JLG 120HX ANSI Service Manual User Manual
Page 103
SECTION 3 - TROUBLESHOOTING
3120686
– JLG Lift –
3-21
INSTRUMENTS AND INDICATORS.
Travel warning horn inoperative.
Circuit breaker open.
Determine and correct cause; reset circuit
breaker.
Damaged wiring in horn circuit.
Repair or replace wiring.
Damaged horn.
Replace horn.
Hourmeter inoperative.
Damaged wiring in hourmeter circuit.
Repair or replace wiring.
Defective pressure switch.
Replace pressure switch.
Inoperative hourmeter.
Replace hourmeter.
Tilt alarm circuit.
Damaged wiring in tilt alarm circuit.
Repair or replace wiring. See proper wiring dia-
gram.
Tilt alarm inoperative.
Replace tilt alarm.
Tilt alarm not adjusted properly.
Adjust tilt alarm.
Defective bulb in tilt light.
Replace bulb.
High engine speed will not function.
Boom above horizontal.
Lower boom.
Horizontal limit switch malfunctioning.
Repair or replace limit switch.
Drive controller defective.
Replace controller.
High engine solenoid malfunctioning.
Repair or replace solenoid valve.
Drive pressure switch malfunctioning.
Replace pressure switch.
Electrical malfunction.
See wiring diagram.
Defective engine governor.
Repair or replace governor.
Function speed control will not function.
Boom above horizontal.
Lower boom.
Horizontal limit switch malfunctioning.
Repair or replace limit switch.
Defective pump section.
Repair or replace pump section.
Electrical malfunction.
See correct wiring diagram.
Table 3-6.Electrical System - Troubleshooting
TROUBLE
PROBABLE CAUSE
REMEDY