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How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2006 Lexus RX 400h. However, it is still accessible from the selected car via links, so may be relevant.
  1. VEHICLE BROUGHT INTO A WORKSHOP 
  2. DIAGNOSTIC QUESTIONING AND SYMPTOM CONFIRMATION 
    1. Ask the customer about symptoms and confirm malfunctions.

    THE SCREEN DISPLAYS NOTHING (GO TO STEP   6 , AND PROCEED TO "BLACK SCREEN (NO IMAGE APPEARS ON NAVIGATION/AUDIO SCREEN)") 

    OTHER SYMPTOMS (GO TO STEP 3) 

  3. CHECK MULTIPLEX COMMUNICATION SYSTEM (BEAN) 
    1. Use the intelligent tester to check for normal function of the body multiplex communication system.

    A CODE IS OUTPUT (PROCEED TO " MULTIPLEX COMMUNICATION  ") 

    A CODE IS NOT OUTPUT (GO TO STEP 4) 

  4. CONFIRM THE SYSTEM NORMAL CONDITION 

    APPLICABLE (THIS IS NOT A MALFUNCTION) 

    NOT APPLICABLE (GO TO STEP 5) 

  5. CHECK THE DIAGNOSTIC TROUBLE CODES 

    HINT:

    • If the system cannot enter the diagnosis mode, inspect each AVC-LAN communication signal and repair or replace problem parts.
    • Even if the malfunction symptom is not confirmed, check for diagnostic trouble codes. This is because the system stores past diagnostic trouble codes.
    • Refer to the detailed description on the diagnostic screen, as necessary (See NAVIGATION CHECK MODE  ).
    • Check and clear past diagnostic trouble codes. Check the diagnostic trouble code and inspect the area the code indicates.

    A CODE IS OUTPUT (GO TO STEP 6) 

    A CODE IS NOT OUTPUT (GO TO STEP   7 ) 

  6. DIAGNOSTIC TROUBLE CODE CHART 
    1. Find the output code on the diagnostic trouble code chart.

    NEXT GO TO STEP   9 

  7. PROBLEM SYMPTOMS TABLE 
    1. Find the applicable symptom code in the problem symptoms table.

      HINT:

      If the symptom does not recur and no code is output, perform the symptom reproduction method (See HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS ).

    THERE IS AN APPLICABLE SYMPTOM CODE IN THE TABLE (GO TO STEP   9 ) 

    THERE IS NO APPLICABLE SYMPTOM CODE IN THE TABLE (GO TO STEP 8) 

  8. CHECK THE ECU TERMINAL ARRANGEMENT BASED ON THE MALFUNCTION SYMPTOM 
  9. CHECK THE CIRCUIT 
    1. Adjust, repair or replace as necessary.
  10. RECHECK THE DIAGNOSTIC TROUBLE CODE 

    HINT:

    After deleting the DTC, recheck for diagnostic trouble codes.

  11. PERFORM CONFIRMATION TEST 

    NEXT: END 

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