Cummins Onan P4500i error codes
2 codes from the official Cummins manual (P4500i), each with the manual page.
Applies to: Cummins Onan P4500i.
| Code | What it means | What to do | Service | Manual |
|---|---|---|---|---|
| LOW OIL LED Low oil | Low engine oil level stopped the generator. The low oil LED indicates this condition. | If the low oil LED is illuminated, turn the battery switch to OFF. Add engine oil. Check the engine oil level if the engine starts and then shuts down. | owner | p. 25 |
| OVERLOAD LED Overload | Generator is overloaded. With the OVERLOAD LED on and the OUTPUT READY LED off, there is no power at the AC receptacles. The generator may also run rough or bog when a load is applied. | Check the AC load and unplug some devices. Check the air inlet. Stop and restart the engine. If an AC circuit breaker has tripped, check the AC loads and reset the breaker. Replace or repair any faulty tool or appliance, then stop and restart the engine. | owner | p. 25 |
Source: official Cummins manual, read 2026-11-01. "Owner" means the manual lists steps you can take; "dealer" means it directs you to authorized service. Fuel, gas and electrical work on generators is for qualified technicians; follow the manual's safety section.