PRE-CRASH SAFETY SYSTEM, Diagnostic DTC:U0122, U0123, U0126, U0140, U0151, U0293, U1100, U1104

DTC Code	DTC Name
U0122	Lost Communication with Vehicle Dynamics Control Module
U0123	Communication Error of Yaw Rate Sensor
U0126	Lost Communication with Steering Angle Sensor Module
U0140	Lost Communication with Main Body ECU
U0151	Lost Communication with Airbag ECU
U0293	Lost Communication with HV ECU
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 assembly 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.
The driving support ECU 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 ahead to the driving support ECU. The driving support ECU sends this information to the ECM and performs pre-crash safety system (DTC U1104).

DTC No.	DTC Detection Condition	Trouble Area
U0122	When the power switch is on (IG), a communication error between the skid control ECU assembly and the driving support ECU is detected for approximately 5 seconds. When the power switch is on (IG), a communication error between the skid control ECU assembly and the seat belt control ECU is detected for approximately 1 second.	Skid control ECU assembly CAN communication system Seat belt control ECU Driving support ECU
U0123	When the power switch is on (IG), a communication error between the yaw rate sensor and the driving support ECU is detected for approximately 1 second.	Yaw rate sensor CAN communication system Driving support ECU
U0126	When the power switch is on (IG), a communication error between the steering sensor and the driving support ECU is detected for approximately 4 seconds.	Steering angle sensor CAN communication system Driving support ECU
U0140	While the power switch is on (IG), communication stop between the main body ECU and seat belt control ECU continues for 1 second or more.	Main body ECU CAN communication system Seat belt control ECU
U0151	While the power switch is on (IG), communication stop between the center airbag sensor and seat belt control ECU continues for 1 second or more.	Center airbag sensor CAN communication system Seat belt control ECU
U0293	When the power switch is on (IG), a communication error between the power management control ECU and skid control ECU assembly is detected for approximately 1 second. When the power switch is on (IG), a communication error between the power management control ECU and driving support ECU is detected for approximately 4 seconds.	Power management control ECU Skid control ECU assembly CAN communication system Driving support ECU
U1100	When the power switch is on (IG), a communication error between the seat belt control ECU and the driving support ECU is detected for approximately 9 seconds.	Seat belt control ECU CAN communication system Driving support ECU
U1104	When the power switch is on (IG), a communication error between the driving support ECU and the seat belt control ECU is detected for approximately 1 second. When the power switch is on (IG), a communication error between the driving support ECU and the power management control ECU is detected for approximately 1 second.	Communication circuit Seat belt control ECU Driving support ECU Power management control ECU CAN communication system

INSPECTION PROCEDURE

PROCEDURE

CHECK FOR DTC (RADAR CRUISE)

Connect the intelligent tester to the DLC3.
Turn the power switch on (IG).
Turn the intelligent tester on.
Enter the following menus: Powertrain / Radar Cruise / Trouble Codes.
Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

Read the DTCs.

Result

Result	Proceed to
CAN communication system DTCs are not output	A
CAN communication system DTCs are output	B

GO TO CAN COMMUNICATION SYSTEM Click here

USE SIMULATION METHOD TO CHECK Click here