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Basic Diagnostic Procedure: Procedure

  1. CHECK ENGINE START FAILURE  .
    1. Ask the customer when and how the trouble occurred using the Check List for Interview. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>CHECK LIST FOR INTERVIEW>CHECK .
    2. Start the engine.

    Does the engine start?

    Yes:  Go to  2.

    No:  Check "Diagnostics with Phenomenon". Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>DIAGNOSTICS WITH PHENOMENON .

  2. CHECK ILLUMINATION OF MALFUNCTION INDICATOR LIGHT 

    Check the illumination status of malfunction indicator light. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>WARNING LIGHT ILLUMINATION PATTERN>PROCEDURE .

    Does the malfunction indicator light illuminate?

    Yes:  Go to  3.

    No:  Check "Warning Light Illumination Pattern". Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>WARNING LIGHT ILLUMINATION PATTERN .

  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 "Help" of application.

    • 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:  Perform the inspection according to "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 COMMON (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

    Is DTC for [Engine] displayed? (Current code)

    Yes:  Save DTC and freeze frame data, then repair the trouble cause. Ref. to COMMON (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) . Ref. to COMMON (DIAGNOSTICS)>FREEZE FRAME DATA .

    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) (H4DOTC)>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]. Ref. to COMMON (DIAGNOSTICS)>CLEAR MEMORY .
    3. Execute the inspection mode. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>INSPECTION MODE .
    4. Read the readiness code of [Engine] using Subaru Select Monitor and check that the concerned self-diagnosis is completed. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>ALL READINESS DIAGNOSTIC CODE(S) .
    5. Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Ref. to COMMON (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

    Is DTC for [Engine] displayed? (Current code)

    Yes:  Check the connection of connector. If there is no faulty connector, perform the diagnosis for the displayed DTCs. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>DIAGNOSTIC TROUBLE CODE (DTC)>LIST .

    No:  Finish the diagnosis.

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