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. OBD-II Drive Cycle

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

STEP 1. Check the intake charge pressure.

Refer to On-vehicle Service - Intake Charge Pressure Check. Intake Charge Pressure Check

Q: Are there any abnormalities?

YES : Repair it. Then go to Step 4.

NO : Go to Step 2.

STEP 2. Check the intake charge pressure control system.

Refer to On-vehicle Service - Intake Charge Pressure Control System Check. Testing and Inspection

Q: Are there any abnormalities?

YES : Repair it. Then go to Step 4.

NO : Go to Step 3.

STEP 3. Check the turbocharger wastegate actuator.

Refer to On-vehicle Service - Turbocharger Wastegate Actuator Check. Testing and Inspection

Q:Are there any abnormalities?

YES : Repair or replace it. Then go to Step 4.

NO : Go to Step 4.

STEP 4. Test the OBD-II drive cycle.

1. Carry out test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 17. OBD-II Drive Cycle
2. Check the diagnostic trouble code (DTC).

Q: Is the DTC P0234 set?

YES : Retry the troubleshooting.

NO : The inspection is complete.