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 then
allows vacuum to pass to the wastegate valve. During normal operation,
the PCM monitors the boost sensor signal for high and low limits.
Conditions for Running the DTC
| • | The PCM performs this DTC diagnostic continuously. |
| • | The ignition switch is in the On position. |
Conditions for Setting the DTC
| • | The boost pressure is less than 40 kPa (.78 volts). |
| • | All diagnostic conditions met for 2 seconds. |
Action Taken When the DTC Sets
| • | The PCM illuminates the malfunction indicator lamp (MIL) on the
second consecutive drive trip that 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 will 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 clears after forty consecutive warm-up cycles,
if this or any other emission related diagnostic does not report any failures. |
Diagnostic Aids
Important: Remove any debris from the PCM module connector surfaces before servicing
the PCM module. Inspect the PCM module connector gaskets when diagnosing/replacing
the module. Ensure that the gaskets are installed correctly.
The gaskets prevent contaminate intrusion into the PCM module.
Check for opens or short to ground in the signal circuit or for an open
in the 5 volt ref circuit.
An intermittent may be caused by the following connections:
| • | Poor connections (terminal tension). |
| • | Rubbed through wire insulation. |
| • | Broken wire inside the insulation. |
