Onan 4 fault code — Generator
Applies to: Quiet Diesel 10000 HDKCA, Quiet Diesel 12500 HDKCB
What 4 means
The Cummins Onan Quiet Diesel 10000/12500 HDKCA/HDKCB operator manual lists Code 4 as Over Crank.
Owner-safe checks
- Stop repeated start attempts.
- Check fuel level and obvious exterior air-filter blockage only if safe.
Service-only work
- 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.
Safety boundary
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.
Official sources
- Cummins Onan RV Generator Manuals
- Cummins Onan Quiet Diesel 10000/12500 HDKCA/HDKCB Operator Manual A043D713