PACCAR MX (2004 Emissions) Fault Code: P0563 PCI ECU Power Supply – Data Valid but Too High on ECU (D420) Pin (B60) or Pin (B61) or Pin (B62)

SET CONDITIONS:
The ECU power supply voltage is too high.

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:
Check the power supply level.

ADDITIONAL INFORMATION:
Numerous diagnostics will not run anymore.