The Electronic Voltage Regulator is a generator-set controller. It is used on generator sets from Cummins/Onan and Northern Lights, including the M844DW3G.
Used across brands: Cummins/Onan, Northern Lights
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 |
|---|---|---|
| 12 VDC not available | Check for 12 VDC at terminal 2 of the ON/OFF Switch (S1 on the Wiring Schematic, Page 29). Service as necessary. | |
| Disengaged PTO | Engage the PTO. | |
| Faulty Lead Harness | Check for bent, corroded or missing connector pins and damaged leads in harnesses 338-4084, 338-4085 and 338-4086 and replace as necessary (Page 23 or 26). | |
| Faulty ON/OFF Switch | Turn ON the ON/OFF switch (S1) and check for 12 VDC at switch terminal 1 (Wiring Schematic, Page 29). Service as necessary. | |
| Faulty generator or AVR | See an authorized Onan dealer. | |
| Hydraulic fluid leak | Check for and repair any leaks in the system and refill as necessary (Page 9). | |
| 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. | |
| Loose brush block or fan, worn bearing or misaligned rotor and motor | See an authorized Onan dealer. | |
| Misadjusted frequency | Adjust frequency as necessary (Page 19). | |
| Misconnected Genset Power Supply Cord | Reconnect the genset power supply cord correctly at the vehicle AC distribution panel (Wiring Schematic, Page 29). | |
| NOISY PUMP OR MOTOR (RATTLING SOUND) | Air trapped in hydraulic fluid | Purge the air and refill the oil reservoir as necessary (Page 17). Continuing to run or load a noisy pump or motor can destroy it. Purge the air before continuing. |
| ON/OFF Switch OFF | Turn the switch ON. | |
| Pump speed too high or too low | Verify that the combination of PTO speed ratio and engine speed range results in pump speeds that fall within the specified range. See Specifications. If pump speed falls outside the range, reinstall the PTO with a gear ratio that will keep pump speed within the specified range at all engine speeds. |
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.