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How To Proceed With Troubleshooting

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

HINT:

  1. VEHICLE BROUGHT TO WORKSHOP 
    • 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.

  3. INSPECT COMMUNICATION FUNCTION OF LARGE-SCALE MULTIPLEX COMMUNICATION SYSTEM (BEAN)* 
    1. Use the intelligent tester to check if the Multiplex Communication System (MPX) is functioning normally.
      COMMUNICATION FUNCTION OF LARGE-SCALE MULTIPLEX COMMUNICATION SYSTEM (BEAN)

      Result Proceed to
      MPX DTC is not output A
      MPX DTC is output B
  4. BASIC INSPECTION 
    1. Turn the ignition switch to ACC.
    2. Check whether or not the display appears on the radio receiver.

      Result 

      BASIC INSPECTION

      Result Proceed to
      Display appears A
      Display does not appear B
  5. CHECK FOR DTC 
    1. Check for DTCs and note any codes that are output.
    2. Delete the DTC.
    3. Recheck for DTCs. Based on the DTC output in (a), try to force output of the audio system DTC by simulating the operation indicated by the DTC.

      Result 

      DTC

      Result Proceed to
      DTC does not reoccur A
      DTC reoccurs B
      • B: Go to step   8 
      • A: GO TO NEXT STEP 
  6. PROBLEM SYMPTOMS TABLE 

    Result 

    RESULT REFERENCE TABLE

    Result Proceed to
    Fault is not listed in problem symptoms table A
    Fault is listed in problem symptoms table B
    • B: Go to step   8 
    • A: GO TO NEXT STEP 
  7. OVERALL ANALYSIS AND TROUBLESHOOTING 
    1. TERMINALS OF ECU 
    • GO TO NEXT STEP 
  8. ADJUST, REPAIR OR REPLACE 
    • END