Mitsubishi Evolution X. Manual - part 112

54C-1

GROUP 54C

CONTROLLER 

AREA NETWORK 

(CAN)

CONTENTS

GENERAL INFORMATION . . . . . . . .

54C-2

STRUCTURE . . . . . . . . . . . . . . . . . . .

54C-3

SYSTEM OPERATION. . . . . . . . . . . .

54C-5

SELF-DIAGNOSIS  . . . . . . . . . . . . . . .

54C-8

CAN BUS DIAGNOSTICS  . . . . . . . . .

54C-8

GENERAL INFORMATION

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-2

GENERAL INFORMATION

M2542000100308

CAN, an abbreviation for Controller Area Network, is 
an ISO-certified international standard for a serial 
multiplex communication protocol

*

. A communication 

circuit employing the CAN protocol connects each 
ECU, and sensor data can be shared among, which 
enables more reduction in wiring.
NOTE: 

*

: The regulations have been decided in 

detail, from software matters such as the necessary 
transmission rate for communication, the system, 
data format, and communication timing control 
method to hardware matters such as the harness 
type and length and the resistance values.

CAN offers the following advantages.

• Transmission rates are much faster than those in 

conventional communication (up to 1 Mbps), 
allowing much more data to be sent.

• It is exceptionally immune to noise, and the data 

obtained from each error detection device is more 
reliable.

• Each ECU connected via the CAN communicates 

independently, therefore if the ECU enters dam-
aged mode, communications can be continued in 
some cases.

STRUCTURE

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-3

STRUCTURE

M2542000200695

• A gateway function has been integrated to 

ETACS-ECU as the network central ECU. (Refer 
to GROUP 54A, ETACS-ECU 

P.54A-39

.)

• The CAN system consists of the following three 

networks: CAN-B (middle-speed body network), 
CAN-C (high-speed power train network), and the 
diagnosis CAN-C (diagnosis exclusive network). 
Each ECU is connected to one of the networks 
depending on its functions.

• The CAN bus line consists of two lines, CAN_L 

and CAN_H (CAN Low and CAN High, respec-
tively), as well as two terminal resistors (A 
twisted-pair cable, highly resistant to noise, is 
used for the communications line).

• The CAN bus line connecting two dominant 

ECUs is the main bus line, and the CAN bus line 
connecting each ECU is the sub-bus line.

AC709105

ECM

SRS-ECU

A/C-ECU

CAN box 
unit

Satellite 
radio tuner

Hands free
module

Radio and 
CD player or 
CD changer

Combination 
meter

WCM OR 
KOS-ECU

Scan tool

Data link 
connector

ETACS-ECU

ASC-ECU

CAN_H

CAN_L

Main bus line

CAN_H

CAN_L

CAN_H

CAN_L

CAN-C

CAN-B

Diagnosis CAN-C

AB

Terminal resistor

Terminal 
resistor

: Indicates main bus line

: Indicates sub bus line

Occupant
classification-
ECU

Main bus line

TC-SST-
ECU

Shift lever

S-AWC-
ECU

Steering
wheel
sensor

STRUCTURE

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-4

• With CAN-C, the terminal resistors are incorpo-

rated in ECU. Resistors with approximately 120 
ohms is used for the dominant ECU, and that with 
3.0 kiloohms is used for the non-dominant ECU.
NOTE: 

.

•

Dominant ECU: ETACS-ECU and engine 
ECU

•

Non-dominant ECU: ECU and sensor on 
CAN-C network, excluding ETACS-ECU and 
engine ECU

• To the CAN bus line, ECU, sensor, and data link 

connector are connected as follows for each net-
work.
CAN-B

• Wireless control module (WCM) <vehicles 

without KOS>

• KOS-ECU <vehicles with KOS>

• SRS-ECU

• Occupant classification-ECU

• A/C-ECU

• Radio and CD player or CD changer <vehi-

cles without Mitsubishi Multi-Communication 
System (MMCS)>

• CAN box unit <vehicles with Mitsubishi 

Multi-Communication System (MMCS)>

• Hands free module <vehicles with hands-free 

system>

• Satellite radio tuner <vehicles with satellite 

radio>

• Combination meter

CAN-C

• ASC-ECU

• TC-SST-ECU <TC-SST>

• Shift lever <TC-SST>

• S-AWC-ECU

• Steering wheel sensor

• Engine control module (ECM)

Diagnosis CAN-C

• Data link connector