Applicable Systems
EMCP 4.2
Symptoms
The EMCP 4.2 controller reports a programmed parameter fault. The system voltage on the parameter circuit is above normal or shorted to a high voltage source. The generator set may not start or may shut down depending on the affected parameter.
Possible Causes
- Parameter programming error or corruption
- Wiring short between parameter circuit and power source
- ECM internal fault affecting parameter memory
- External voltage surge damaging parameter circuit
Troubleshooting Steps
- Step 1: Navigate to EMCP DIAGNOSTICS menu and read active fault codes
Fault code 268-3 displayed as active with timestamp - Step 2: Check parameter settings using Cat ET (Electronic Technician)
All parameters match factory default values - Step 3: Inspect wiring harness between ECM and parameter sensors for shorts
No continuity to power source when unplugged at ECM - Step 4: Re-flash ECM with latest parameter file if values are corrupted
Parameters successfully written and verified
How to Reset
To reset: 1) Correct the parameter fault. 2) Press FAULT RESET on EMCP. 3) Press AUTO. Caution: Never reset without verifying all parameters are correct.
Frequently Asked Questions
- Q: What does CID 268 represent on Cat EMCP 4.2?
CID 268 is the Programmed Parameter Fault identifier. It indicates a problem with the programmable parameters stored in the ECM.
- Q: Can I continue running the generator with fault 268-3 active?
It depends on the specific parameter affected. Some parameters are non-critical, but voltage-related parameters (FMI 3) should be investigated immediately as they may indicate a short circuit.
Source: Caterpillar EMCP 4.2 Operation & Maintenance Manual (LERMPMM), caterpillarfaultcodes.com CID-FMI Reference
Category: Generator