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How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2008 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
  1. VEHICLE BROUGHT TO WORKSHOP 
  2. INSPECT BATTERY VOLTAGE 

    Standard voltage: 10 to 14 V 

    If the voltage is below 10 V, recharge or replace the battery before proceeding.

  3. INSPECT COMMUNICATION FUNCTION OF LARGE-SCALE MULTIPLEX COMMUNICATION SYSTEM (BEAN) 
    1. Using Techstream, check if the Multiplex Communication System (MPX) is functioning normally.

      Result 

      RESULT REFERENCE

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

    B:  Go to MULTIPLEX COMMUNICATION SYSTEM

    A: Go to Next Step 

  4. BASIC INSPECTION 
    1. Turn the ignition switch on (IG).
    2. Check whether or not the radio receiver and multi-display (accessory meter) turn on.

      Result 

      RESULT REFERENCE

      Result Proceed to
      Radio receiver and multi-display (accessory meter) turn on A
      Radio receiver and multi-display (accessory meter) do not turn on B

    B:  Go to step  7

    A: Go to Next Step 

  5. CHECK FOR DTC 
    1. Check for DTCs and note any codes that are output.
    2. Delete the DTCs.
    3. Recheck by simulating the operation indicated by the DTC.

      HINT:

      • If the system cannot enter the diagnosis mode, inspect each AVC-LAN communication signal and repair or replace the problem parts.
      • Even if the malfunction symptom is not confirmed, check the DTCs. This is because the system stores past DTCs.
      • Check and clear past DTCs. Then check for DTCs.

        Result 

        RESULT REFERENCE

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

    B:  Go to step  7

    A: Go to Next Step 

  6. DIAGNOSTIC TROUBLE CODE CHART 

    Find the output code on the diagnostic trouble code chart (See DIAGNOSTIC TROUBLE CODE CHART  ).

    NEXT:  Go to step  9

  7. PROBLEM SYMPTOMS TABLE 

    Refer to the PROBLEM SYMPTOMS TABLE  .

    Result 

    RESULT REFERENCE

    Result Proceed to
    Fault is not listed in problem symptoms table A
    Fault is listed in problem symptoms table B

    B:  Go to step  9

    A: Go to Next Step 

  8. OVERALL ANALYSIS AND TROUBLESHOOTING 
    1. Terminals of ECU (See TERMINALS OF ECU  ).
  9. ADJUST, REPAIR OR REPLACE 
  10. CONFIRMATION TEST 

    NEXT : END