JLG 150HAX Service Manual - Manual (Page 130)

SECTION 6 - SCHEMATICS
6-2 – JLG Lift – 3120817
Table 6-1.Platform Assembly - Troubleshooting
TROUBLE PROBABLE CAUSE REMEDY
PLATFORM LEVELING SYSTEMS
Platform will not maintain level attitude.
Hydraulic system oil low. Replenish oil as necessary.
Dual pilot check valves dirty/ inoperative. Clean or replace as necessary.
Restricted or broken hydraulic line or fitting on
slave cylinder or master leveling cylinder. Clean, repair, or replace line or fitting.
Spit valve(s) leaking. Clean, repair, or replace spit valve(s).
Worn seal(s) in slave level or master leveling cyl-
inder. Replace seal(s).
Slave level or master leveling cylinder not func-
tioning properly. Repair or replace cylinder.
Counterbalance valve on slave
leveling cylinder improperly adjusted or not func-
tioning properly. Adjust or replace valve.
No response to platform leveling controls.
Circuit breaker open. Determine and correct cause.
Reset circuit breaker.
Hydraulic system oil low. Replenish oil as necessary.
Damaged wiring on control switch or solenoid
valve. Repair or replace wiring.
Control switch not functioning properly. Replace switch.
Restricted or broken hydraulic line or
fitting. Clean, repair, or replace line or fitting.
Control valve not functioning properly. Repair or replace valve.
Slave cylinder not functioning properly. Repair or replace cylinder.
Platform will not adjust “up” to level.
Damaged wiring on control switch or solenoid
valve. Repair or replace wiring.
Restricted or broken hydraulic line or
fitting. Clean, repair, or replace line or fitting.
Slave cylinder not functioning properly. Repair or replace cylinder.
Platform will not adjust “down” to level.
See: Platform will not adjust “up” to level.