DTC    U0122    Lost Communication with Vehicle Dynamics Control Module

DTC    U0123    Lost Communication with Yaw Rate Sensor Module

DTC    U0126    Lost Communication with Steering Angle Sensor Module

DTC    U0293    Lost Communication with HV ECU

DTC    U1104    Lost Communication with Driving Support ECU

for Preparation Click here


DESCRIPTION

These DTCs are stored when a communication malfunction occurs between the sensors and ECUs.

DTC No.
DTC Detection Condition
Trouble Area
U0122
While dynamic radar cruise control is either preparing for operation or operating and power switch is on (IG), communication stop between skid control ECU and driving support ECU assembly continues for 1 second or more
  1. Brake booster with master cylinder (skid control ECU)
  2. CAN communication system
  3. Driving support ECU assembly
U0123
While dynamic radar cruise control is either preparing for operation or operating and power switch is on (IG), communication stop between yaw rate sensor and driving support ECU assembly continues for 1 second or more
  1. Yaw rate sensor
  2. CAN communication system
  3. Driving support ECU assembly
U0126
While dynamic radar cruise control is either preparing for operation or operating and power switch is on (IG), communication stop between steering angle sensor and driving support ECU assembly continues for 1 second or more
  1. Steering angle sensor
  2. CAN communication system
  3. Driving support ECU assembly
U0293
While dynamic radar cruise control is either preparing for operation or operating and power switch is on (IG), communication stop between power management control ECU and driving support ECU assembly or skid control ECU continues for 1 second or more
  1. Power management control ECU
  2. CAN communication system
  3. Driving support ECU assembly
  4. Brake booster with master cylinder (skid control ECU)
U1104
While dynamic radar cruise control is either preparing for operation or operating and power switch is on (IG), communication stop between driving support ECU assembly and millimeter wave radar sensor assembly, power management control ECU, or brake booster with master cylinder (skid control ECU) continues for 1 second or more
  1. Driving support ECU assembly
  2. CAN communication system
  3. Millimeter wave radar sensor assembly
  4. Power management control ECU
  5. Brake booster with master cylinder (skid control ECU)

WIRING DIAGRAM

Refer to System Diagram (Click here).
Refer to U0235 (Click here).

INSPECTION PROCEDURE

1.READ OUTPUT DTC

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Turn the tester on.

  1. Enter the following menus: Powertrain / Radar Cruise / DTC.

  1. Enter the following menus: Powertrain / Hybrid Control / DTC.

  1. Read the DTCs.

    Result:
    Result
    		Proceed to
    DTC U1104 is output (for Radar Cruise)
    		A
    DTC U1104 is output (for Hybrid Control)
    		B
    DTCs other than U1104 are output
    		B



B
GO TO CAN COMMUNICATION SYSTEM (Click here)
A


2.CHECK CAN COMMUNICATION SYSTEM

  1. Using the intelligent tester to check if the CAN communication system is functioning normally (Click here).

    Result 
    Result
    		Proceed to
    CAN communication is normal
    		A
    CAN communication is malfunctioning
    		B



B
GO TO CAN COMMUNICATION SYSTEM (Click here)
A


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

  1. Disconnect the driving support ECU assembly and millimeter wave radar sensor assembly connectors.

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

    Standard Resistance (Check for Open):
    Tester Connection
    		Condition
    		Specified Condition
    H5-38 (LRRD) - A2-4 (LRRD)
    		Always
    		Below 1 Ω

    Standard Resistance (Check for Short):
    Tester Connection
    		Condition
    		Specified Condition
    H5-38 (LRRD) or A2-4 (LRRD) - Body ground
    		Always
    		10 kΩ or higher

  1. Reconnect the driving support ECU assembly and millimeter wave radar sensor assembly connectors.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (DRIVING SUPPORT ECU - MILLIMETER WAVE RADAR SENSOR ASSEMBLY)
OK


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


    E178930E55

  1. Disconnect the driving support ECU assembly connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    H5-25 (GND) - Body ground
    		Always
    		Below 1 Ω

    Text in Illustration 
    *a
    		Front view of wire harness connector
    (to Driving Support ECU Assembly)

  1. Reconnect the driving support ECU assembly connector.



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


5.REPLACE DRIVING SUPPORT ECU ASSEMBLY

  1. Replace the driving support control ECU assembly (Click here).


NEXT


6.CHECK WHETHER DTC OUTPUT RECURS (DTC U1104)

  1. Connect the intelligent tester to DLC3.

  1. Turn the power switch on (IG).

  1. Clear the DTCs (Click here).

  1. 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) and 170 km/h (105 mph).

    2. Turn the cruise control switch (ON-OFF button) on.

    3. Push the -/SET switch to activate the cruise control.

  1. Enter the following menus: Powertrain / Radar Cruise / DTC.

  1. Read the DTCs.

Result:
Result
Proceed to
DTC is not output
A
DTC U1104 is output
B



B
REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY (Click here)
A

END