Mitsubishi Lancer Evolution X. Manual — part 29

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-141

DIAGNOSTIC ITEM 18: Diagnose when the scan tool cannot receive the data sent by occupant
classification-ECU.

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

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-142

.

FUNCTION

If the scan tool MB991958 cannot communicate with
the occupant classification-ECU, this diagnosis result
will be set.

.

TROUBLE JUDGMENT CONDITIONS

If a communication flag is not set for the occupant
classification-ECU, the ETACS-ECU determines that
there is a failure.

.

TROUBLESHOOTING HINTS

• Malfunction of the connector [joint connector

(CAN1), occupant classification-ECU connector
improperly connected]

• Malfunction of the wiring harness [open circuit

between the occupant classification-ECU con-
nector and the joint connector (CAN1), power
supply circuit to the occupant classification-ECU]

• Malfunction of the occupant classification-ECU

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set
• MB992006: Extra Fine Probe

STEP 1. Check joint connector (CAN1) C-105, occupant
classification-ECU connector D-39, D-39-2 and
intermediate connector C-41 for loose, corroded or
damaged terminals, or terminals pushed back in the
connector.

CAUTION

The strand end of the twisted wire should be within 10 cm
(4 inches) from the connector. For details refer to

P.54C-7

.

Q: Are joint connector (CAN1) C-105, occupant

classification-ECU connector D-39, D-39-2 and
intermediate connector C-41 in good condition?
YES : Go to Step 2.
NO : Repair the damaged parts.

AC708950CA

C-41

C-105

Connectors: C-41, C-105

AC708954 AV

Connectors: D-39, D-39-2

D-39,
D-39-2

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-143

STEP 2. Check the wiring harness between joint connector
(CAN1) C-105 and occupant classification-ECU connector
D-39-2 for open circuit.

CAUTION

Strictly observe the specified wiring harness repair proce-
dure. For details refer to

P.54C-7

.

(1) Disconnect joint connector (CAN1) C-105 and occupant

classification-ECU connector D-39-2, and check the wiring
harness.

(2) Check the wiring harness between joint connector (CAN1)

C-105 (terminal 11) and occupant classification-ECU
connector D-39-2 (terminal 24)

OK: Continuity exists (2 Ω or less)

(3) Check the wiring harness between joint connector (CAN1)

C-105 (terminal 24) and occupant classification-ECU
connector D-39-2 (terminal 25)

OK: Continuity exists (2 Ω or less)

Q: Is the wiring harness between joint connector (CAN1)

C-105 and occupant classification-ECU connector
D-39-2 in good condition?
YES : Check the power supply circuit of the occupant

classification-ECU. Refer to GROUP 52B, SRS air
bag Diagnosis

P.52B-383

.

NO : Repair the wiring harness between joint connector

(CAN1) C-105 and occupant classification-ECU
connector D-39-2.

AC709707

AC709707 CB

Harness side: C-105

Harness side: D-39-2

TEST HARNESS

TEST HARNESS

AC709707 CC

Harness side: C-105

Harness side: D-39-2

TEST HARNESS

TEST
HARNESS

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-144

DIAGNOSTIC ITEM 19: Diagnose when the scan tool cannot receive the data sent by A/C-ECU
<vehicles with A/C> or heater control unit <vehicles without A/C>.

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)