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Home >> Lexus >> 2013 >> IS 250C Base >> Repair and Diagnosis >> Accessories & Equipment >> Cruise Control Systems >> Dynamic Radar Cruise Control System (Diagnostic Codes & Circuit Tests) >> Dynamic Radar Cruise Control System >> DTC U0235: Lost Communication with Cruise Control Front Distance Range Sensor >> Procedure

DTC U0235: Lost Communication with Cruise Control Front Distance Range Sensor: Procedure

  1. CHECK HARNESS AND CONNECTOR (DISTANCE CONTROL ECU - MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 
    1. Disconnect the distance control ECU connector.
      GTY270995Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the millimeter wave radar sensor assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      J17-22 (LRDD) - B9-3 (LRDD) Always Below 1 Ω
      J17-13 (IGB) - B9-5 (IGB) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      J17-22 (LRDD) or B9-3 (LRDD) - Body ground Always 10 kΩ or higher
      J17-13 (IGB) or B9-5 (IGB) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Distance Control ECU)
      *2 Front view of wire harness connector
      (to Millimeter Wave Radar Sensor Assembly)
    4. Reconnect the distance control ECU connector.
    5. Reconnect the millimeter wave radar sensor assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (DISTANCE CONTROL ECU - MILLIMETER WAVE RADAR SENSOR ASSEMBLY) 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (MILLIMETER WAVE RADAR SENSOR ASSEMBLY - BODY GROUND) 
    1. Disconnect the millimeter wave radar sensor assembly connector.
      GTY267647Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      B9-2 (SGND) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Millimeter Wave Radar Sensor Assembly)
    3. Reconnect the millimeter wave radar sensor assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (MILLIMETER WAVE RADAR SENSOR ASSEMBLY - BODY GROUND) 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (DISTANCE CONTROL ECU - BODY GROUND) 
    1. Disconnect the distance control ECU connector.
      GTY275790Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      J17-10 (SGND) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Distance Control ECU)
    3. Reconnect the distance control ECU connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (DISTANCE CONTROL ECU - BODY GROUND) 

    OK: Go to next step 

  4. CHECK DISTANCE CONTROL ECU 
    1. Turn the engine switch on (IG).
      GTY264787Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      J17-13 (IGB) - J17-10 (SGND) Engine switch on (IG) 10 to 16 V
      J17-22 (LRDD) - J17-10 (SGND) Engine switch on (IG) 4.5 to 5.5 V
      TEXT IN ILLUSTRATION

      *1 Component with harness connected
      (Distance Control ECU)

    NG → See step   7 

    OK: Go to next step 

  5. REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY 
    1. Replace the millimeter wave radar sensor assembly. Refer to REMOVAL [08/2012 - ] .
    2. Adjust the millimeter wave radar sensor assembly. Refer to ADJUSTMENT [08/2012 - ] .

    NEXT: Go to next step 

  6. CHECK WHETHER DTC OUTPUT RECURS (DTC U0235) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Clear the DTCs. Refer to DTC CHECK/CLEAR [08/2012 - ] .
    5. Perform the following to make sure that the DTC detection conditions are met.

      HINT: 

      If the detection conditions are not met, the malfunction cannot be detected.

      1. Drive the vehicle at a speed of 50 km/h (30 mph) or more.
      2. Turn the cruise control main switch on.
    6. Enter the following menus: Powertrain / Radar Cruise / Trouble Codes.
    7. Read the DTCs. Refer to DTC CHECK/CLEAR [08/2012 - ] .

      Result

      Result Proceed to
      DTC is not output A
      DTC U0235 is output B

    B → See step   7 

    A → END 

  7. REPLACE DISTANCE CONTROL ECU. Refer to  REMOVAL [08/2012 - ]