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Inspection Procedure

  1. CHECK DISTANCE CONTROL ECU (IGB VOLTAGE SIGNAL) 
    1. Disconnect the B8 sensor connector.
    2. Measure the voltage of the wire harness side connector.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      B8-5 (IGB) - Body ground Power switch ON (IG) 10 to 14 V
      Fig 1: Identifying B8 Sensor Connector Terminals
      G05306738Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG:  GO TO step  3

    OK: GO TO Next Step 

  2. CHECK WIRE HARNESS (MILLIMETER WAVE RADAR SENSOR - HYBRID VEHICLE CONTROL ECU) 
    1. Disconnect the B8 sensor connector.
    2. Disconnect the A54 ECU connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      B8-1 (LGND) - A54-1 (LGND) Below 1 Ω
      B8-1 (LGND) - Body ground 10 kΩ or higher
      Fig 2: Identifying B8 Sensor And A54 ECU Connector Terminals
      G05306739Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  

  3. CHECK WIRE HARNESS (MILLIMETER WAVE RADAR SENSOR - DISTANCE CONTROL ECU) 
    1. Disconnect the B8 sensor connector.
    2. Disconnect the K13 ECU connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      B8-5 (IGB) - K13-13 (IGB) Below 1 Ω
      B8-5 (IGB) - Body ground 10 kΩ or higher
      Fig 3: Identifying B8 Sensor And K13 ECU Connector Terminals
      G05306740Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE