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Home >> Subaru >> 2017 >> BRZ Limited, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostics - Introduction) >> EFI system (FA20) >> How to troubleshoot
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How to troubleshoot

  1. Bring in the car

    Next

  2. Interview and phenomenon check

    Next

  3. Read DTC
    1. Check the DTC(s) related to engine and CAN communication system and the freeze frame data.
    2. When DTC is output or freeze frame data is displayed, store it.
      CAUTION: When clearing the DTC and/or freeze frame data, be sure to store the data before clearing it.
    RESULT REFERENCE

    Result Go to
    When DTC not related to CAN communication system is output. A
    When no DTC is output. B
    When DTC related to CAN communication system is output. C

    B: Go to Step  12.

    C: Go to CAN communication information. (Refer to How to troubleshoot )

    A: Go to next Step.

  4. Check repeatability of malfunction
    1. Perform repeatability test, referring to the result of the interview.
    RESULT REFERENCE

    Result Go to
    When malfunction is repeated A
    When malfunction is not repeated B

    B: Go to Step  9.

    A: Go to next Step.

  5. List of diagnostic codes (main inspection parts) or troubleshooting for DTC
    1. Refer to list of diagnostic codes, and perform troubleshooting for DTC. (Refer to DTC table )
    RESULT REFERENCE

    Result Go to
    When faulty points are not determined. A
    When faulty points are determined. B

    B: Go to Step  7.

    A: Go to next Step.

  6. System circuit inspection
    1. If the faulty parts are not specified after the diagnosis according to the inspection procedure, refer to the inspection method of the electrical circuit, and perform the circuit inspection. (For system circuit figure , refer to .)

    Next

  7. Repair faulty points

    Next

  8. Read DTC (Refer to Checking/clearing DTC )

    Next: Complete

  9. Inspection for problems that do not normally occur (Refer to Checking/clearing DTC )

    Next

  10. Repair faulty points

    Next

  11. Read DTC (Refer to Checking/clearing DTC )

    Next: Complete

  12. Check repeatability of malfunction
    1. Perform repeatability test, referring to the result of the interview.
    RESULT REFERENCE

    Result Go to
    When malfunction is repeated A
    When malfunction is not repeated B

    B: Go to Step  19.

    A: Go to next Step.

  13. Symptom table
    1. Estimate the location of the faulty points from the result of the interview, and perform necessary inspection. (Refer to Symptom table )
    RESULT REFERENCE

    Result Go to
    Faulty points are not determined. A
    Faulty points are determined. B

    B: Go to Step  17.

    A: Go to next Step.

  14. Basic inspection
    1. Estimate the location of the faulty points from the result of the interview, and perform necessary inspection. (Refer to Symptom table )
    RESULT REFERENCE

    Result Go to
    Faulty points are not determined. A
    Faulty points are determined. B

    B: Go to Step  17.

    A: Go to next Step.

  15. Inspection with SSM4
    1. Check the data monitor and perform the active test. (Refer to Data monitor/active test )
    RESULT REFERENCE

    Result Go to
    Faulty points are not determined. A
    Faulty points are determined. B

    B: Go to Step  17.

    A: Go to next Step.

  16. System circuit inspection
    1. If any defective point is not located in the areas outside of the engine control computer after diagnosis according to the inspection procedure, refer to the inspection method of the electrical circuit, and perform the circuit inspection. (For system circuit figure , refer to .)

    Next

  17. Repair faulty points

    Next

  18. Check trouble phenomenon
    1. Perform driving test referring to the result of the interview, and check that the malfunction does not recur.

    Next: Complete

  19. Symptom table
    1. Estimate the location of the faulty points from the result of the interview, and perform necessary inspection. (Refer to Symptom table )
    RESULT REFERENCE

    Result Go to
    Faulty points are not determined. A
    Faulty points are determined. B

    B: Go to Step  24.

    A: Go to next Step.

  20. Basic inspection
    1. Estimate the location of the faulty points from the result of the interview, and perform necessary inspection. (Refer to EFI system (FA20) )
    RESULT REFERENCE

    Result Go to
    When faulty points are not determined. A
    When faulty points are determined. B

    B: Go to Step  24

    A: Go to next Step.

  21. Inspection with SSM4
    1. Check the data monitor and perform the active test. (Refer to Data monitor/active test )
    RESULT REFERENCE

    Result Go to
    Faulty points are not determined. A
    Faulty points are determined. B

    B: Go to Step  24

    A: Go to next Step.

  22. System circuit inspection
    1. If any defective point is not located in the areas outside of the engine control computer after diagnosis according to the inspection procedure, refer to the inspection method of the electrical circuit, and perform the circuit inspection. (For system circuit figure , refer to .)

    Next

  23. Inspection for problems that do not normally occur (Refer to Checking/clearing DTC )

    Next

  24. Repair faulty points

    Next

  25. Check trouble phenomenon
    1. Perform driving test referring to the result of the interview, and check that the malfunction does not recur.

    Next: Complete

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