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How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2008 Lexus IS F. 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  9, AND PROCEED TO "NO IMAGE APPEARS ON MULTI-DISPLAY ")

    OTHER SYMPTOMS (GO TO STEP 3) 

  3. CHECK MULTIPLEX COMMUNICATION SYSTEM (BEAN) 
    1. Use the Techstream to check for normal function of the body multiplex communication system (See HOW TO PROCEED WITH TROUBLESHOOTING )

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

    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 DTC 

    HINT.

    If the system cannot enter the diagnostic mode, inspect each AVC-LAN communication component and repair or replace problem parts.

    A CODE IS OUTPUT (GO TO STEP 6) 

    A CODE IS NOT OUTPUT (GO TO STEP  9)

  6. DTC CLEAR 
    1. Clear the DTCs and finish the diagnostic mode

      HINT

      The currently output DTCs may not indicate actual malfunctions depending on the vehicle conditions

  7. RECHECK DTC 

    HINT

    • If the system cannot enter the diagnosis mode, inspect the AVC-LAN and all the components that connect to the AVC-LAN for short circuits
    • 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 system description on the diagnostic screen, as necessary (See SYSTEM DESCRIPTION  )
    • Check the diagnostic trouble code and inspect the area the code indicates

    A CODE IS OUTPUT (GO TO STEP 8) 

    A CODE IS NOT OUTPUT (GO TO STEP  9)

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

    NEXT:  GO TO STEP  11

  9. PROBLEM SYMPTOMS TABLE 
    1. Find the applicable symptom in the problem symptoms table (See PROBLEM SYMPTOMS TABLE  )

      HINT

      If the symptom does not recur and no code is output, perform the symptom reproduction method (See HOW TO PROCEED WITH TROUBLESHOOTING )

    THERE IS AN APPLICABLE SYMPTOM IN THE TABLE (GO TO STEP  11)

    THERE IS NO APPLICABLE SYMPTOM IN THE TABLE (GO TO STEP 10) 

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

    HINT.

    After clearing the DTCs, recheck for diagnostic trouble codes

  13. PERFORM CONFIRMATION TEST 

    NEXT: END 

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