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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 interview check list. Ref. to ENGINE (DIAGNOSTICS) (H4DO (EXCEPT FOR HEV))>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) (H4DO (EXCEPT FOR HEV))>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) (H4DO (EXCEPT FOR HEV))>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 "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  : Inspection using "Basic Diagnostic Procedure" of LAN system. Ref. to LAN SYSTEM (DIAGNOSTICS) (EXCEPT FOR HEV)>BASIC DIAGNOSTIC PROCEDURE .

  4. CHECK DTC  .

    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 for [Engine] displayed? (Current malfunction)

    Yes  : Save DTC and freeze frame data, then repair the trouble cause. Ref. to COMMON (DIAG)>DIAGNOSTIC TROUBLE CODE (DTC) . Ref. to COMMON (DIAG)>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) (H4DO (EXCEPT FOR HEV))>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 (DIAG)>CLEAR MEMORY .
    3. Execute the inspection mode. Ref. to ENGINE (DIAGNOSTICS) (H4DO (EXCEPT FOR HEV))>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) (H4DO (EXCEPT FOR HEV))>ALL READINESS DIAGNOSTIC CODE(S) .
    5. 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 for [Engine] displayed? (Current malfunction)

      Yes  : Check the connection of connector. If there is no faulty connector, perform the diagnosis for the displayed DTCs. Ref. to ENGINE (DIAGNOSTICS) (H4DO (EXCEPT FOR HEV))>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC) .

      No  : Finish the diagnosis.

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