Cummins/Onan M1895s troubleshooting: 8 fault codes and symptom-cause-remedy entries from the manufacturer's own service documentation.
Cummins/Onan M1895s — full specs, parts & maintenance.
All Cummins/Onan fault codes →
| Symptom | Remedy |
|---|---|
| The engine does not crank. | Service the battery and battery terminals and cables. See Maintenance. Replace the control circuit fuse (above the flywheel housing in a twist-lock holder) if it has blown. |
| The engine cranks, but does not start. | Check the fuel supply. If a fault circuit breaker has tripped, service the fault, and reset the circuit breaker. Service the battery if the engine cranks too slowly to start, refill with engine oil of suitable viscosity and plug in or service the engine coolant heater, if provided. Install an engine coolant heater if necessary. See Maintenance. |
| The engine coolant temperature gauge indicates 2200F or more while the engine is running. | Shut down the set if possible. See Maintenance for servicing the cooling system. Disconnect as many non-critical loads as possible so that the engine will run cooler, and service as soon as possible. |
| The engine shuts down due to high engine temperature or low coolant level. | Shut down the set if possible. See Maintenance for servicing the cooling system. Disconnect as many non-critical loads as possible so that the engine will run cooler, and service as soon as possible. |
| The engine oil pressure gauge indicates less than 20 psi. | Shut down the set if possible. Fill oil, if necessary. Disconnect as many non-critical loads as possible so that the engine will run cooler, and service as soon as possible. |
| The engine shuts down due to low oil pressure or low oil level. | Shut down the set if possible. Fill oil, if necessary. Disconnect as many non-critical loads as possible so that the engine will run cooler, and service as soon as possible. |
| The engine shuts down due to over-speed. | Check the governor-throttle linkage. See Adjustments. Reset the tripped fault circuit breaker. |
| There is no output because the line circuit breaker (if provided) or the field circuit breaker has tripped. | Determine the cause (overload or short circuit) and clear the fault. Reset the line circuit breaker. Reset the field circuit breaker. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.