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Inspection Procedure

NOTE:
  • When the distance control ECU is replaced with a new one, initialization must be performed (See INSTALLATION  ).
  • When the millimeter wave radar sensor is replaced with a new one, adjustment of the radar sensor beam axis must be performed (See ADJUSTMENT  ).
  1. CHECK HARNESS AND CONNECTOR (DISTANCE CONTROL ECU - MILLIMETER WAVE RADAR SENSOR) 
    1. Disconnect the distance control ECU and millimeter wave radar sensor connectors.
    2. Measure the resistance according to the value (s) in the table below

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      J17-23 (LRRD) - B9-4 (LRRD) Always Below 1 Ω
      J17-13 (IGB) - B9-5 (IGB) Always Below 1 Ω
      J17-23 (LRRD) - Body ground Always 10 kΩ or higher
      J17-13 (IGB) - Body ground Always 10 kΩ or higher
    3. Fig 1: Identifying Terminals Of Distance Control ECU And Millimeter Wave Radar Sensor Connectors
      G05750621Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  2. REPLACE DISTANCE CONTROL ECU 
    1. Replace the distance control ECU (See DISTANCE CONTROL ECU  ).
    2. Initialize the distance control ECU (See INSTALLATION  ).
  3. CHECK DTC 
    1. Clear the DTC (See DTC CHECK / CLEAR  ).
    2. Turn the cruise control main switch on
    3. Drive the vehicle at the require speed (45 km/h (27 mph) or higher)
    4. Check if the same DTC is recorded (See DTC CHECK / CLEAR  ).

      Result 

      RESULT REFERENCE

      Result Proceed to
      DTC U1102 is not output A
      DTC U1102 is output B

    B: REPLACE MILLIMETER WAVE RADAR SENSOR  (See MILLIMETER WAVE RADAR SENSOR  )

    A: END