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 No.	M.U.T.-III SE screen terms (Trouble diagnosis content)	DTC detection condition
U2148-87	CAN comm err (brake control unit) [Controller area network communication error (brake control unit)]	Diagnosis condition	When electric motor switch is ON
		Signal (terminal)	–
		Threshold	If side radar LH is not transmitting or receiving CAN communication signal
		Diagnosis delay time	2 seconds or more

POSSIBLE CAUSE

CAN communication system

FAIL-SAFE

The following systems are canceled.

BSW
Active Blind Spot Assist [ABSA]
RCTA

CONFIRMATION PROCEDURE

1.PERFORM DTC CONFIRMATION PROCEDURE

Change the power supply mode of the electric motor switch to ON (READY indicator: ON).
Perform “Read All DTCs” with M.U.T.-III SE.
Check if the “U2148-87” is detected as the current malfunction in "Diagnostic Trouble Code" of “Side radar (Rear left)”.

Is “U2148-87” 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