Mitsubishi Evolution X. Manual — part 1140

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-195

DIAGNOSTIC ITEM 27: Short to power supply or ground, open circuit or line-to-line short in the
CAN-B bus lines.

CAUTION

When servicing a CAN bus line, ground yourself by touching a metal object such as an unpainted
water pipe. If you fail to do so, a component connected to the CAN bus line may be damaged.

CAN-B Communication Circuit

ETACS-ECU

INTERFACE
CIRCUIT

CAN DRIVE
CIRCUIT

A/C-ECU

COMBINATION
METER

SRS-ECU

WIRELESS
CONTROL
MODULE

KOS-ECU

NOTE

VEHICLES WITH WCM
VEHICLES WITH KOS

CAN DRIVE
CIRCUIT

CAN DRIVE
CIRCUIT

CAN DRIVE
CIRCUIT

JOINT CONNECTOR
(CAN1)

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-196

CAN-B Communication Circuit

ETACS-ECU

INTERFACE
CIRCUIT

INTERFACE
CIRCUIT

CAN DRIVE
CIRCUIT

HANDS FREE
MODULE

OCCUPANT
CLASSIFICATION-
ECU

SATELLITE
RADIO
TUNER

RADIO AND CD
PLAYER

NOTE

VEHICLES WITHOUT MITSUBISHI MULTI-COMMUNICATION SYSTEM (MMCS)
VEHICLES WITH MITSUBISHI MULTI-COMMUNICATION SYSTEM (MMCS)

CAN
TRANSCEIVER
CIRCUIT

CAN BOX UNIT

JOINT CONNECTOR
(CAN1)

FRONT SEAT
ASSEMBLY (LH)

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-197

.

FUNCTION

If a short to power supply or ground, open circuit or
line-to-line short is present at either CAN_H or
CAN_L side on the CAN-B lines, this diagnosis result
will be set.

.

TROUBLE JUDGEMENT CONDITIONS

When CAN-B lines communication is normal, and
diagnostic trouble code U0019 is set, the
ETACS-ECU determines that there is a failure.

.

TROUBLESHOOTING HINTS

• Malfunction of the connector (short to power sup-

ply or ground in connector or improperly con-
nected)

• Malfunction of the wiring harness (short to power

supply or ground, open circuit or line-to-line short
in CAN bus lines)

• Faulty ECU(s) (internal short to power supply or

ground)

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set

• MB992006: Extra Fine Probe

AC608145

AO

Connectors: C-04, C-06, C-09, C-31, C-122

C-06

C-31

C-04

C-09

C-122 (Y)

AC608146

AE

C-17

C-108

Connectors: C-17, C-20, C-104, C-108, C-110

C-20 (B)

C-104

C-110

AC708950CF

C-05

C-41

C-105

Connectors: C-05, C-41, C-105

AC708951CF

Connectors: C-07, C-11, C-15, C-18, C-22,
C-37, C-107

C-07

C-15

C-18

C-22 (B)

C-11

C-37 (Y)

C-107

AC708972AY

Connector: C-301

ETACS-ECU

AC708954 AV

Connectors: D-39, D-39-2

D-39,
D-39-2

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-198

STEP 1. Check the wiring harness between ETACS-ECU
connector C-301 and body ground for a short to ground.
Measure the resistance at ETACS-ECU connector C-301.

CAUTION

Disconnect the negative battery terminal. For details refer
to

P.54C-7

.

CAUTION

A digital multimeter should be used. For details refer to

P.54C-7

.

CAUTION

The test wiring harness should be used. For details refer to

P.54C-7

.

(1) Disconnect ETACS-ECU connector C-301, and measure

the voltage at the wiring harness side of ETACS-ECU
connector.

(2) Measure the resistance between ETACS-ECU connector

terminal 6 and body ground.

OK: 1 kilo ohm or more

(3) Measure the resistance between ETACS-ECU connector

terminal 7 and body ground.

OK: 1 kilo ohm or more

Q: Do all the resistances measure 1 kilo ohm or more?

YES : Go to Step 2.
NO : Go to Step 13.

AC608179

TEST
HARNESS

Harness side: C-301

BL

AC608179

TEST
HARNESS

Harness side: C-301

BM