LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2008 >> IS 350 >> Repair and Diagnosis >> Body & Frame >> Windows >> Windshield/WINDOWGLASS >> Power Window Control System >> Diagnosis System
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnosis System

  1. DESCRIPTION 
    1. Data of the system can be read from the Data Link Connector 3 (DLC3) of the vehicle. Therefore, when the system seems to be malfunctioning, use the Techstream to check for a malfunction and repair it.
  2. CHECK DLC3 
    1. The vehicle's ECM uses ISO 9141-2 communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.
      Fig 1: Identifying DLC3 Connector Terminals
      G05274332Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard 

      DLC3 TERMINALS REFERENCE

      Tester Connection Condition Specified Condition
      7 (Bus + line) - 5 (Signal ground) During communication Pulse generation
      4 (Chassis ground) - Body ground Always Below 1 Ω
      5 (Signal ground) - Body ground Always Below 1 Ω
      16 (B+) - Body ground Always 9 to 14 V

      HINT:

      If the screen displays a communication error message after you have connected the cable of the Techstream to the DLC3, turned the engine switch on (IG) and used the Techstream, the problem may be on the vehicle side or tester side.

      • If communication is normal when the tester is connected to another vehicle, inspect the DLC3 of the original vehicle.
      • If communication is still impossible when the tester is connected to another vehicle, the problem is probably in the tester itself, so consult the Service Department listed in the tester's instruction manual.
  3. INSPECT BATTERY VOLTAGE 
    1. Check the battery voltage.

      Standard voltage: 

      11 to 14 V 

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

  4. CHECK DIAGNOSIS 

    HINT:

    If there is a malfunction in the pulse sensor, manually operating the power window switch will cause the power window switch light to blink. The light continues to blink for 43 seconds or until the engine switch is turned off.

    After 43 seconds, the power window switch light remains on.

    1. Turn the engine switch on (IG).
    2. Manually operate the power window master switch or power window switch at each door.
    3. Check the blinking pattern of the AUTO light as shown in the illustration.
      Fig 2: Identifying Power Window Switches
      G05006550Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 3: Identifying Blinking Pattern Of Auto Light
      G05205071Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. If pattern (A) is displayed, reset the power window regulator motor.
      2. If pattern (B) or (C) is displayed, check the wire harness.
      3. If the normal pattern is displayed, replace the multiplex network master switch.