P0234-TURBOCHARGER OVERBOOST CONDITION

For a complete wiring diagram Refer to Section 8W

When Monitored:
With the engine running and the ECM attempting to govern turbocharger boost pressure.
Set Condition:
The Intake Air Temperature/Boost Pressure Sensor indicates actual turbocharger boost is greater than the ECM setpoint for 6.5 seconds.

Possible Causes

INTERMITTENT DTC

INTAKE AIR RESTRICTION

INTAKE AIR LEAK

VACUUM HOSES/TUBES

BOOST PRESSURE ACTUATOR

TURBOCHARGER

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

1.CHECK FOR ACTIVE DTC

Is the status Active for this DTC?

Yes

Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

2.CHECK FOR INTAKE AND EXHAUST SYSTEM RESTRICTIONS

NOTE: Damaged, restricted or poorly connected intake and turbocharger related tubes can cause this DTC to set.

Were any problems found?

Yes

Repair or replace as necessary.
Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

3.INTAKE AIR TEMPERATURE/BOOST PRESSURE SENSOR CIRCUIT RESISTANCE

Is the resistance below 10.0 ohms for each measurement?

Yes

Repair the Boost Pressure Sensor circuit(s) that measure above 10.0 ohms for an open.
Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

4.CHECK THE BOOST PRESSURE SYSTEM

View repair.

Yes

Repair as necessary.
Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)