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Basic Diagnostic Procedure: Procedure: Engine

Fig 1: Engine Diagnosis Flow Chart
G11257233Courtesy of SUBARU OF AMERICA, INC.
  1. CHECK ENGINE START FAILURE.
    1. Ask the customer when and how the trouble occurred using the interview check list. Ref. to ENGINE (DIAGNOSTICS) >Check List for Interview>CHECK .
    2. Start the engine.

    Does the engine start?

    Yes: Go to 2  .

    No: Inspection using "Diagnostics for Engine Starting Failure" Ref. to ENGINE (DIAGNOSTICS) >Diagnostics with Phenomenon .

  2. CHECK ILLUMINATION OF MALFUNCTION INDICATOR LIGHT  .

    Check the illumination status of malfunction indicator light.

    Does the malfunction indicator light illuminate?

    Yes: Go to  3.

    No: Check using "Diagnostics with Phenomenon". Ref. to ENGINE (DIAGNOSTICS) >Diagnostics with Phenomenon .

  3. CHECK COMMUNICATION STATUS  .
    1. Turn the ignition switch to OFF.
    2. Connect the Subaru Select Monitor or general scan tool to the data link connector.
    3. Turn the ignition switch to ON, and run the Subaru Select Monitor or general scan tool.
      NOTE:
      • SUBARU SELECT MONITOR

        For detailed operation procedures, refer to the "Subaru Select Monitor ".

      • General scan tool

    For detailed operation procedures, refer to the general scan tool operation manual.

    Does Subaru Select Monitor or general scan tool communicate with vehicle normally?

    Yes: Go to  4.

    No: Inspection using "Basic Diagnostic Procedure" of LAN system Ref. to LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure .

  4. CHECK DTC  .

    Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Ref. to ENGINE (DIAGNOSTICS) >Diagnostic Trouble Code (DTC) .

    NOTE:
    • SUBARU SELECT MONITOR

      For detailed operation procedures, refer to "Data Monitor". Ref. to ENGINE (DIAGNOSTICS) >Data Monitor .

    • General scan tool

      For detailed operation procedures, refer to the general scan tool operation manual.

    Is DTC displayed on Subaru Select Monitor or general scan tool?

    Yes: Record DTC and freeze frame data, then repair the trouble cause. Ref. to ENGINE (DIAGNOSTICS) >Diagnostic Trouble Code (DTC) .

    After repair, go to the next step.

    Go to  5.

    No: Repair the related parts.

    NOTE: If DTC is not shown on display although the malfunction indicator light illuminates, perform the diagnosis of malfunction indicator light circuit or combination meter. Ref. to ENGINE (DIAGNOSTICS) >Warning Light Illumination Pattern .
  5. FINAL CHECK  .
    1. Connect all connectors.
    2. Using the Subaru Select Monitor or a general scan tool, perform the clear memory of [Engine].
    3. Execute the inspection mode. Ref. to ENGINE (DIAGNOSTICS) >Inspection Mode . Ref. to ENGINE (DIAGNOSTICS) >Inspection Mode .
    4. Read the readiness code of [Engine] using Subaru Select Monitor and check that the concerned DTC is completed. Ref. to ENGINE (DIAGNOSTICS) >Inspection Mode .
    5. Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Ref. to ENGINE (DIAGNOSTICS) >Diagnostic Trouble Code (DTC) .

    Is DTC displayed on Subaru Select Monitor or general scan tool?

    Yes: Check the connection of connector. If there is no faulty connector, perform the diagnosis for the displayed DTCs. Ref. to ENGINE (DIAGNOSTICS) >Diagnostic Procedure with Diagnostic Trouble Code (DTC) .

    No: Finish the diagnosis.

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