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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:

Use this procedure to troubleshoot the wireless door lock control system.

The intelligent tester II should be used in steps 3, 4 and 7.

  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 stop, communication line malfunctioning) Without code output, proceed to A.
      2. (ECU unconnected, communication stop, communication line malfunctioning) With code output, proceed to B.

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

    A:  Go to next step

  4. CHECK FOR DTCS (See  DTC CHECK/CLEAR  ) 
    1. Check for DTCs 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 suggested.
      1. If the DTC does not reoccur, proceed to A.
      2. If the DTC reoccurs, proceed to B.

    B: Go to step 7 

    A:  Go to next step

  5. PROBLEM SYMPTOMS 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 TROUBLESHOOTING 
    1. DATA LIST/ACTIVE TEST (see DATA LIST/ACTIVE TEST )
      1. Inspect with the hand-held tester (DATA LIST).
      2. Inspect with the hand-held tester (ACTIVE TEST).
    2. Terminals of ECU (see TERMINALS OF ECU )
    3. On-vehicle inspection (see ON-VEHICLE INSPECTION )
  7. ADJUSTMENT, REPAIR OR REPLACEMENT 
  8. CONFIRMATION TEST 

END