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Inspection Procedure

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.
  1. INSPECT LASER SENSOR 
    1. Disconnect the laser sensor connector.
    2. Measure the voltage according to the value (s) in the table below.

      Standard: 

      TESTER CONNECTION CHART

      Tester connection Condition Specified value
      L1-5 (IGB) - Body ground Ignition SW ON 10 to 14 V
      Fig 1: Disconnecting Laser Sensor Connector
      G03513931Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: Go to step   3 . 
    2. OK: Go to next step. 
  2. CHECK WIRE HARNESS AND CONNECTOR 
    1. Disconnect the ECM E3 connector.
    2. Measure the resistance according to the value (s) in the table below.

      Standard: 

      TESTER CONNECTION CHART

      Tester connection Condition Specified value
      L1-1 (LGND) - E3-29 (LGND) Always Below 1Ω
      L1-1 (LGND) - Body ground Always 10 kΩ or higher
      L1-2 (SGND) - Body ground Always Below 1 Ω
      Fig 2: Identifying Wire Harness And Connector (Laser Sensor)
      G03513932Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 3: Identifying Wire Harness And Connector (ECM)
      G03513933Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE WIRE HARNESS OR CONNECTOR 
    2. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (See  PROBLEM SYMPTOMS TABLE  ) 
  3. CHECK WIRE HARNESS AND CONNECTOR (LASER SENSOR - DISTANCE CONTROL ECU) 
    1. Disconnect the cruise control ECU (distance control ECU) connector.
    2. Measure the resistance according to the value (s) in the table below.

      Standard: 

      TESTER CONNECTION CHART

      Tester connection Condition Specified value
      D2-13 (IGB) - L1-5 (IGB) Always Below 1 Ω
      D2-13 (IGB) - Body ground Always 10 kΩ or higher
      Fig 4: Checking Wire Harness And Connector (Laser Sensor)
      G03513934Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 5: Checking Wire Harness And Connector (Distance Control ECU)
      G03513935Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE WIRE HARNESS OR CONNECTOR 
    2. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (See  PROBLEM SYMPTOMS TABLE  )