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How To Proceed With Troubleshooting

HINT: 

  1. VEHICLE BROUGHT TO WORKSHOP 

    NEXT: Go to next step 

  2. INSPECT BATTERY VOLTAGE 

    Standard voltage

    11 to 14 V

    If the voltage is below 11 V, recharge or replace the battery before proceeding to the next step.

    NG → CHARGE OR REPLACE BATTERY 

    OK: Go to next step 

  3. CHECK MULTIPLEX COMMUNICATION SYSTEM 
    1. Use the Techstream to check if the multiplex communication system (MPX) is functioning normally.
      RESULT

      DTC Condition Proceed to
      MPX DTC is not output A
      MPX DTC is output B

      B → GO TO MULTIPLEX COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 

      A: Go to next step 

  4. CHECK CAN COMMUNICATION SYSTEM 
    1. Use the Techstream to check if the CAN communication system is functioning normally.
      RESULT

      DTC Condition Proceed to
      CAN DTC is not output A
      CAN DTC is output B

      B → GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 

      A: Go to next step 

  5. CHECK FOR DTC 
    1. Check for DTCs.
      1. Record the DTCs.
    2. Clear the DTCs.
    3. Recheck for DTCs.
      1. Attempt to duplicate the malfunction and check if the DTCs are output again. Refer to DTC CHECK / CLEAR .
        RESULT

        DTC Condition Proceed to
        DTC is not output A
        DTC is output B
        No DTC is output, and malfunction cannot be duplicated or checked C

      B → GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART  

      C → GO TO SYMPTOM SIMULATION. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 

      A: Go to next step 

  6. PROBLEM SYMPTOMS TABLE 

    Refer to Problem Symptoms Table. Refer to PROBLEM SYMPTOMS TABLE .

    RESULT

    Result Proceed to
    Fault is not listed in Problem Symptoms Table A
    Fault is listed in Problem Symptoms Table B

    B → Go to step 7 

    A: Go to next step 

  7. PERFORM TROUBLESHOOTING BASED ON MALFUNCTION SYMPTOM 
    1. Data List / Active Test. Refer to DATA LIST / ACTIVE TEST 
    2. Terminals of ECU. Refer to TERMINALS OF ECU 

      NEXT: Go to next step 

  8. ADJUST, REPAIR OR REPLACE 

    NEXT: Go to next step 

  9. CONFIRMATION TEST 

    NEXT → END