SECTION 3 - TROUBLESHOOTING
3-2
– JLG Lift –
3120743
Table 3-1.Platform Assembly - Troubleshooting
TROUBLESHOOTING CHART
TROUBLE
PROBABLE CAUSE
REMEDY
PLATFORM LEVELING SYSTEM.
Automatic leveling inoperative.
(35/n35/n40/45 electric)
Hydraulic system oil low.
Replenish oil as necessary.
Dual check valves dirty/inoperative.
Clean or replace as necessary.
Restricted or broken hydraulic line or fitting on
slave cylinder or main lift cylinder.
Clean, repair, or replace line or fitting.
Worn seal(s) in slave level or main lift cylinder.
Replace seal(s).
Counterbalance valve in slave cylinder defective.
Replace counterbalance valve.
Slave level or main lift cylinder not functioning
properly.
Repair or replace cylinder.
Platform will not maintain level attitude.
Counterbalance valve on slave leveling cylinder
improperly adjusted or not functioning properly.
Replace valve.
Worn seal(s) in slave level or main lift cylinder.
Replace seal(s).
Damaged slave level or main lift cylinder.
Repair or replace cylinder.
No response to platform leveling controls.
Level control switch inoperative.
Repair or replace control switch lever.
Run systems test
Hydraulic system oil low.
Replenish oil as necessary.
System orifice plugged/dirty.
Clean orifice.
Restricted or broken hydraulic line or fitting.
Clean, repair, or replace line or fitting.
Control valve not functioning properly.
Repair or replace valve.
No electric to control valve.
See proper wiring diagram. Run systems test
Slave cylinder not functioning properly.
Repair or replace pump.
Main proportional valve in-operative
Run systems test
Incorrect personality settings
check settings
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