DYNAMIC RADAR CRUISE CONTROL SYSTEM, Diagnostic DTC:U0235, U1104

DTC Code DTC Name
U0235 Lost Communication with Cruise Control Front Distance Range Sensor
U1104 Lost Communication with Driving Support ECU

DESCRIPTION

The driving support ECU assembly sends vehicle speed and vehicle condition information to the millimeter wave radar sensor assembly. The millimeter wave radar sensor assembly then sends information on the presence, distance, and relative speed of objects in front of the vehicle to the driving support ECU assembly. The driving support ECU assembly sends this information to the power management control ECU and the power management control ECU operates the dynamic radar cruise control system.

DTC No. DTC Detection Condition Trouble Area
U0235

    w/ Full-speed range following function:

  • While the vehicle speed is 5 km/h (3 mph) or more and the dynamic radar cruise control system is operating, a communication error between the millimeter wave radar sensor assembly and the driving support ECU assembly is detected for approximately 1 second


    w/o Full-speed range following function:

  • While the vehicle speed is 36 km/h (22 mph) or more and the dynamic radar cruise control system is operating, a communication error between the millimeter wave radar sensor assembly and the driving support ECU assembly is detected for approximately 1 second

  • CAN communication system

  • Millimeter wave radar sensor circuit

  • Driving support ECU assembly

  • Harness or connector
U1104

    w/ Full-speed range following function:

  • While the vehicle speed is 36 km/h (22 mph) or more and the dynamic radar cruise control system is operating, a communication error between the driving support ECU assembly and the millimeter wave radar sensor assembly is detected for approximately 1 second


    w/o Full-speed range following function:

  • While the vehicle speed is 36 km/h (22 mph) or more and the dynamic radar cruise control system is operating, a communication error between the millimeter wave radar sensor assembly and the driving support ECU assembly is detected for approximately 1 second

  • CAN communication system

  • Millimeter wave radar sensor circuit

  • Driving support ECU assembly

  • Harness or connector

WIRING DIAGRAM

B002BZLE07
*a from IG Circuit
*b Millimeter Wave Radar Sensor Assembly
*c Driving Support ECU Assembly
*d CAN Communication Line

CAUTION / NOTICE / HINT

Note


  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

  • When replacing the driving support ECU assembly, make sure to replace it with a new one. If a device which was installed to another vehicle is used, the information stored in the driving support ECU assembly will not match the information from the vehicle, and as a result, a DTC may be stored.

  • When the millimeter wave radar sensor is replaced with a new one, adjustment of the radar sensor beam axis must be performed Click here.

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Using the GTS, check that the CAN communication system is functioning normally.


      Result
      Result Proceed to
      CAN communication system DTCs are not output A
      CAN communication system DTCs are output (for LHD) B
      CAN communication system DTCs are output (for RHD) B

    B

    GO TO CAN COMMUNICATION SYSTEM Click here

    C

    GO TO CAN COMMUNICATION SYSTEM Click here

    A

  2. CHECK HARNESS AND CONNECTOR (DRIVING SUPPORT ECU ASSEMBLY POWER SOURCE)


    1. B002BMOE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Driving Support ECU Assembly)

      Disconnect the driving support ECU assembly connector.

    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      N173-28 (GND) - Body ground Always Below 1 Ω
      Standard Voltage
      Tester Connection Condition Specified Condition
      N173-7 (B) - Body ground Power switch on (IG) 11 to 14 V
      Power switch off Below 1 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (MILLIMETER WAVE RADAR SENSOR POWER SOURCE)


    1. B002C0KE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Millimeter Wave Radar Sensor Assembly)

      Disconnect the millimeter wave radar sensor assembly connector.

    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      B17-8 (IGB) - Body ground Power switch on (IG) 11 to 14 V
      Power switch off Below 1 V
      Standard Resistance
      Tester Connection Condition Specified Condition
      B17-1 (SGND) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (DRIVING SUPPORT ECU ASSEMBLY - MILLIMETER WAVE RADAR SENSOR)


    1. Disconnect the N173 driving support ECU assembly connector.

    2. Disconnect the B17 millimeter wave radar sensor assembly connector.

    3. Disconnect the Y17 forward recognition camera connector.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      N173-8 (CA1P) - B17-5 (CA1P) Always Below 1 Ω
      N173-9 (CA1N) - B17-6 (CA1N) Always Below 1 Ω
      N173-8 (CA1P) or B17-5 (CA1P) - Body ground Always 10 kΩ or higher
      N173-9 (CA1N) or B17-6 (CA1N) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY


    1. Replace the millimeter wave radar sensor assembly with a new one Click here.

    2. Perform millimeter wave radar sensor assembly adjustment Click here.


    NEXT

  6. CHECK FOR DTCs


    1. Clear the DTCs Click here.

    2. Make sure that the DTC detection conditions are met.

      Tech Tips

      If the detection conditions are not met, the system cannot detect the malfunction.


      1. Turn the power switch on (IG).

      2. Turn the dynamic radar cruise control system on using the cruise control main switch (ON/OFF).

      3. w/ Full-speed range following function: Drive the vehicle at 5 km/h (3 mph) or more for 1 second or more.

        w/o Full-speed range following function: Drive the vehicle at 36 km/h (22 mph) or more for 1 second or more.

    3. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC U0235 and U1104 are not output A
      DTC U0235 or U1104 is output B

    A

    END (MILLIMETER WAVE RADAR SENSOR ASSEMBLY WAS DEFECTIVE)

    B

    REPLACE DRIVING SUPPORT ECU ASSEMBLY Click here