P0236

Diagnostic Chart (Part 1 Of 2):

Diagnostic Chart (Part 2 Of 2):

Schematic:

CIRCUIT DESCRIPTION
The PCM operates a solenoid to control the 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 RUNNING THE DTC
The engine speed is than 2400 RPM for test 1.

or

The engine speed is more than 1800 RPM but less than 2400 RPM for test 2.

CONDITIONS FOR SETTING THE DTC
^ The boost pressure is greater than, less than, or equal to 20 kPa from a desired value that is internal to the PCM for test 1.
^ The conditions were met for 10 seconds.

or

^ The boost pressure is greater than, less than, or equal to 20 kPa from a desired value that is internal to PCM for test 2.
^ 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 in which the diagnostic runs and fails.
^ A faulty performance condition will exist.
^ The PCM will reduce the maximum fuel level.
^ The PCM will disable the Torque Converter Clutch (TCC).

CONDITIONS FOR CLEARING THE MIL/DTC
^ The PCM will turn the MIL off after 3 consecutive trips without a fault condition.
^ A History DTC will clear after 40 consecutive warm-up cycles, if no failures are reported by this or any other emissions related diagnostic.

Use a scan tool in order to clear the DTCs.

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

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

TEST DESCRIPTION
The numbers below refer to the step numbers 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.
9. This step will check for a skewed boost pressure sensor.