Onan generator · 5 model lines
Onan generator code 2: Low Oil Pressure
Onan documentation for 5 model lines lists 2 as “Low Oil Pressure”.
Check your model first. The same code can mean different things on different models. Find the model number on the appliance's data label, then use the matching row below.
What code 2 means by model
What you can safely check
- Turn the generator off and let it cool before any visual owner check.
- Check oil level only as allowed by the operator manual with the generator off and cool.
- Stop the generator and let it cool.
- Check engine oil level only after safe shutdown and according to the operator manual.
- Check oil level only with the unit off and cool.
Stop and call a technician for
- Internal generator electrical, fuel, engine, sensor, controller, and output-voltage diagnosis belongs to Cummins service or a qualified generator technician.
- Electrical output, inverter, controller, stator, rotor, fuel injection, sensors, wiring, coolant-system service, fuel leaks, and generator compartment repairs belong to Cummins service or a qualified generator technician.
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.
Write this down before you call
- generator model/spec letter
- hour meter
- fault blink count
- loads running when the shutdown occurred
Full code tables for these models
Related troubleshooting guides
Official sources
OnanCummins Onan RV Generator ManualsOnanCummins Onan Generator Set for RV Operator Manual A031C171OnanCummins Onan Generator Set for RV Operator Manual A035D009OnanCummins Onan RV Generator Set HGJAA/HGJAB/HGJAC Spec A-E Operator Manual 983-0101OnanCummins Onan Quiet Diesel 10000/12500 HDKCA/HDKCB Operator Manual A043D713OnanCummins Onan Quiet Diesel 5000 HDKBA Operator Manual 0981-0166OnanCummins Onan Quiet Diesel 6000/7500/8000 HDKAH/HDKAJ/HDKAK Operator Manual A046L053OnanCummins Onan QG 2800/2800 EVAP KV Spec E-M Operator Manual 981-0153