2007 Lexus SC 430FACTORY OEM SERVICE PROCEDURE

How To Proceed With Troubleshooting

HINT:

  • Use these procedures to troubleshoot the window defogger system.
  • *: Use the intelligent tester.
  1. VEHICLE BROUGHT TO WORKSHOP 
  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.

      Result 

      RESULT REFERENCE CHART

      Result Proceed to
      MPX DTC is not output A
      MPX DTC is output B

    B:  GO to MULTIPLEX COMMUNICATION SYSTEM

    A: Go to Next Step 

  4. PROBLEM SYMPTOMS TABLE 

    Result 

    RESULT REFERENCE CHART

    Result Proceed to
    Fault is not listed in problem symptoms table A
    Fault is listed in problem symptoms table B

    B: Go to step  6

    A: Go to Next Step 

  5. OVERALL ANALYSIS AND TROUBLESHOOTING* 
    1. (see TERMINALS OF ECU  ).
    2. (see DATA LIST / ACTIVE TEST  ).
    3. (see ON-VEHICLE INSPECTION  ).
  6. ADJUST, REPAIR OR REPLACE 
  7. CONFIRMATION TEST 

    NEXT: END 

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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