Mitsubishi Evolution X. Manual - part 1122

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-123

STEP 2. Check the wiring harness between joint connector 
(CAN3) C-127 and joint connector (CAN4) A-14 for open 
circuit.

CAUTION

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

P.54C-7

.

(1) Disconnect joint connector (CAN3) C-127 and joint 

connector (CAN4) A-14, and check the wiring harness.

(2) Check the wiring harness between joint connector (CAN3) 

C-127 (terminal 3) and joint connector (CAN4) A-14 
(terminal 5)

OK: Continuity exists (2 

Ω or less)

(3) Check the wiring harness between joint connector (CAN3) 

C-127 (terminal 14) and joint connector (CAN4) A-14 
(terminal 16)

OK: Continuity exists (2 

Ω or less)

Q: Is the wiring harness between joint connector (CAN3) 

C-127 and joint connector (CAN4) A-14 in good 
condition?
YES : The trouble can be an intermittent malfunction (Refer 

to GROUP 00, How to use 
Troubleshooting/inspection Service Points 

− How to 

Cope with Intermittent Malfunction 

P.00-15

).

NO :  Repair the wiring harness between joint connector 

(CAN3) C-127 and joint connector (CAN4) A-14.

AC709707BT

TEST 
HARNESS

Harness side: A-14

TEST 
HARNESS

Harness side: C-127

AC709707BU

Harness side: A-14

Harness side: C-127

TEST HARNESS

TEST 
HARNESS

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-124

DIAGNOSTIC ITEM 15: Diagnose when the scan tool cannot receive the data sent by KOS-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

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-125

.

FUNCTION

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

.

TROUBLE JUDGEMENT CONDITIONS

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

.

TROUBLESHOOTING HINTS

• Malfunction of the connector [joint connector 

(CAN1), KOS-ECU connector improperly con-
nected]

• Malfunction of the wiring harness [open circuit 

between the KOS-ECU connector and the joint 
connector (CAN1), power supply circuit to the 
KOS-ECU]

• Malfunction of the KOS-ECU

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set

• MB992006: Extra Fine Probe

STEP 1. Check joint connector (CAN1) C-105 and 
KOS-ECU connector C-05 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 and KOS-ECU 

connector C-05 in good condition?
YES : Go to Step 2.
NO :  Repair the damaged parts.

AC708950BZ

C-05

C-105

Connectors: C-05, C-105

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-126

STEP 2. Check the wiring harness between joint connector 
(CAN1) C-105 and KOS-ECU connector C-05 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 KOS-ECU 

connector C-05, and check the wiring harness.

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

C-105 (terminal 9) and KOS-ECU connector C-05 (terminal 
1)

OK: Continuity exists (2 

Ω or less)

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

C-105 (terminal 22) and KOS-ECU connector C-05 
(terminal 2)

OK: Continuity exists (2 

Ω or less)

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

C-105 and KOS-ECU connector C-05 in good condition?
YES : Check the power supply circuit of the KOS-ECU. 

Refer to GROUP 42B, KOS-ECU 

− Diagnosis 

P.42B-172

.

NO :  Repair the wiring harness between joint connector 

(CAN1) C-105 and KOS-ECU connector C-05.

AC709707

AC709707 BV

TEST HARNESS

Harness side: C-105

TEST HARNESS

Harness side: C-05

AC709707 BW

Harness side: C-105

TEST HARNESS

Harness side: C-05

TEST 
HARNESS