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How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2007 Lexus GS 350. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

The intelligent tester can be used in steps  3,  4,  5,  7 and  11.

  1. VEHICLE BROUGHT TO WORKSHOP 

    NEXT: 

  2. CUSTOMER PROBLEM ANALYSIS 
    1. Confirm problem symptoms.

    NEXT: 

  3. CHECK MULTIPLEX COMMUNICATION SYSTEM 
    1. Check for DTCs (See DTC CHECK / CLEAR ).

      HINT:

      The 4WD control ECU sends the signals from indicator light to the gateway ECU via CAN communication, and the gateway ECU sends the signals to the combination meter assembly via multiplex communication system (BEAN).

    Result 

    RESULT CHART

    Result Proceed to
    DTC is not output A
    DTC is output B

    B: CHECK MULTIPLEX COMMUNICATION CIRCUIT 

    A: Go to next step 

  4. CHECK CAN COMMUNICATION SYSTEM 
    1. Check for DTCs (See DTC CHECK / CLEAR ).

      HINT:

      The ECU of this system is connected to the CAN communication system.

      Therefore before starting troubleshooting, make sure to check that there is no trouble in CAN communication system.

    Result 

    RESULT CHART

    Result Proceed to
    DTC is not output A
    DTC is output B

    B: CHECK CAN COMMUNICATION CIRCUIT 

    A: Go to next step 

  5. CHECK DTC 
    1. Check for DTCs (See DTC CHECK / CLEAR ).
      1. Record the DTCs.
    2. Clear the DTCs.
    3. Recheck for DTCs.
      1. Simulate the malfunction and check if the DTCs are output again.

    Result 

    RESULT CHART

    Result Proceed to
    DTC is output A
    DTC is not output B
    DTCs are not output, and the malfunction cannot be simulated or checked C

    B: GO TO STEP   10 

    C: SYMPTOM SIMULATION 

    A: Go to next step 

  6. DTC CHART 

    NEXT: 

  7. CIRCUIT INSPECTION 

    NEXT: 

  8. REPAIR 

    NEXT: 

  9. CONFIRMATION TEST 

    NEXT: END 

  10. PROBLEM SYMPTOMS TABLE 

    NEXT: 

  11. CIRCUIT INSPECTION 

    NEXT: 

  12. CONFIRMATION TEST 

    NEXT: END