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Millimeter Wave Radar Sensor Power Source Circuit: Procedure

  1. CHECK DISTANCE CONTROL ECU (IGB VOLTAGE) 
    Fig 1: Identifying Terminals Of Millimeter Wave Radar Sensor Connector
    GTY154017Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the millimeter wave radar sensor connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      B9-5 (IGB) - Body ground Engine switch on (IG) 11 to 14 V
    3. Disconnect the millimeter wave radar sensor connector.

    NG → See step   3 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (MILLIMETER WAVE RADAR SENSOR - ECM AND BODY GROUND) 
    Fig 2: Identifying Terminals Of Millimeter Wave Radar Sensor Connector
    GTY154016Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the millimeter wave radar sensor connector.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A5-16 (LGND) - B9-1 (LGND) Always Below 1 Ω
      B9-1 (LGND) - Body ground Always 10 kΩ or higher
      B9-2 (SGND) - Body ground Always Below 1 Ω
    4. Reconnect the millimeter wave radar sensor connector.
    5. Reconnect the ECM connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   4 

  3. CHECK HARNESS AND CONNECTOR (MILLIMETER WAVE RADAR SENSOR - DISTANCE CONTROL ECU) 
    1. Disconnect the millimeter wave radar sensor and distance control ECU connectors.
      Fig 3: Identifying Terminals Of Millimeter Wave Radar Sensor And Distance Control ECU Connectors
      GTY154013Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below

      Standard Resistance

      Tester Connection Condition Specified Condition
      B9-5 (IGB) - J17-13 (IGB) Always Below 1 Ω
      J17-13 (IGB) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   5 

  4. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE 
  5. REPLACE DISTANCE CONTROL ECU. Refer to  COMPONENTS