Most Common Diesel Injector Fault Codes

Fault Code	Meaning	Likely Cause
P0201–P0208	Injector Circuit Malfunction (Cylinder-specific)	Wiring issue, faulty injector, ECU problem
P2146 / P2149	Injector Group Supply Voltage/Open Circuit	Common in Cummins engines; failed injector driver circuit
P030X (e.g., P0302)	Cylinder Misfire Detected	Faulty injector, compression loss, spark issue (gas & diesel overlap)
P0263–P0269	Cylinder Contribution/Balance Faults	Uneven injector performance, mechanical engine issue
P1211 (Ford Powerstroke)	ICP Pressure Above/Below Desired	Injector control pressure problem
P0093	Fuel System Leak – Large	High-pressure leak, split injector body, rail sensor fault
P0087	Fuel Rail/System Pressure Too Low	Clogged injector, failing fuel pump