2008 Lexus IS FFACTORY OEM SERVICE PROCEDURE

Inspection Procedure

NOTE:
  • When the power window regulator motor assembly (applicable location) connector, the multiplex network master switch assembly connector or the multiplex network switch assembly (applicable location) connector is disconnected, the power window control system must be initialized (See CUSTOMIZE PARAMETERS  ).
  • Since the power window control system has functions that use multiplex communication (BEAN), first confirm that there is no malfunction in the multiplex communication system by inspecting the multiplex communication functions in accordance with the How to Proceed with Troubleshooting procedure (See HOW TO PROCEED WITH TROUBLESHOOTING  ). Then, conduct the following inspection procedure.
  1. PERFORM INITIALIZATION (POWER WINDOW CONTROL SYSTEM (APPLICABLE LOCATION)) 
    1. Initialize the power window control system (applicable location) (See CUSTOMIZE PARAMETERS  ).
  2. CHECK POWER WINDOW CONTROL SYSTEM (AUTO UP/DOWN FUNCTION) 
    1. Check that the power window operates normally by opening and closing the window (See OPERATION CHECK  ).

      OK: AUTO UP/DOWN function operates normally. 

    NG: Go to step 3 

    OK: END (INITIALIZATION IS DEFECTIVE) 

  3. CHECK WINDOW GLASS SLIDING MOVEMENT (APPLICABLE LOCATION) 
    1. Remove the window regulator.
    2. Install the window glass onto the door glass run
    3. Check if the door window regulator operates smoothly.
    4. Check that the window glass slides smoothly when sliding it up by hand

      OK: Door window glass slides smoothly. 

      HINT.

      Ensure the following.

      • The window glass fits with the glass run without improper contact.
      • Neither deformation nor foreign objects are in the glass run
      CAUTION: Perform initialization again.

      Result 

      RESULT REFERENCE

      Result Proceed to
      OK (Driver side window) A
      OK (Front passenger side window) B
      OK (Rear LH side window) C
      OK (Rear RH side window) D
      NG E

    A: REPLACE MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY  (See REMOVAL  )

    B: REPLACE MULTIPLEX NETWORK SWITCH ASSEMBLY (for Front Passenger Side)  (See REMOVAL  )

    C: REPLACE MULTIPLEX NETWORK SWITCH ASSEMBLY (for Rear LH Side)  (See REMOVAL  )

    D: REPLACE MULTIPLEX NETWORK SWITCH ASSEMBLY (for Rear RH Side)  (See REMOVAL  )

    E: FIT WINDOW GLASS CORRECTLY (REMOVE FOREIGN OBJECTS CAUSING IMPROPER FITTING OR REPLACE PARTS) 

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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