Onan generator · 7 model lines
Onan generator code 3: Service Check
Onan documentation for 7 model lines lists 3 as “Service Check”.
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 3 means by model
What you can safely check
- Use the operator manual fault-code display process to identify the second-level two-digit code.
- Do not continue restarting until the second-level code is recorded.
- Press Stop once to read the two-digit second-level blink code if the manual procedure is available.
- Record both blink sequences before calling service.
- Record the two-digit code before calling service.
- Record the full blink sequence and stop using the generator if the fault repeats.
Stop and call a technician for
- Internal generator electrical output, inverter, controller, sensors, fuel system, ignition, AC circuit, and engine 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 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 981-0169OnanCummins Onan QG 2800/2800 EVAP KV Spec E-M Operator Manual 981-0153