PACCAR MX (2004 Emissions) Fault Code: P1222 Injector Solenoid Valve Cylinder 4 – Short Circuit Between ECU (D420) Pin (A11) and Pin (A12)
PACCAR MX (2004 Emissions) Fault Code: P1222 Injector Solenoid Valve Cylinder 4 – Short Circuit Between ECU (D420) Pin (A11) and Pin (A12)
SET CONDITIONS:
The PCI ECU (D420) detects a short circuit between the ECU pin A11 and A12 circuits.
DIAGNOSTIC CONDITION:
This diagnostic runs when the engine is running.
CORRESPONDING OBD READINESS MONITOR:
None
RESET CONDITION:
This DTC changes to inactive when the fault is no longer detected. To enable the injector output, the DTCs must be cleared.
REPAIR VERIFICATION:
1. Clear all DTCs.
2. Test drive or operate the vehicle to meet the diagnostic conditions and set conditions.
3. Did the DTC come back?
– No, repair successful
– Yes, repair unsuccessful
POSSIBLE CAUSES:
1. Faulty injector
2. Engine wiring harness
ADDITIONAL INFORMATION:
The injector output is disabled by the PCI ECU when this DTC is detected. The output stays disabled until the DTC is cleared.
