The DEIF SGC420 is a generator-set controller. It is used on generator sets from Cummins/Onan, including the C44D5R.
| Code | Meaning |
|---|---|
| 27 | Low AC voltage shutdown |
| 51 | High Current warning/shutdown |
| 59 | High AC voltage shutdown |
| 81 o | Over frequency shutdown/warning |
| 81 u | Under frequency shutdown |
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.