PRE-CRASH SAFETY SYSTEM, Diagnostic DTC:U0122, U0123, U0126, U0140, U0151, U0235, U1002, U1100, U1104

DTC Code DTC Name
U0122 Lost Communication with Vehicle Dynamics Control Module
U0123 Lost Communication with Yaw Rate Sensor Module
U0126 Lost Communication with Steering Angle Sensor Module
U0140 Lost Communication with Main Body ECU
U0151 Lost Communication with Airbag ECU
U0235 Lost Communication with Cruise Control Front Distance Range Sensor
U1002 Lost Communication with Gateway Module
U1100 Lost Communication with Seat Belt Control ECU
U1104 Lost Communication with Driving Support ECU

DESCRIPTION

The driving support ECU uses the millimeter wave radar sensor to detect obstacles in front of the vehicle.

Based on this information, the driving support ECU sends pre-crash control operation signals.

These DTCs are stored when a communication malfunction occurs between the sensors and ECUs that detect collisions, or between ECUs that perform the pre-crash control.

DTC No. DTC Detection Condition Trouble Area
U0122

  • When the engine switch is on (IG), a communication error between the skid control ECU and the driving support ECU is detected for approximately 8 second.

  • When the engine switch is on (IG), a communication error between the skid control ECU and the seat belt control ECU is detected for approximately 3 second.

  • Skid control ECU

  • CAN communication system

  • Seat belt control ECU

  • Driving support ECU
U0123 When the engine switch is on (IG), a communication error between the yaw rate sensor and the driving support ECU is detected for approximately 4 second.

  • Yaw rate sensor

  • CAN communication system

  • Driving support ECU
U0126 When the engine switch is on (IG), a communication error between the steering sensor and the driving support ECU is detected for approximately 5 second.

  • Steering angle sensor

  • CAN communication system

  • Driving support ECU
U0140 While engine switch is on (IG), communication stop between main body ECU and seat belt control ECU continues for 6 second or more.

  • Main body ECU

  • CAN communication system

  • Seat belt control ECU
U0151 While engine switch is on (IG), communication stop between center airbag sensor and seat belt control ECU continues for 6 second or more.

  • Center airbag sensor

  • CAN communication system

  • Seat belt control ECU
U0235 When the engine switch is on (IG), a communication error between the millimeter wave radar sensor and the driving support ECU is detected for approximately 2 seconds.

  • CAN communication system

  • Millimeter wave radar sensor

  • Driving support ECU

  • Wire harness or connector
U1002 When the engine switch is on (IG), a communication error between the millimeter wave radar sensor and the driving support ECU is detected for approximately 2 seconds.

  • CAN communication system

  • Millimeter wave radar sensor

  • Driving support ECU

  • Wire harness or connector
U1100 When the engine switch is on (IG), a communication error between the seat belt control ECU and the driving support ECU is detected for approximately 10 second.

  • Seat belt control ECU

  • CAN communication system

  • Driving support ECU
U1104

  • When the engine switch is on (IG), a communication error between the driving support ECU and the millimeter wave radar sensor is detected for approximately 1 second.

  • When the engine switch is on (IG), a communication error between the driving support ECU and the seat belt control ECU is detected for approximately 1 second.

  • CAN communication system

  • Millimeter wave radar sensor

  • Driving support ECU

  • Seat belt control ECU

  • Wire harness or connector

WIRING DIAGRAM

A019PH4E08

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Select "CAN Bus Check" from the "System Selection Menu" screen on the intelligent tester.

    2. Select "Communication Malfunction DTC" from the "CAN Bus Check" screen, and then select "Enter".

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

    B

    GO TO CAN COMMUNICATION SYSTEM Click here

    A

  2. CHECK CAN COMMUNICATION SYSTEM


    1. Select "CAN Bus Check" from the "System Selection Menu" on the intelligent tester.

    2. Select "Communication Malfunction Check" from the "CAN Bus Check" screen, and then select "OK".

      OK
      CAN communication is normal.

    NG

    GO TO CAN COMMUNICATION SYSTEM Click here

    OK

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


    1. Disconnect the driving support ECU connector.

    2. Disconnect the millimeter wave radar sensor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      C1-40 (CA1P) - B1-4 (CA1P) Always Below 1 Ω
      C1-18 (CA1N) - B1-3 (CA1N) Always Below 1 Ω
      C1-40 (CA1P) or B1-4 (CA1P) - Body ground Always 10 kΩ or higher
      C1-18 (CA1N) or B1-3 (CA1N) - Body ground Always 10 kΩ or higher

    4. Reconnect the millimeter wave radar sensor connector.

    5. Reconnect the driving support ECU connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK TERMINAL VOLTAGE (POWER SOURCE OF DRIVING SUPPORT ECU)

    A019ONYE01
    Text in Illustration
    *1

    Front view of wire harness connector

    (to Driving Support ECU)

    1. Disconnect the driving support ECU connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      C1-30 (B) - Body ground Engine switch on (IG) 11 to 14 V
      C1-30 (B) - Body ground Engine switch off Below 1 V

    3. Reconnect the driving support ECU connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (DRIVING SUPPORT ECU - BODY GROUND)

    OK

  5. CHECK HARNESS AND CONNECTOR (DRIVING SUPPORT ECU - BODY GROUND)


    1. Disconnect the driving support ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      C1-25 (GND) - Body ground Always Below 1 Ω

    3. Reconnect the driving support ECU connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (DRIVING SUPPORT ECU - BODY GROUND)

    OK

  6. CHECK TERMINAL VOLTAGE (POWER SOURCE OF MILLIMETER WAVE RADAR SENSOR)

    A019NR0E09
    Text in Illustration
    *1

    Front view of wire harness connector

    (to Millimeter Wave Radar Sensor)

    1. Disconnect the millimeter wave radar sensor connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      B1-5 (IGB) - Body ground Engine switch on (IG) 11 to 14 V
      B1-5 (IGB) - Body ground Engine switch off Below 1 V

    3. Reconnect the millimeter wave radar sensor connector.


    NG

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

    OK

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


    1. Disconnect the millimeter wave radar sensor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B1-2 (SGND) - Body ground Always Below 1 Ω

    3. Reconnect the millimeter wave radar sensor connector.


    NG

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

    OK

  8. CHECK MILLIMETER WAVE RADAR SENSOR


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

    2. Perform millimeter wave radar sensor adjustment Click here.


    NEXT

  9. CHECK DTC OUTPUT


    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.

    3. Check for DTCs Click here.

      Note

      When replacing the driving support ECU, always replace it with a new one. If a driving support ECU which was installed to another vehicle is used, the information stored in the driving support ECU will not match the information from the vehicle. As a result, a DTC may be stored.

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

    B

    REPLACE DRIVING SUPPORT ECU Click here

    A

    END