JLG M450 ANSI Service Manual - Manual (Page 224)

SECTION 7 - BASIC TROUBLESHOOTING, ELECTRICAL INFORMATION, & SCHEMATICS
7-10 – JLG Lift – 3121127
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Table 7-4. Chassis Assembly - Troubleshooting
TROUBLE PROBABLE CAUSE REMEDY
GENERATOR.
Engine will not start.
Enable switch is open. Actuate switch.
Fuses open. Determine and correct cause; replace fuse.
Ground EMS is open. Pull out EMS to activate.
Defective starter motor. Replace starter motor.
Damaged wiring in ignition circuit (broken wire
on starter). Repair, replace wiring.
Manual start switch not functioning properly. Replace switch/check wiring.
Ignition relay not functioning properly. Replace relay.
Ignition circuit shorted to ground. See proper wiring diagram.
Battery cable(s) not making contact. Clean and tighten cable(s).
Engine will not start (ignition OK).
No fuel. Replenish fuel as necessary.
Clogged fuel filter. Replace fuel filter.
Choke solenoid malfunction. Replace choke solenoid.
Restricted or broken fuel line. Clean or replace fuel line.
Fuel shut-off valve in carburetor stuck or frozen. Repair or replace fuel shut-off. Check for electri-
cal power.
Battery discharged. Charge battery, replace if defective.
Cam timing belt jumped time or broken. Repair or replace timing belt.
Ignition timing slipped. Repair timing.
Engine surges.
Governor not adjusted properly. Correctly adjust governor.
Strong fuel odor.
Fuel tank overfilled. Check fuel tank and immediately wipe up spilled
fuel.
Fuel tank damaged. Drain all fuel from tank and remove tank for
replacement or repair.
Fuel line from tank damaged. Replace fuel line.
Carburetor flooding. Repair, replace or adjust carburetor.