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Detailed Flow

  1. GET INFORMATION FOR SYMPTOM 

    Get the detailed information from the customer about the symptom (the condition and the environment when the incident/malfunction occurred) using the "Diagnostic Work Sheet". (Refer to Diagnostic Work Sheet ).

    Malfunction information, obtained

    GO TO 2.

  2. CHECK DTC 
    1. Check DTC of "ALL DTC Reading".
    2. Perform the following procedure if DTC is displayed.
      • Record DTC and freeze frame data. (Print them out with CONSULT or GST.)
      • Erase only DTC of "ENGINE". Refer to How to Erase DTC and 1st Trip DTC in Diagnosis Description .
      • Study the relationship between the cause detected by DTC and the symptom described by the customer. (Symptom Table is useful. Refer to Symptom Table ).
    3. Check related service bulletins for information.

    Is any symptom described and is any DTC detected?

    Symptom is described, DTC is detected

    GO TO 3.

    Symptom is described, DTC is not detected

    GO TO 4.

    Symptom is not described, DTC is detected

    GO TO 5.

  3. CONFIRM THE SYMPTOM 

    Try to confirm the symptom described by the customer (except MIL ON).

    Also study the normal operation and fail-safe related to the symptom. Refer to Symptom Description and Fail-safe .

    Diagnosis Work Sheet is useful to verify the incident.

    Verify relation between the symptom and the condition when the symptom is detected.

    GO TO 5.

  4. CONFIRM THE SYMPTOM 

    Try to confirm the symptom described by the customer.

    Also study the normal operation and fail-safe related to the symptom. Refer to Symptom Description and Fail-safe .

    Diagnosis Work Sheet is useful to verify the incident.

    Verify relation between the symptom and the condition when the symptom is detected.

    GO TO 6.

  5. PERFORM DTC CONFIRMATION PROCEDURE 

    Perform DTC CONFIRMATION PROCEDURE for the displayed DTC, and then check that DTC is detected again.

    If two or more DTCs are detected, Refer to DTC Inspection Priority Chart  and determine trouble diagnosis order.

    NOTE:
    • Freeze frame data is useful if the DTC is not detected.
    • Perform Component Function Check if DTC CONFIRMATION PROCEDURE is not included in this Service Information. This simplified check procedure is an effective alternative though DTC cannot be detected during this check.

      If the result of Component Function Check is NG, it is the same as the detection of DTC by DTC CONFIRMATION PROCEDURE.

    Is DTC detected?

    YES

    GO TO 10.

    NO

    Check according to Intermittent Incident .

  6. PERFORM BASIC INSPECTION 

    Refer to Work Procedure .

    Do you have CONSULT?

    YES

    GO TO 7.

    NO

    GO TO 9.

  7. PERFORM SPEC IN DATA MONITOR MODE 

    SYMBOL With CONSULT

    Check that "MASS AIR FLOW SENSOR (Hz) B1", "B/FUEL SCHDL", and "A/F ALPHA-B1" are within the SP value using "SPEC" in "DATA MONITOR" mode with CONSULT. Refer to Component Function Check .

    Is the measurement value within the SP value?

    YES

    GO TO 9.

    NO

    GO TO 8.

  8. DETECT MALFUNCTIONING PART BY TROUBLE DIAGNOSIS - SPECIFICATION VALUE 

    Detect malfunctioning part according to Diagnosis Procedure .

    Is a malfunctioning part detected?

    YES

    GO TO 11.

    NO

    GO TO 9.

  9. DETECT MALFUNCTIONING SYSTEM BY SYMPTOM TABLE 

    Detect malfunctioning system according to Symptom Table . based on the confirmed symptom in step 4, and determine the trouble diagnosis order based on possible causes and symptoms.

    GO TO 10.

  10. DETECT MALFUNCTIONING PART BY DIAGNOSIS PROCEDURE 

    Inspect according to Diagnosis Procedure of the system.

    NOTE: The Diagnosis Procedure in ENGINE CONTROL articles described is based on open circuit inspection. A short circuit inspection is also required for the circuit check in the Diagnosis Procedure. For details, Refer to Circuit Inspection .

    Is a malfunctioning part detected?

    YES

    GO TO 11.

    NO

    Monitor input data from related sensors or check voltage of related ECM terminals using CONSULT. Refer to Physical Values .

  11. REPAIR OR REPLACE THE MALFUNCTIONING PART 

    SYMBOL With CONSULT

    1. Repair or replace the malfunctioning part.
    2. Reconnect parts or connectors disconnected during Diagnosis Procedure again after repair and replacement.
    3. Check DTC. If DTC is displayed, erase it. Refer to How to Erase DTC and 1st Trip DTC in Diagnosis Description .

    GO TO 12.

  12. FINAL CHECK 

    When DTC was detected in step 2, perform DTC CONFIRMATION PROCEDURE or Component Function Check again, and then make sure that the malfunction have been repaired securely.

    When symptom was described from the customer, refer to confirmed symptom in step 3 or 4, and make sure that the symptom is not detected.

    Is DTC detected and does symptom remain?

    YES

    DTC is detected: GO TO 10.

    YES

    Symptom remains: GO TO 6.

    NO

    Before returning the vehicle to the customer, make sure to erase unnecessary DTC in ECM. (Refer to "How to Erase DTC and 1st Trip DTC" in Diagnosis Description ).

    NO

    I/M examination, requested from the customer: GO TO 13.

  13. PREPARE FOR I/M EXAMINATION 
    1. Set SRT codes. Refer to Work Procedure .
    2. Erase permanent DTCs. Refer to Work Procedure .

    INSPECTION END.

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