P003A

P003A-TURBOCHARGER BOOST CONTROL MODULE POSITION EXCEEDED LEARNING LIMIT





For a complete wiring diagram Refer to Diagrams/Electrical.

Theory of Operation


The variable geometry turbocharger (VGT) is electronically activated by the VGT actuator. The VGT actuator is a smart device and receives information via the J1939 datalink from the ECM. The VGT actuator performs its own diagnostics and reports failures back to the ECM using the J1939 datalink. The ECM then decodes the error message and converts it to a fault code. The ECM lights the MIL lamp immediately after the diagnostic runs and fails. The ECM turns off the MIL lamp after the diagnostic runs and passes in 4 consecutive drive cycles.

- When Monitored:
Ignition on.

- Set Condition:
The VGT actuator reference position was not detected during a learn span, true position is not known.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview


Diagnostic Test


1. OTHER DTC'S
Ignition on, engine not running.
With the scan tool, read DTC's
Is U010C active?

Yes


- Repair U010C first.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test


No


- Go To 2



2. INCORRECT ACTUATOR INSTALLATION
Check vehicle history for previous VGT actuator replacements.
Has the actuator just been replaced?

Yes


- Remove actuator and install in the correct position.


No


- Go To 3



3. VGT ACTUATOR
Turn the ignition off.
Disconnect the VGT actuator harness connector.

NOTE: Check connectors - Clean/repair as necessary.

Remove the VGT actuator from the turbocharger.
Is the VGT actuator drive gear broken/damaged?

Yes


- Replace the VGT actuator.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test


No


- Go To 4
-



4. TURBOCHARGER
Inspect the sector gear on the turbocharger for damage or broken teeth.
Move the sector gear lever on the turbocharger bearing housing up and down from stop to stop.
Check for smooth movement between the stops.

NOTE: The actuator lever must move evenly and crisply as it is moved.

Does the nozzle slide evenly from stop to stop and are the gear teeth undamaged?

Yes


- Replace the VGT actuator
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test


No


- Replace the turbocharger assembly.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test