Generac
®
Power Systems, Inc. 23
Section 5 — Troubleshooting
Guardian 40kW Liquid-cooled Generators
TROUBLESHOOTING POINTS
PROBLEM CAUSE CORRECTION
Engine won’t crank. 1. 15 amp fuse blown. 1. Replace fuse.
2. Loose or corroded or defective 2. Tighten, clean or replace
battery cables. battery cables as necessary.
3. Defective starter contactor. 3. Replace contactor.
4. Defective starter motor. 4. Replace starter motor.
5. Dead or Defective Battery. 5. Remove, change or replace battery.
6. 4 amp fuse blown. 6. Replace fuse.
Engine cranks, but won't start 1. Out of fuel. 1. Replenish fuel.
2. Fuel solenoid (FS) is defective 2. Replace solenoid.
3. Open Wire #14 from Engine Control 3. Reconnect wire.
circuit board.
4. Spark plugs defective. 4. Clean, regap or replace plugs.
Engine starts hard, runs rough. 1. Flame arrestor (air cleaner) plugged or 1. Clean or replace as needed.
damaged.
2. Plugged fuel line. 2. Unclog fuel line.
3. Defective spark plugs. 3. Clean, regap or replace plugs.
Engine starts, then shuts down. 1. Engine oil level is low. 1. Check oil and add oil as needed.
2. Engine is overheated. 2. Check cooling system for leaks.
3. Defective Low Oil Pressure Switch 3. Replace switch.
4. Defective Coolant Temperature Switch 4. Replace switch.
5. Defective Control Module circuit board. 5. Replace board.
6. Coolant Level is Low. 6. Repair leak - Add coolant.
7. Defective Low Coolant Level Switch 7. Replace Switch.
AUTO/OFF/MANUAL Switch at, 1. Defective AUTO/OFF/MANUAL switch 1. Replace switch.
OFF engine continues to run 2. Open/disconnected wire #15A between 2. Reconnect/close wire.
AUTO/OFF/MANUAL switch and Control
Module circuit board.
3. Defective Control Module circuit board 3. Replace board.
No AC output from generator. 1. Check main line circuit breaker. 1. Reset to ON or CLOSED.
2. Check circuit breaker & fuses. 2. Reset and replace, if necessary.
3. Transfer switch set to NORMAL position 3. Set to GENERATOR position.
4. Generator internal failure. 4. Contact an authorized service dealer.
5. Thermal circuit breaker open. 5. Auto-reset - Wait 5 min. and
attempt restart.
NOTE:
Under normal operating conditions, if repair of generator set or replacement of any parts is necessary dur-
ing the warranty period, you must contact an authorized service dealer. Failure to have the repair or replace-
ment performed by the authorized service dealer will result in non-coverage of warranty repair cost.