Cummins/Onan Not Specified troubleshooting: 22 fault codes and symptom-cause-remedy entries from the manufacturer's own service documentation.
Cummins/Onan Not Specified — full specs, parts & maintenance.
All Cummins/Onan fault codes →
| Code | Meaning | Remedy |
|---|---|---|
| 21 | Starter Solenoid Circuit - controller senses a short circuit | - Check Connections at starter motor - Shorts and/or grounds at solenoid |
| 22 | Governor Actuator Overload - duration of operation at or near full-duty cycle is beyond the design limit | - Check Load - Air intake restriction - Exhaust restriction - Air leak in fuel system |
| 23 | Low Oil Pressure Cutoff Switch | |
| 24 | Temperature Sending Unit | |
| 27 | AC Output Sense Fault | |
| 28 | Quadrature Sense Fault | |
| 29 | High Battery Voltage | |
| 35 | Control Card | |
| 36 | Engine Stopped Fault | |
| 37 | Invalid Genset Configuration | |
| 38 | Field Overload | |
| 45 | Speed Sense Fault | |
| 23 | Low Oil Pressure Cutoff Switch fault | -Check -Perform fuel flow test -Governor linkage for binding -High idle adjustment -Injectors -Injection pump timing -Compression |
| 24 | Temperature Sending Unit fault | -Check -Connections in wiring harness -Switch continunity |
| 35 | Control Card fault | -Check -Control |
| 45 | Speed Sense Fault−controller does not sense quadrature frequency and voltage | -Check -F2 Fuse -Starter circuits -K2 relay and connections -Rotor/stator windings for opens/shorts/ grounds |
| 010 | External Coolant Loss | -Visually check for: -Coolant level is OK -Cracked or leaking hoses -Loose clamps -Leaks or defects in radiator -Coolant in oil |
| 47 | Excessive White Exhaust Smoke at Start-up (Warm Engine) | -Check: -Glow plug operation -Low engine operating temperature -Valve settings -Air leaks in fuel system |
| 48 | Excessive White Exhaust Smoke at Start-up (Cold Engine) | -Check: -Glow plug operation -Air leak in fuel system -Valve settings |
| Engine Cranks but will not Start | Engine Cranks but will not Start |
| Symptom | Cause | Remedy |
|---|---|---|
| Engine does not start | Check battery voltage, remote starting system, and electric starting system. | |
| Engine losing speed momentarily or low engine power | Dirty cooling surfaces, operating without the engine air housing, poor air circulation, improper lubrication, wrong injection timing and engine overload. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Documented causes: Dirty cooling surfaces, operating without the engine air housing, poor air circulation, improper lubrication, wrong injection timing and engine overload.. See the table for the matching fixes.