend and
Retract Switch
Using meter set to readvoltage, measure voltage
at wire #14 atExtend and Retract
SwitchShould read 10-12 volts
If no reading
Go to step 4 If nomovement
SECTION TENTELESCOPE SYSTEM DIAGNOSTICS
Troubleshooting Guide 151 UNO 33/ 41 4X4
Step 3
Repair or replaceWire to Valve
InspectExtend Solenoid
Using meter set to readvoltage, activate functionand measure voltage on
wire #14 to ExtendSolenoid
Should read 10-12 volts
If no reading
If 10-12VReplace
Extend Solenoid
InspectBoom Speed Dial
and Valve
Turn to full speedRemove wire #16B from
By-Pass Coil on MainHydraulic Valve and retry
function
Visually checkSpeed Dial for full speed
If full speedIf not
full speed
Remove By-Pass Valvefrom Main Valve and
inspect. Valve is normallyclosed
If no change
If steerok
ReplaceSpeed Dial in
Platform
Activate Manual Overrideon Valve while activating
Steer function
If Ok
Replace Valve If stuck
Go to step 5
If function does not operate
Step 4
SECTION TENTELESCOPE SYSTEM DIAGNOSTICS
Troubleshooting Guide 152 UNO 33/ 41 4X4
Step 5
Install a 5000 psi pressuregauge on test port,
operate function andcheck pressure.
Should read 2400 psi
InspectExtend/Retract
Valve
Repair or replaceExtend Cylinderand/or Holding
Valve
If low or no pressure
Remove hose from RetractPort of Control Valve, plug
hose and cap valve.Recheck pressure
Ifpressure
Ok
AdjustPump Main System Relief
If low or no pressure
Step 6
Using a meter set toread voltage, measure
voltage on wire #160C at3-Way Valve
Should read 10-12 volts
Inspect3-Way Valve
Repair or replace Wire to valve
Ifvoltage
If 10-12V
Remove Valve fromControl Valve, visually
check for stuck valve orblown O-rings.
Valve is normally closedIf Ok
Go to step 6
If badReplace Valve
SECTION TENTELESCOPE SYSTEM DIAGNOSTICS
Troubleshooting Guide 153 UNO 33/ 41 4X4
Boom will not extendfrom platform control(Ground Control Ok)
Step 1Step 2
Machine function will bemoving when manualoverride is activated.
Go to step 2
Activate Ground ControlSwitch, push in on
Manual Override andobserve boom movement
ActivateManual Override
If extending
Go to step 3 If12V
Repair or replaceExtend and
Retract Switch
InspectExtend and
Retract Switch
Using meter set to readvoltage, measure voltage
at wire #14 atExtend and Retract
SwitchShould read 10-12 volts
If no reading
Go to Chart 3step 4 and 5
If10-12V
SECTION TENTELESCOPE SYSTEM DIAGNOSTICS
Troubleshooting Guide 154 UNO 33/ 41 4X4
Step 3
Repair or replaceWiring in Hose Carrier
InspectWiring in Hose
Carrier
Using meter set to readvoltage, activate functionand measure voltage on
wire #14 inGround Control Box
Should read 10-12 volts
If no reading
SECTION TENTELESCOPE SYSTEM DIAGNOSTICS
Troubleshooting Guide 155 UNO 33/ 41 4X4
Boom drifts in
Step 1
Repair or replaceHolding Valves
and/orO-rings
Visually check for blownO-Rings
If stuck and/or blown
Repair or replaceSeals in Extend Cylinder
Raise boom and extendboom 2 ft., remove hoses
from Extend Control Valve.Observe oil leakage
InspectSeals in Extend
Cylinder
Leakage from Port 1of Extend Cylinder
Repair or replaceHolding Valve
Leakagefrom Port 2of ExtendCylinder
Step 2
Go to step 2
If Ok
InspectHolding Valves for
Extend
SECTION ELEVEN: FUEL SYSTEM DIAGNOSTICS
SECTION ELEVENFUEL SYSTEM DIAGNOSTICS
Troubleshooting Guide 159 UNO 33/ 41 4X4
Engine will notstart on Gasoline,
but will starton L.P.
Go to Page160
InspectFuel Level
Go to Page160
InspectDual Fuel Switch
Engine will notstart on L.P.,
but will start onGasoline.
Go to Page162
InspectL.P. Gauge
Go to Page162
InspectDual Fuel Switch
Chart 2
Chart 1
OK
OK
Go to Page161
InspectFuel Shutoff Valve
OK
Go to Page163
InspectL.P. Filter Lock
OK
SECTION ELEVENFUEL SYSTEM DIAGNOSTICS
Troubleshooting Guide 160 UNO 33/ 41 4X4
Engine will not starton Gasoline, but willstart on L.P.
Step 1Step 2
Fill tank with Gasoline
InspectFuel Level
Visually check FuelGauge to verify an
adequate amount of fuelis in tank
If not
Go to step 2
If yes
Repair or replaceDual Fuel Switch
InspectDual Fuel Switch
Using meter set to readvoltage, measure voltage1. on wire #77A at the
Dual Fuel Switch2. on wire #78 coming
out of Dual Fuel SwitchShould read 10-12 voltsGo to step 3 If
10-12V
If no reading
SECTION ELEVENFUEL SYSTEM DIAGNOSTICS
Troubleshooting Guide 161 UNO 33/ 41 4X4
Step 3
Repair or replaceFuel Shutoff Valve
InspectFuel Shutoff
Valve
Using meter set to readvoltage, measure voltage
on wire #78 at theFuel Shutoff Valve
Should read 10-12 voltsRepairwire to Valve
If noreading
If 10-12V
SECTION ELEVENFUEL SYSTEM DIAGNOSTICS
Troubleshooting Guide 162 UNO 33/ 41 4X4
Engine will not starton L.P., but will starton Gasoline.
Step 1Step 2
Fill tank with L.P.
InspectL.P. Gauge
Visually checkL.P. Gauge to verify an
adequate amount of fuel is in tank
If not
Go to step 2
If yes
Repair or replaceDual Fuel Switch
InspectDual Fuel Switch
Using meter set to readvoltage, measure voltage1. on wire #77A at the
Dual Fuel Switch2. on wire #77B coming
out of Dual Fuel SwitchShould read 10-12 voltsGo to step 3 If
10-12V
If no reading
SECTION ELEVENFUEL SYSTEM DIAGNOSTICS
Troubleshooting Guide 163 UNO 33/ 41 4X4
Step 3
Repair or replaceL.P. Filter Lock
InspectL.P. Filter Lock
Using meter set to readvoltage, measure voltage1. on wire #77B at the
L.P. Filter Lock2. on wire #78 coming
out of Dual Fuel SwitchShould read 10-12 volts
Repairwire to Valve
If noreading
If 10-12V
SECTION TWELVE:ACCESSORIES DIAGNOSTICS
SECTION TWELVEACCESSORIES DIAGNOSTICS
Troubleshooting Guide 167 UNO 33/ 41 4X4
Machine will notsteer
Go to Page168
InspectTow Package Float Valve
Step 1
Chart 3
AC Generator haslow voltage
Go to Page169
InspectAC Voltage from Generator
Step 1
Chart 2
AC Generatorwill not function
Go to Page168
InspectPower to Generator Switch
at Platform
Go to Page168
InspectGenerator Solenoid
OK
Step 1
Step 2
Chart 1
SECTION TWELVEACCESSORIES DIAGNOSTICS
Troubleshooting Guide 168 UNO 33/ 41 4X4
AC Generator willnot function
Step 1Step 2
Repair or replaceGenerator Switch at
Platform
InspectPower to
Generator Switchat Platform
Using meter set to readvoltage, measure voltage
at wire #169 whenswitch is activated toGenerator position
Should read 10-12 volts
If no reading
Go to step 2
If10-12V
Repair or replaceWire from Platform
InspectGeneratorSolenoid
Using meter set to readvoltage, measure voltage
on Generator Solenoidwire #169
Should read 10-12 volts
If no reading
Repair or replaceSolenoid Valve
If10-12V
SECTION TWELVEACCESSORIES DIAGNOSTICS
Troubleshooting Guide 169 UNO 33/ 41 4X4
Step 1
AC Generator haslow voltage
Adjust Speed ControlValve on HydraulicGenerator Valve
counterclockwise toincrease voltage
InspectAC Voltage from
GeneratorUsing meter set to read
voltage, measure voltageat Generator
Should read 130 volts AC
If no reading
SECTION TWELVEACCESSORIES DIAGNOSTICS
Troubleshooting Guide 170 UNO 33/ 41 4X4
Step 1
Machine willnot steer
Check decal for correctpositioning
InspectTow PackageFloat Valve
Visually inspect TowPackage Float Valveto insure valve is inoperational position
No
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