PACCAR MX (2004 Emissions) Fault Code: P0121 Accelerator Pedal – Sticking Pedal

PACCAR MX (2004 Emissions) Fault Code: P0121 Accelerator Pedal – Sticking Pedal

SET CONDITIONS:
The PCI ECU (D420) detects that both the accelerator pedal and foot brake pedal are depressed for greater than 10 seconds.

DIAGNOSTIC CONDITION:
This diagnostic runs continuously after ignition is keyed 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:
1. Malfunction on the accelerator pedal
2. Malfunction on the brake pedal
3. Driver operating fault

ADDITIONAL INFORMATION:
For this diagnostic, the foot brake pedal signal (CAN message from brake system) is used to determine if the accelerator pedal (F836) is sticking.