Step-by-step fault isolation for CIPR-series generators to help technicians identify issues quickly, apply the right fix, and minimize downtime.
Description:
This CIPR Generator Trouble Tree is designed to guide service teams through the most common generator faults using logic-based troubleshooting tied to system alarms, start-up behavior, and component-level symptoms. Whether it's a fuel, electrical, or sensor issue, this tree helps pinpoint root causes—reducing trial-and-error, cutting time on site, and ensuring fast resolution. Use it during startup, field repairs, or preventive maintenance to stay productive and avoid unnecessary part replacements.
| Issue | Cause | Fix | Additional Notes |
|
Low Voltage/ Hz Alarm
|
Poor fuel pressure / supply | Adjust fuel pressure to 10-14 in-Wc |
In some cases this alarm is
active because the controller senses low voltage upon an unscheduled shutdown and is not the actual cause for the shutdown. |
| Over-loading | Decrease load on generator | ||
| Unbalanced load | Balance load on generator | ||
| Loss of voltage sensing | Re-terminate voltage sensing wires in top of MCB | ||
| ECM DTC resulting in engine shutdown | Connect to ECM for diagnostics | ||
| Wrong fuel setting | Turn switch to proper fuel setting | ||
|
Low Oil Pressure Alarm
|
Oil pressure is below operating range | Further diagnostics |
In some cases this alarm is
active because the controller senses low oil pressure upon an unscheduled shutdown and is not the actual cause for the shutdown. |
| Poor fuel pressure / supply | Adjust fuel pressure to 10-14 in-Wc | ||
| Broken throttle body gear (high hour units) | Remove and rotate gear or replace | ||
|
Low Oil Level Alarm
|
Oil level is below green line on Lm500 | Add oil |
This alarm is activated by the controller if the oil level in the Lm500 Murphy is below the green line in the sightglass.
|
| Lm500 is faulty | Diagnose, replace Lm500 | ||
|
Communication failure
|
ECM fuse is blown | Diagnose cause before replacing fuse |
Communication is lost between the controller and the engines ECM.
|
| CAN BUS connection is broken | Inspect CAN BUS circuit and VIC connector | ||
|
No crank
|
Faulty wiring from controller | Inspect and repair wiring |
If the engine will not crank it is mostlikely an electrical issue
|
| Faulty wiring on engine harness | Inspect and repair wiring | ||
| Low battery voltage | Charge or replace battery | ||
|
No Start
|
Poor fuel pressure or supply | Adjust fuel pressure or supply to proper specifications |
There are many reasons an engine will not start.
Follow diagnostics procedures before replacing parts |
| Faulty fuel solenoid | Replace fuel solenoid | ||
| No or poor spark | Replace Spark plugs or coils/distributor | ||
| Too much intake restriction | Replace air filter | ||
|
High Coolant temp
|
Poor coolant quality | Flush coolant |
The engines ECM will cause a shutdown if the coolant temperature exceeds the allowed limit. This may not be displayed as a coolant level shut down on the generator's controller
|
| Low coolant | Add coolant | ||
| Fan belt is worn or broken | Replace fan belt | ||
| Electric fan isnt turning on (CIPR-15Z) | Review rows below | ||
|
Electric fan is not turning on (CIPR-15Z)
|
Faulty coolant temp sensor | Replace sensor |
Follow diagnostics procedures before
replacing parts |
| Faulty fan relay | Replace Fan relay | ||
| Faulty wiring | Repair Wiring |