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DTC P003A: Turbocharger/Supercharger Boost Control "A" Position Exceeded Learning Limit: Notes

DTC detecting condition: 

Detected when two consecutive driving cycles with fault occur.

Trouble symptom: 

NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>Basic Diagnostic Procedure>PROCEDURE .
  1. CHECK DTC  .
    1. Turn the ignition switch to ON.
    2. Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Ref. to COMMON (diag)>DIAGNOSTIC TROUBLE CODE (DTC) .

    Is DTC other than P003A displayed? (Current malfunction)

    Yes  : Check the appropriate DTC using the "Diagnostic Trouble Code (DTC)". Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>Diagnostic Trouble Code (DTC)>LIST .

    No  : Go to  2.

  2. CHECK DATA MONITOR  .

    Using the Subaru Select Monitor, read the value in [Electric Waste Gate Valve Position Sensor Learning Value at the Full-closed Position].

    NOTE: For detailed operation procedures, refer to "Common (Diagnostics)". Ref. to COMMON (diag)>DATA MONITOR .

    Is the value in [Electric Waste Gate Valve Position Sensor Learning Value at the Full-closed Position] less than -3 mm (-0.12 in) or more than 4.3 mm (0.17 in)?

    Yes  : Go to  3.

    No  : Even if DTC is detected, the circuit has returned to a normal condition at this time.

    Reproduce the failure, and then perform the diagnosis again.

    NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness or temporary contamination and clogging at the valve port may be the cause.
  3. CHECK APPEARANCE OF TURBOCHARGER (ELECTRONIC WASTEGATE VALVE)  .
    1. Turn the ignition switch to OFF.
    2. Remove the turbocharger. Ref. to INTAKE (INDUCTION) (H4DOTC)>Turbocharger>REMOVAL .
    3. Check the appearance of turbocharger to make sure that there is no foreign matter pinched in the electronic wastegate valve.
      CAUTION: Do not remove the electronic air by-pass valve and electronic wastegate valve since they are non-disassembled parts.

    Is the check result OK?

    Yes  : Replace the turbocharger. Ref. to INTAKE (INDUCTION) (H4DOTC)>Turbocharger>REMOVAL .

    No  : Remove the foreign matters from the turbocharger.