PACCAR MX (2004 Emissions) Fault Code: P222C Internal ECU Ambient Pressure – Internal Error

SET CONDITIONS:
The PCI ECU (D420) detects that the internal ambient pressure sensor is faulty.

DIAGNOSTIC CONDITION:
This diagnostic runs continuously when the ignition is on.

CORRESPONDING OBD READINESS MONITOR:
None

RESET CONDITION:
This DTC changes to inactive when the fault is no longer detected.

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:
Faulty pressure sensor, internally in ECU

ADDITIONAL INFORMATION:
The PCI ECU has an internal ambient pressure sensor in the housing. The ambient pressure sensor is not serviceable.