Service manual

9-2013 9. Troubleshooting
2. Inspect the battery connections and cables for cleanliness, tightness, and damage: clean,
tighten, and repair connections and cables as necessary.
3. Check electrolyte level and hydrometer reading in maintenance type batteries: replace
electrolyte and recharge or replace the battery as necessary.
4. Disconnect the generator set control J1 connector. Verify that the J1 pins are fully inserted
and inspect pin condition, using one of the processes listed below. Then insert, repair, or
replace pins as necessary.
Pin Inspection Processes (use one of the following to inspect the pins):
• Use the test points of the tester tool #420-0603
• Use a mating pin connector
• Use a pin gauge the same size (.045") as the mating control connector pin
• Use any suitable device that will not damage the inside contact wipers of the pin
socket
5. Reconnect the J1 connector and test run the generator set for fault occurrence: repair or
replace pins in the connector as necessary.
6. Measure battery voltage at the generator set while attempting to start from a local or
remote switch: recharge or replace the battery if voltage drops below 8 VDC, test and
service the generator set battery charger if so equipped, increase the battery cable size or
run parallel cables.
7. Verify the condition of the spark plugs and whether they are Cummins Onan branded
plugs. Non-resistive type plugs sold through non-Cummins Onan channels can cause this
condition. Replace the spark plug(s) if questionable or of non-Cummins Onan origin.
8. Measure battery voltage and check for voltage increase while the generator set is running.
9.9 No AC Power - Generator Set Running, Status LED
On Steady or Flashing Rapidly
Logic: Circuit Breakers have tripped due to overload or short.
Possible Causes: Circuit breakers, customer loads
Diagnosis and Repair:
1. Status light on - Measure AC output at generator set circuit breaker: reset or turn on the
generator set circuit breaker; diagnose faulty loads as necessary.
9.10 Generator Set Cranks But Does Not Start - No Fault
Code
Logic: Fault codes are based on time lapse between events
Possible Causes: Faulty or incorrect spark plugs, low battery output, low fuel pressure
Diagnosis and Repair:
1. Check and record last fault code.
2. Measure battery voltage at the battery and the generator set.
A030A239 (Issue 10) 89