DTC Description

CAN COMMUNICATION

CAN (Controller Area Network) is a serial communication line for real time applications. It is an on-vehicle multiplex communication line with high data communication speed and excellent error detection ability. Modern vehicle is equipped with many electronic control units, and each control unit shares information and links with other control units during operation (not independent). In CAN communication, control units are connected with 2 communication lines (CAN-H, CAN-L) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads the required data only.

CAN communication signal chart. Refer to CAN Communication Signal Chart

DTC DETECTION LOGIC

DTC		M.U.T.-III SE screen terms (Trouble diagnosis content)	DTC detection condition
U226B	87	CAN comm err (front camera) [Controller area network communication error (front camera)]	Diagnosis condition	When engine is running When AEB system is ON
			Signal (terminal)	CAN communication signal
			Threshold	If ADAS control unit 2 is not transmitting or receiving CAN communication signal
			Diagnosis delay time	2 seconds or more

note	If “U226B-87” is detected, first diagnose the CAN communication system.

POSSIBLE CAUSE

CAN communication system

FAIL-SAFE

The following systems are canceled.

Vehicle-to-vehicle distance control mode
Conventional (fixed speed) cruise control mode
Steering wheel assistance function
AEB
LDW
LDP
Active Blind Spot Assist [ABSA]
TSR

note	With the detection of “U226B-87” some systems do not perform the fail-safe operation. A system controlling based on a signal received from the control unit performs fail-safe operation when the communication with the ADAS control unit 2 becomes inoperable.

CONFIRMATION PROCEDURE

1.PERFORM DTC CONFIRMATION PROCEDURE

Start the engine.
Turn the AEB system ON.
Perform “Read All DTCs” with M.U.T.-III SE.
Check if the “U226B-87” is detected as the current malfunction in “Self Diagnostic Result” of “ACC/ADAS 2”.

Is “U226B-87” detected as the current malfunction?

Refer to DTC Diagnosis ProcedureDiagnosis Procedure

-1 To check malfunction symptom before repair: Refer to Intermittent IncidentIntermittent Incident

-2 Confirmation after repair: INSPECTION END