Cummins/Onan DQBB troubleshooting: 9 fault codes and symptom-cause-remedy entries from the manufacturer's own service documentation.
Cummins/Onan DQBB — full specs, parts & maintenance.
All Cummins/Onan fault codes →
| Code | Meaning | Cause | Remedy |
|---|---|---|---|
| 231 | Warning lamp lights. | Indicates battery voltage exceeds 32 VDC. Contact an authorized service center. | |
| 250 | Shutdown lamp lights. | Indicates PCC memory error. Data corruption of critical operating parameters. Contact an authorized service center. | |
| 102 | Engine shuts down and will not crank. | Indicates local or remote Emergency Stop. | To reset the local Emergency Stop button : Pull the button out or turn the switch clockwise (button with arrow) and allow it to pop out. Move the Run/Off/Auto switch to Off. Press the Reset switch. Select Run or Auto, as required. |
| Symptom | Cause | Remedy |
|---|---|---|
| Engine starts from generator control panel but will not start automatically or from a remote panel. | (Note: The Run/Off/Auto switch must be in the Auto position for automatic or remote starting). Check the control wiring between the remote switch and the PCC. Contact an authorized service center. | |
| No AC output voltage. | Contact an authorized service center. | |
| Control does not power up when the Run/Off/Auto switch is set to Run or the Self Test switch is pressed. | There is no DC power to the control. | A. Check for battery disconnected, discharged, or improperly connected. b. Fuse F1 (20A/32V, Type 3AG) may be open. Replace with the same type. (Fuse is mounted near engine starter/solenoid, see Figure 4-2). Contact an authorized service center. |
| Warning, Shutdown, and Non-Automatic lamps are not lit. Digital display shows main menu or selected menu. | Indicates all engine systems are normal. No corrective action required | |
| Non-Automatic lamp flashes. | Indicates Run/Off/Auto switch is not in the Auto position. This will prevent automatic starting if an automatic transfer switch is used. | Move the Run/Off/Auto switch to the Auto position for automatic operation. |
| Engine continues to operate at reduced RPM. | Indicates that the engine is operating in idle mode. When the set is operating in the RUN mode, grounding the engine idle input causes generator build-up to be inhibited and the engine to be governed at 800 RPM. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Documented causes: (Note: The Run/Off/Auto switch must be in the Auto position for automatic or remote starting). Check the control wiring between the remote switch and the PCC. Contact an authorized service center.. See the table for the matching fixes.
Documented causes: There is no DC power to the control.. See the table for the matching fixes.
Documented causes: Indicates all engine systems are normal. No corrective action required. See the table for the matching fixes.