JLG 25RTS Service & Maintenance page 68

SECTION 3 - TROUBLESHOOTING
TROUBLE
No response to control
Machine drives erratically
Machine will not travel forward
Machine will not travel in reverse
High speed function does not operate
3-4
Table 3-2. Chassis Troubleshooting
PROBABLE CAUSE
DRIVE SYSTEM
Enable switch not activated
Function not activated within the 3 seconds after
enable switch was depressed
Enable switch not functioning properly
Hydraulic system oil low
Drive hubs disengaged
Controller not properly adjusted
Hydraulic pump not functioning properly
Restricted or broken pump supply line
Restricted or broken line on valve bank
Drive motor(s) not functioning properly
Damaged wiring on controller
Controller not functioning properly
Drive brake not releasing
Microswitch on controller improperly adjusted
Enable switch not activated
Function not activated within the 3 seconds after
enable switch was depressed
Enable switch not functioning properly
Hydraulic system oil low
Restricted or broken hydraulic line or fitting
Controller not adjusted properly
Control valve not functioning properly
Drive motor(s) not functioning properly
Defective controller
See: Machine will not travel forward
Loose or damaged wiring between controller and
high speed switch
Defective high speed control switch
Loose or damaged wire in control box wire har-
ness
– JLG Sizzor –
REMEDY
Activate enable switch
Reactivate enable switch
Replace enable switch circuit card
Replenish oil as necessary
Engage hubs
Correctly adjust controller
Repair or replace pump
Clean, repair or replace line
Clean, repair or replace line
Repair or replace motor(s)
Repair or replace wiring
Repair or replace controller
Determine cause and repair or replace brake
Adjust microswitch on controller for proper opera-
tion
Activate enable switch
Reactivate enable switch
Replace enable switch circuit card
Replenish oil as necessary
Clean, repair or replace line or fitting
Correctly adjust controller
Repair or replace valve
Repair or replace motor(s)
Repair or replace controller
Ensure proper connection of wires. Using suitable
test meter, perform continuity test on wiring
between controller and switches. Repair or
replace wires as necessary.
Replace switch
Ensure proper connection of wire at the control
switch. Using suitable test meter, perform continu-
ity test on wire. repair or replace harness as neces-
sary.
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