DYNAMIC RADAR CRUISE CONTROL SYSTEM Millimeter Wave Radar Sensor Power Source Circuit

DESCRIPTION

This circuit provides power to the millimeter wave radar sensor. The millimeter wave radar sensor emits radio waves towards an object in front and measures the distance and direction of the object by receiving the beam reflections. Based on the reflections, the sensor calculates the difference in speed between the vehicle and the object in front. This data is transmitted to the distance control ECU. The ECU recognizes the millimeter wave radar sensor via terminals LGND. If an open circuit occurs in the wire harness between terminals LGND, the ECM cannot recognize the millimeter wave radar sensor. The ECM will stop the control of the vehicle-to-vehicle distance control mode and only the constant speed control mode can be used.

WIRING DIAGRAM

A015ZB9E01

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK DISTANCE CONTROL ECU (IGB VOLTAGE)

    A0162C5E01

    1. Disconnect the B9 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

    NG

    CHECK HARNESS AND CONNECTOR (MILLIMETER WAVE RADAR SENSOR - DISTANCE CONTROL ECU) Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (MILLIMETER WAVE RADAR SENSOR - ECM AND BODY GROUND)

    A015Z6FE01

    1. Disconnect the millimeter wave radar sensor connector.

    2. Disconnect the A5 connector from the ECM.

    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

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Click here

  3. CHECK HARNESS AND CONNECTOR (MILLIMETER WAVE RADAR SENSOR - DISTANCE CONTROL ECU)


    1. A01639UE03

      Disconnect the millimeter wave radar sensor and distance control ECU connectors.

    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

    REPLACE DISTANCE CONTROL ECU Click here