Page 114
45-J Desel - Servce & Parts Manual
January 2022
Secton 19 - Troubleshootng
Problem
Possible Cause
Remedy/Solution
Boom Extend/Retract
No boom extension
Excessive weight on platform
Reduce weight to within platform capacity
Level sensor out of level (platform
elevated above 10’)
Indicator light will be illuminated and alarm will sound off.
Reposition machine to level ground
Main relief valve (6) out of
adjustment
Adjust main relief valve (6) to rated platform capacity located on function
manifold - See Section 10 - Hydraulic System.
Solenoid valve (18) (dump valve)
not energized
Check wiring to valve. Check EZ-Cal ref. P4-14 for output
Ext/Retract valve (8.2) not
energized
Check wiring to lift valve. Check for EZ-Cal message or flash code.
Extend/Retract valve (8.2) not
shifting
Clean debris. Check for damage/replace.
Ext/Retract joystick inoperative
Check joystick output using EZ-Cal ref. 2D-2, P14-1 & P14-2 for upper
control analog output signal
Battery discharged - no charge
output
Check battery voltage, alternator output (14.5 volts). Check GP400 for 4-4
flash code.
System interlock
Check EZ-Cal HELP messages for interlock
Boom extends/retracts
slow
Excessive weight on Platform
Reduce weight to rated platform capacity
Main relief valve (6) out of
adjustment
Adjust extend relief valve (See Section 10 - Hydraulic System) located on
function manifold.
Extend/Retract valve (8.2) not
shifting completely
Clean debris. Check for damage/replace.
Extend Speed adjustment reduced
in GP400 Module
Use the EZ-Cal and check/adjust setting.
See ADJUSTMENTS/TELESCOPE OUT MAX
No boom retract
Main relief valve (6) out of
adjustment
Adjust main relief valve (6) to rated platform capacity located on function
manifold - See Section 10 - Hydraulic System.
Foreign debris stuck in boom slide
pads
Inspect/ clean slide pads.
Solenoid valve (18) (dump valve)
not energized
Check wiring to valve. Check EZ-Cal ref. P4-14 for output.
Ext/Retract valve (8.2) not
energized
Check wiring to lift valve. Check for EZ-Cal message or flash code.
Extend/Retract valve (8.2) not
shifting
Clean debris. Check for damage/replace.
Ext/Retract joystick inoperative
Check joystick output using EZ-Cal ref. 2D-2, P14-1 & P14-2 for upper
control analog output signal.
Battery discharged - no charge
output
Check battery voltage, alternator output (14.5 volts). Check GP400 for 4-4
flash code.
System interlock
Check EZ-Cal HELP messages for interlock
Problem
Possible Cause
Remedy/Solution
Platform Auto-Level
Platform will not remain
level while elevating or
lowering platform (level
cylinder not moving at all)
Platform Level solenoid (19) valve
not energized
Check wiring to valve. Check output from VCCM P-1.
Platform Level solenoid valve (19)
sticking
Remove valve and inspect for debris or damage. Replace valve located
up on the side of the boom.
Counterbalance valve faulty
Valve must not be tampered with. Replace valve.
Flow Compensator valve (20) not
shifting
Clean debris. Check for damage/replace.
Platform will not remain
level while elevating or
lowering platform (level
cylinder moving too slow
or fast)
Excessive weight on platform
Reduce weight to within platform capacity
Main relief valve (16) out of
adjustment
Adjust main relief valve (See Section 10 - Hydraulic System) located on
function manifold.
Platform level solenoid valve (19)
not shifting completely
Clean debris. Check for damage/replace.
