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
U2154	87	CAN comm err (MIU) [Controller area network communication error (Multimedia interface unit)]	Diagnosis condition	READY indicator: ON When FCM 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 “U2154-87” is detected, first diagnose the CAN communication system.

POSSIBLE CAUSE

CAN communication system

FAIL-SAFE

None

CONFIRMATION PROCEDURE

1.PERFORM DTC CONFIRMATION PROCEDURE

Change the power supply mode of the electric motor switch to ON (READY indicator: ON).
Turn the FCM system ON.
Perform “Read All DTCs” with M.U.T.-III SE.
Check if the “U2154-87” is detected as the current malfunction in "Diagnostic Trouble Code" of “ICC/ADAS 2”.

Is “U2154-87” 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