Mitsubishi Montero (2002-2004). Manual - part 246

SYMPTOM PROCEDURES

TSB Revision

SWS SYMPTOM PROCEDURES

54Bb-31

STEP 7. Check column switch connector D-203 and 
ETACS-ECU connector D-224 for loose, corroded or 
damaged terminals, or terminals pushed back in the 
connector.
Q: Are column switch connector D-203 and ETACS-ECU 

connector D-224 in good condition?
YES : Go to Step 8.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. The system should communicate with the 

ETACS-ECU normally.

STEP 8. Check the wiring harness between column switch 
connector D-203 (terminals 2 and 3) and ETACS-ECU 
connector D-224 (terminals 31 and 21).
Q: Is the wiring harness between column switch connector 

D-203 (terminals 2 and 3) and ETACS-ECU connector D-
224 (terminals 31 and 21) in good condition?
YES : Replace the ETACS-ECU. The system should 

communicate with the ETACS-ECU normally.

NO :  The wiring harness may be damaged or the 

connector(s) may have loose, corroded or damaged 
terminals, or terminals pushed back in the connector. 
Repair the wiring harness as necessary. The system 
should communicate with the ETACS-ECU normally.

AC204172

CONNECTOR : D-203

AC

HARNESS SIDE

1

2

3

7

8

6

5

10

4

9

D-203

AC204174

CONNECTOR : D-224

AD

D-224(B)

D-224(B)

HARNESS SIDE

21

23

24

22

32

3433

31

26

27

28

3029

38

39

40

36

37

25

35

AC204172

CONNECTOR : D-203

AC

HARNESS SIDE

1

2

3

7

8

6

5

10

4

9

D-203

AC204174

CONNECTOR : D-224

AD

D-224(B)

D-224(B)

HARNESS SIDE

21

23

24

22

32

3433

31

26

27

28

3029

38

39

40

36

37

25

35

SYMPTOM PROCEDURES

TSB Revision

SWS SYMPTOM PROCEDURES

54Bb-32

INSPECTION PROCEDURE A-4: Communication with the front-ECU is not possible.

NOTE: This troubleshooting procedure requires the 
use of scan tool MB991502 and SWS monitor kit 
MB991862. For details on how to use the SWS mon-
itor, refer to "How to use SWS monitor 

P.54Ba-8

."

Front-ECU Power Supply and SWS Communication Circuit

SYMPTOM PROCEDURES

TSB Revision

SWS SYMPTOM PROCEDURES

54Bb-33

.

CIRCUIT OPERATION

• The power supply to the front-ECU is provided by 

the battery and the ignition switch (IG2).

•  If the power supply system from the battery is 

defective, the system operates by the power sup-
ply from the ignition switch (IG2).

.

TECHNICAL DESCRIPTION (COMMENT)
It is suspected that the power supply circuit to the 
front-ECU is defective, or the wiring harness 
between the SWS monitor kit and the front-ECU or 
their connector(s) is damaged. If the battery power 
supply circuit to the ECU (terminal 7 of the front-
ECU) is damaged, also check the power supply cir-
cuit from the ignition switch (IG2) (terminal 30 of the 
front-ECU), and repair if necessary.

.

TROUBLESHOOTING HINTS

• The ETACS-ECU may be defective

• The front-ECU may be defective

• The wiring harness or connectors may have 

loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector

AC204183

CONNECTORS : A-07X, A-08X

A-08X

A-07X

AI

AC204170

CONNECTORS: D-02, D-28

BI

D-28

D-02

AC204174

CONNECTOR : D-224

D-224(B)

AG

SYMPTOM PROCEDURES

TSB Revision

SWS SYMPTOM PROCEDURES

54Bb-34

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set

• MB991502: Scan Tool (MUT-II) 

• MB991862: SWS monitor kit

STEP 1. Use scan tool MB991502 to select "ECU COMM 
CHK" on the SWS monitor display.
Check the ETACS-ECU.

CAUTION

To prevent damage to scan tool MB991502, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector 

(16-pin).

(2) Connect SWS monitor kit MB991862 to the data link 

connector (13-pin).

(3) Turn the ignition switch to the "LOCK" (OFF) position.
(4) Operate scan tool MB991502 according to the procedure 

below to display "ECU COMM CHK."

1. Select "SYSTEM SELECT."
2. Select "SWS."
3. Select "SWS MONITOR."
4. Select "ECU COMM CHK."

(5) Scan tool MB991502 should show "OK" on the "ECU 

COMM CHK" menu for the "ETACS ECU" menu.

Q: Is "OK" displayed on the "ETACS ECU" menu?

YES : Go to Step 2.
NO :  Refer to Inspection Procedure A-3 "Communication 

with ETACS-ECU is not possible 

P.54Bb-25

."

AC204222AB

16-pin

13-pin

MB991502

MB991862