P0238

Diagnostic Chart:

Wiring Chart:

CIRCUIT DESCRIPTION

The PCM operates a solenoid to control boost. This solenoid is normally open. By providing a ground path, the PCM energizes the solenoid which allows 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 to the duty cycle accordingly.

CONDITIONS FOR SETTING THE DTC

^ The Boost Pressure is greater than or equal to 4.8 volts (202 kPa).

^ The engine speed is less than 3506 RPM.

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. lithe 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 fail (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) of that same ignition cycle).

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

DIAGNOSTIC AIDS

Very little boost can be attained by revving the engine in neutral.

An intermittent can be caused by the following:

^ Poor connections

^ A rubbed through wire insulation

^ A broken wire inside of the insulation

TEST DESCRIPTION

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

3. This Step will make sure the PCM is responding to a low signal voltage. This will indicate that the PCM is OK.

9. If the Scan Tool display is still less than or equal to 9 kPa by disconnecting the PCM, the short to voltage is in the wiring.

10. lithe voltmeter value stays the same by disconnecting the PCM, the short to voltage is in the wiring.