The Electronic Voltage Regulator is a generator-set controller. It is used on generator sets from Cummins/Onan and Mitsubishi, including the MDG.
Used across brands: Cummins/Onan, Mitsubishi
Also fitted to: Cummins/Onan RBAA Hydraulic Genset (10kW), Cummins/Onan RBAA Hydraulic Genset (15kW), Cummins/Onan RBAA Hydraulic Genset (6kW), Cummins/Onan RBAA Hydraulic Genset (8kW).
| Code | Meaning | Remedy |
|---|---|---|
| F1 | Blown Fuse (F1) | Replace with a 20 amp (yellow) blade-type fuse (Page 29). If the new fuse blows, check for ground faults in harnesses 338-4084, 338-4085 and 338-4087 and replace as necessary (Page 23 or 26). |
| Symptom | Cause | Remedy |
|---|---|---|
| Frequency too high or too low or erratic | Misadjusted frequency | Adjust frequency as necessary (Page 19). |
| No output or air discharge — engine running | ON/OFF Switch OFF | Turn the switch ON. |
| No output — genset running and air discharging | Line circuit breaker (vehicle AC distribution panel) OFF, TRIPPED or faulty | A. If the circuit breaker is OFF, find out why, make sure it is safe to reconnect power, and then switch it ON. b. If the circuit breaker TRIPPED, shut down the genset and repair the shorted or grounded equipment that caused tripping. c. Replace a faulty circuit breaker. |
| Noisy generator | Loose brush block or fan, worn bearing or misaligned rotor and motor | See an authorized Onan dealer. |
| Noisy pump or motor (rattling sound) | Air trapped in hydraulic fluid | Purge the air and refill the oil reservoir as necessary (Page 17). |
| Output voltage too low | Misadjusted frequency | Adjust frequency as necessary (Page 19). |
Fault codes and symptom→remedy steps extracted from this controller’s service/owner documentation; verify against the official manual before servicing. Aggregated from the service documentation of generator sets built on this controller.