The UR 15 is a generator-set controller. It is used on generator sets from Cummins/Onan, including the 75.0 ENT and lsg-875.
| Symptom | Remedy |
|---|---|
| Engine runs, shuts down and cranks for 75 seconds. Cranking cycle stops; fault lamp lights. | Check fuel supply. Check ignition system. |
| Engine runs, shuts down, cranks for 75 seconds, cranking cycle stops, overcrank light ON. | Check fuel supply, check ignition. |
| Engine stops cranking and fault lamp lights, after cranking approximately 75 seconds. | See engine service manual for troubleshooting fuel system, ignition system, etc. After correcting problem, reset engine monitor relay by placing Run-Stop/Reset-Remote switch to Stop/Reset, then back to the required running position. |
| Fault lamp lights and engine shuts down after running for a period. | A. Oil level. Engine will shut down if sensor is closed. b. Check engine manual for troubleshooting oil system. c. High engine temperature. Check coolant level; check water flow (city water cooled systems); check radiator for free air flow, and fan belts for tightness. See engine manual for troubleshooting cooling system. d. Check for faulty oil pressure sensor or faulty high engine temperature sensor. |
| Fault lamp lights immediately after engine starts. | Check for: Overspeed condition as engine starts. |
| Fault lamp lights, no fault exists. | To check a no-fault condition, disconnect leads from TB11 terminals 29, 30 and 31. If fault lamp lights with leads disconnected, replace engine monitor board. Reconnect leads. |
| High engine temperature shutdown. | A. Coolant level. Replenish if necessary. b. City water cooled set |
| Low oil pressure shutdown. | A. Oil level. Replenish if necessary. b. Sensor. Faulty sensor will shut down engine. c. Refer to engine service manual for troubleshooting guide for oil system. |
| Overcrank fault lamp lights and engine stops cranking after approximately 75 seconds. | See engine service manual for troubleshooting fuel system, ignition system, etc. After correcting fault, reset engine monitor relay by placing Run-Stop/Reset-Remote switch to Stop/Reset position, depressing Reset button, then to the required running position. |
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.