The PowerCommand 1.2 is a generator-set controller. It is used on generator sets from Cummins/Onan, including the 90 D5, C150 D2R, C200 D2R and C90 D5.
| Symptom | Cause | Remedy |
|---|---|---|
| Coolant Temperature Above Normal | Low Coolant Level | Add coolant. |
| Coolant Temperature Above Normal (Marine) | Low Coolant Level | Add coolant. |
| Coolant Temperature Below Normal | Radiator Shutters Stuck in Open Position or Opening Early | Inspect the shutters. Repair or replace if necessary. |
| Engine Cranks But Will Not Start (No Smoke From Exhaust) | No Fuel In Tank | Add fuel. |
| Engine Hard to Start or Will Not Start (Exhaust Smoke Present) | Engine Cranking Speed Low (Below 150 RPM) | Check engine starting system. |
| Engine Power Output Low | Excessive Load for Engine Horsepower Rating | Reduce vehicle load. |
| Engine Starts But Will Not Keep Running | Air In The Fuel System | Check for air in fuel, tighten fuel connections, tighten filter, check fuel tank stand pipe. |
| Engine Will Not Crank or Cranks Slowly (Air Starter) | Incorrect Oil For Operating Conditions | Change oil and filters. Use recommended type (15W-40). |
| Engine Will Not Crank or Cranks Slowly (Electric Starter) | Incorrect Oil | Change oil and filters. Use recommended type (15W-40). |
| Engine Will Not Reach Rated Speed When Loaded | Excessive Load for Engine Horsepower Rating | Reduce vehicle load or use lower gear. |
| Engine Will Not Shut Off | Fuel Pump Manual Override Open. Refer to page 10-3. | Check to make sure manual override screw is out to maximum travel. |
| Exhaust Smoke Excessive Under Load | Intake Air System Restricted | Check intake air system for restrictions. |
| Lubricating Oil Pressure Low | Incorrect Oil Level | Check for oil leaks. Add or drain engine oil. Check dipstick calibration. |
| White Smoke or Rough Running At Idle (After Warmup Period) | Low Coolant Temperature | Refer to "Coolant Temperature Below Normal" chart. |
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.