PACCAR MX (2004 Emissions) Fault Code: P0650 Malfunction Indicator Lamp (MIl) – Current Too Low or Open Circuit on ECU (D420) Pin (B23)

SET CONDITIONS:
The PCI ECU (D420) detects an open circuit on the control circuit for activation of the MIL.

DIAGNOSTIC CONDITION:
The diagnostic runs continuously when the ignition is keyed on and only when the MIL is not activated.

CORRESPONDING OBD READINESS MONITOR:
None

RESET CONDITION:
The DTC changes to inactive after the diagnostic runs and passes.

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? (Can be pending, inactive or active)
– No, repair successful
– Yes, repair unsuccessful

POSSIBLE CAUSES:
1. Wiring issue
2. Malfunction MIL lamp