P0234

DTC P0234: Turbocharger Wastegate System Malfunction

TECHNICAL DESCRIPTION

- The ECM checks that the engine is not overcharged by always monitoring intake air volume.
- The ECM protects the engine by shutting off fuel when an overcharged condition is detected.

DESCRIPTIONS OF MONITOR METHODS

It detects overcharging failure by monitoring intake air volume.

MONITOR EXECUTION

Continuous

MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)

Other Monitor (There is no temporary DTC stored in memory for the item monitored below)

- Turbocharger wastegate solenoid monitor
Sensor (The sensor below is determined to be normal)

- Mass airflow sensor
- Intake air temperature sensor
- Barometric pressure sensor
- Throttle position sensor

DTC SET CONDITIONS

Logic Flow Chart






Check Condition, Judgement Criterion

- Volumetric efficiency is more than 190 - 230 percent for 1 second.

FAIL-SAFE AND BACKUP FUNCTION

- Fuel is cut in abnormal engine overboost condition.

OBD-II DRIVE CYCLE PATTERN

Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 17 Monitors, Trips, Drive Cycles and Readiness Codes.

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)

- Intake charge pressure failed.
- Turbocharger wastegate actuator failed.
- Intake charge pressure control system failed.
- ECM failed.

DIAGNOSIS

Required Special Tool:

- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A

STEP 1. Check the intake charge pressure.

Intake Charge Pressure Check.

Q. Are there any abnormalities?

YES Repair it. Then go to Step 5.
NO Go to Step 2.
STEP 2. Check the intake charge pressure control system.

Testing and Inspection.

Q. Are there any abnormalities?

YES Repair it. Then go to Step 5.
NO Go to Step 3.
STEP 3. Check the turbocharger wastegate actuator.

Testing and Inspection.

Q. Are there any abnormalities?

YES Repair or replace it. Then go to Step 5.
NO Go to Step 4.
STEP 4. Check the trouble symptoms.

(1)Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 17 Monitors, Trips, Drive Cycles and Readiness Codes.

(2)Check the diagnostic trouble code (DTC).

Q. Is DTC P0234 set?

YES Replace the ECM (Refer to, Removal and Installation Removal and Replacement).
Then go to Step 5.
NO It can be assumed that this malfunction is intermittent. How to Cope With Intermittent Malfunctions.
STEP 5. Test the OBD-II drive cycle.

(1)Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 17 Monitors, Trips, Drive Cycles and Readiness Codes.

(2)Check the diagnostic trouble code (DTC).

Q. Is the DTC P0234 set?

YES Retry the troubleshooting.
NO The inspection is complete.