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How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2004 Lexus LS 430. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

  1. VEHICLE BROUGHT TO WORKSHOP 
  2. CUSTOMER PROBLEM ANALYSIS CHECK AND SYMPTOM CHECK (See  CUSTOMER PROBLEM ANALYSIS CHECK  ) 
  3. INSPECT COMMUNICATION FUNCTION OF LARGE-SCALE MULTIPLEX COMMUNICATION SYSTEM (BEAN) 
    1. Use the hand-held tester to check for normal function of the multiplex communication system.
      1. (ECU unconnected, communication line malfunctioning) Without code outputs, proceed to A.
      2. (ECU unconnected, communication line malfunctioning) With code outputs, proceed to B.

    B: Go to MULTIPLEX COMMUNICATION SECTION (SEE  DIAGNOSTIC TROUBLE CODE CHART  ) 

    A: Go to next step 

  4. DTC CHECK (See  DTC CHECK/CLEAR  ) 
    1. Check for DTC and note any codes that are output.
    2. Delete the DTC.
    3. Recheck for DTCs. Try to prompt the DTC by simulating the original activity that the DTC suggests.
      1. If the DTC does not reoccur, proceed to A.
      2. If the DTC reoccurs, proceed to B

    B: Go to step 6 

    A: Go to next step 

  5. PERFORM SYMPTOM TABLE (See  PROBLEM SYMPTOMS TABLE  ) 
    1. If the fault is not listed on the problem symptoms table, proceed to A.
    2. If the fault is listed on the problem symptoms table, proceed to B.

    B: Go to step 7 

    A: Go to next step 

  6. OVERALL ANALYSIS AND TROUBLE SHOOTING 
    1. DATA LIST/ACTIVE TEST (see DATA LIST/ACTIVE TEST )
      1. Inspection with the hand-held tester (DATA LIST).
      2. Inspection with the hand-held tester (ACTIVE TEST).
    2. Terminals of ECU (see TERMINALS OF ECU )
    3. On-vehicle inspection (see ON-VEHICLE INSPECTION )
    4. Inspection (see INSPECTION )
  7. ADJUST, REPAIR OR REPLACE 
  8. CONFIRMATION TEST 

    END