RV Atlas

Onan ยท 19 codes

Cummins Onan QG 4000 / 3600 LP generator fault codes

Every fault code, display message, and status light listed in Onan's manuals and support pages for QG 4000 / 3600 LP KY (Spec J-R); QG 4000 / 3600 LP KYD (Spec A-C). Select a code for what it means, what you can safely check, and when to call a technician.

Confirm your model

Codes are model-specific. Match the model number on the appliance data label to one of these before using the table:

QG 4000/3600 LP KY Spec J-N, QG 4000/3600 LP KY Spec P-R, QG 4000/3600 LP KYD Spec A-C

Where to look and what to record

  • generator model/spec letter
  • hour meter
  • fault blink count
  • loads running when the shutdown occurred

Code table

CodeWhat the manufacturer saysListed for
3Service CheckAll listed models
4Over Crank / OvercrankAll listed models
12Over Voltage / OvervoltageAll listed models
13Under Voltage / UndervoltageAll listed models
14Over Frequency / OverfrequencyAll listed models
15Under Frequency / UnderfrequencyAll listed models
27Voltage SenseAll listed models
29High Battery VoltageAll listed models
32Low Cranking SpeedAll listed models
35Control Card FailureAll listed models
36Engine StoppedAll listed models
37Invalid Generator Set Configuration / Invalid Genset ConfigurationAll listed models
38Over Current (Field Overload) / OvercurrentAll listed models
41Generator RotorAll listed models
42ProcessorAll listed models
43ProcessorAll listed models
45Speed SenseAll listed models
47IgnitionAll listed models
48Generator Field SenseAll listed models

Generators can produce carbon monoxide, hot surfaces, fuel hazards, moving-part hazards, and lethal voltage. Shut the generator down and do not open energized compartments unless qualified.

Troubleshooting guides

Official manuals and support pages

OnanCummins Onan RV Generator ManualsOnanCummins Onan QG 4000/3600 LP KY Spec J-N Operator Manual 981-0159OnanCummins Onan QG 4000/3600 LP KY Spec P-R Operator Manual A041D131OnanCummins Onan QG 4000/3600 LP KYD Spec A-C Operator Manual 981-0169