2008 Lexus GS 460FACTORY OEM SERVICE PROCEDURE

How To Proceed With Troubleshooting

HINT:

  • Use these procedures to troubleshoot the defogger system.
  • *: Use the Techstream.
    1. VEHICLE BROUGHT TO WORKSHOP 
    2. INSPECT BATTERY VOLTAGE 

      Standard voltage: 

      11 to 14 V 

      If the voltage is below 11V, recharge or replace the battery before proceeding.

    3. INSPECT COMMUNICATION FUNCTION OF LARGE-SCALE MULTIPLEX COMMUNICATION SYSTEM (BEAN)* 
      1. Use the Techstream to check that the Multiplex Communication System (MPX) is functioning normally.

        Result 

        RESULT 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 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  4

    A : Go to Next Step 

  • OVERALL ANALYSIS AND TROUBLESHOOTING* 
    1. Terminals of ECU (see TERMINALS OF ECU  )
    2. Data List / Active Test (see DATA LIST / ACTIVE TEST  )
    3. On-vehicle Inspection (see ON-VEHICLE INSPECTION  )
    4. Inspection (see ON-VEHICLE INSPECTION  )
  • REPAIR OR REPLACE 
  • 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.