PACCAR MX (2004 Emissions) Fault Code: P0046 VGT Turbocharger Actuator – Position Error or Internal Error

PACCAR MX (2004 Emissions) Fault Code: P0046 VGT Turbocharger Actuator – Position Error or Internal Error

SET CONDITIONS:
The VTG turbocharger actuator (L037) detects that:
1. The actuator reference point is not detected or
2. The end stops are out of range or
3. An internal actuator failure is present.

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

CORRESPONDING OBD READINESS MONITOR:
None

RESET CONDITION:
This DTC will change to inactive after the ignition is keyed off and on again and 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?
– No, repair successful
– Yes, repair unsuccessful

POSSIBLE CAUSES:
Actuator failures:
1. Actuator incorrectly calibrated (not calibrated) after installing actuator on turbocharger
2. Internal actuator defects

Temporary blockage of the VTG turbocharger mechanism:
1. Frozen actuator / nozzle ring assembly
2. Soot build-up on the turbocharger nozzle ring mechanism

Permanent blockage of the VTG turbocharger mechanism:
1. Damaged VTG turbocharger nozzle ring
2. Damaged VTG turbocharger sector gear

ADDITIONAL INFORMATION:
1. The position of the VTG turbocharger nozzle ring is monitored by the actuator.

2. The position of the actuator is monitored with an internal sensor and a reference magnet (reference point).

3. After the ignition is keyed on, a learn sweep is performed by the actuator. During this sweep the VTG turbocharger nozzle ring is fully opened and fully closed to check the end positions.

4. The actuator motor is switched off when this fault is active.