P0236

Diagnostic Chart:

Wiring Chart:

CIRCUIT DESCRIPTION

The PCM operates a solenoid to the control boost. This solenoid is normally open. By providing a ground path, the PCM energizes the solenoid which then allows a vacuum to pass to the wastegate valve. During normal operation, the PCM compares the wastegate duty cycle signal with the boost signal and makes corrections in the duty cycle accordingly

CONDITIONS FOR SETTING THE DTC

- The engine speed greater than 2400 RPM.

- The fuel rate is greater than 20 mm.

- The boost pressure is greater than, less than, or equal to 20 kPa from desired (internal to PCM).

- The conditions were met for 10 seconds.

or

- The engine speed is greater than 1800 but less than 2400 RPM.

- The fuel rate is greater than 20 mm.

- The conditions were met for 12 seconds.

ACTION TAKEN WHEN THE DTC SETS

- The PCM illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive drive trip the diagnostic runs and fails.

- The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the Failure Records store this information. If the diagnostic reports a failure on the second consecutive drive trip, the Freeze Frame records the operating conditions at the time of failure and updates the Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC

- The PCM will turn the MIL OFF after three consecutive trips without a fault condition.

- A History DTC will clear after forty consecutive warm-up cycles during which the diagnostic does not tail (the coolant temperature has risen 5°C (40°F) from the start up coolant temperature and the engine coolant temperature exceeds 71°C (160°F) during that same ignition cycle).

- Use of a Scan Tool will clear the DTC codes.

DIAGNOSTIC AIDS

A vacuum leak or a pinched vacuum line may cause a DTC P0236. Check all of the vacuum lines and the components connected to the hoses for any leaks or sharp bends. Check the vacuum source. Also check for a proper vacuum line routing.

The turbocharger actuator uses a pulse width modulated vacuum solenoid that causes the vacuum to fluctuate under normal conditions. A steady vacuum reading indicates a restricted solenoid vent filter or a solenoid vent orifice.

TEST DESCRIPTION

The number(s) below are the step number(s) on the Diagnostic Table.

3. This will check the wastegate solenoid and the filter. A plugged filter will not allow the solenoid to vent, which will cause an overboost condition.

5. This step checks the turbocharger wastegate actuator for vacuum leaks. The actuator must hold a vacuum.

6. This step will check for vacuum leaks at the lines.