JLG 330CRT Service Maintenance Manual page 44

SECTION 3 - TROUBLESHOOTING
.
TROUBLE
No Response to LIft Control
Platform will not raise.
Platform will not lower
Platform raises and lowers erratically
3-2
Table 3-1. Elevation System Troubleshooting
PROBABLE CAUSE
Platform Elevation System
Lift not performed within three seconds after lift
function switch is selected.
Lift control switch inoperative.
Hydraulic system oil low.
Restricted or broken supply line on valve
bank or pump.
Control valve not functioning properly.
Lift cylinder not functioning properly.
Hydraulic pump not functioning properly. Repair or replace pump.
Joystick not activated within three sec-
onds after lift switch is activated.
Load capacity exceeded. (Personnel
and/or equipment on platform).
Hydraulic system oil low.
Restricted or broken hydraulic line or fit-
ting.
Control valve not functioning properly.
Lift cylinder not functioning properly.
Engine does not respond when lift control
switch is moved to up position.
No electrical signal being sent to lift up control valve
cartridge.
Joystick not activated within three sec.
after lift switch is activated.
No electrical signal sent to lift down con-
trol valve cartridge.
Lift down control valve cartridge not functioning
properly.
Lift cylinder not functioning properly.
Engine does not respond when lift switch
is moved to down position.
No electrical signal being sent to lift down
control valve.
Hydraulic system oil low.
Restricted or broken hydraulic line or fit-
ting.
– JLG Lift –
REMEDY
Reselect lift function switch, then activate joystick
within three seconds.
Repair or replace control switch.
Replenish oil as necessary.
Clean, repair or replace line.
Repair or replace valve.
Repair or replace cylinder.
Activate lift switch, then activate joystick
within three seconds.
Reduce load. (Refer to capacity placard).
Replenish oil as necessary.
Clean, repair, or replace line or fitting.
Repair or replace valve.
Repair or replace lift cylinder.
Refer to Electrical System Troubleshoot-
ing - No response to control switch.
Refer to Electrical System Troubleshooting - No
response to control switch.
Depress lift switch, then activate control-
ler within three seconds.
Refer to Electrical System Troubleshoot-
ing - No response to control switch.
Repair or replace lift down control valve
cartridge.
Repair or replace lift cylinder.
Refer to Electrical System Troubleshoot
ing - No response to control switch.
Refer to Electrical System Troubleshoot
ing - No response to control switch.
Replenish oil as necessary.
Clean, repair or replace line.
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