Mitsubishi Montero (2004+). Manual - part 744

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-233

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827: MUT-III USB Cable

• MB991911: MUT-III Main Harness B

• MB991813: SWS Monitor Kit

• MB991806: SWS Monitor Cartridge

• MB991812: SWS Monitor Harness (For Column-ECU)

• MB991822: Probe Harness

STEP 1. Use scan tool MB991958 to select "ECU COMM 
CHK" on the SWS monitor display.
Check the following ECUs:

• Column-ECU

• Front-ECU

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "lock" (OFF) position before con-
necting or disconnecting scan tool MB991958. 
(1) Connect the special tool. Refer to "How to connect SWS 

monitor 

P.54B-7

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

connector (13-pin).

(3) Turn the ignition switch to the "ON" position.
(4) Operate scan tool MB991958 according to the procedure 

below to display "ECU COMM CHECK."

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

(5) Scan tool MB991958 should show "OK" on the "ECU 

COMM CHK" menus for both the "COLUMN ECU" and the 
"FRONT ECU" menus.

Q: Is "OK" displayed on the "COLUMN ECU" and "FRONT 

ECU" menu?
"OK" is displayed for all the items : Go to Step 2.
"NG" is displayed on the "COLUMN ECU" menu : Refer 

to Inspection Procedure A-2 "Communication with 
column switch (column-ECU) is not possible 

P.54B-35

."

"NG" is displayed on the "FRONT ECU" menu : Refer to 

Inspection procedure A-4 "Communication with 
front-ECU is not possible 

P.54B-48

."

AC309091

MB991911

MB991827

MB991824 

AB

MB991806

MB991862

DATA LINK
CONNECTOR 
(16-PIN)

DATA LINK
CONNECTOR 
(13-PIN)

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-234

STEP 2. Check the input signal by using "FUNCTION 
DIAG." menu of the SWS monitor.
Check the input signals from the following switches:

• Ignition switch: ACC

• Windshield wiper switch: INT

Operate the scan tool according to the procedure below to dis-
play "F.WIPER INT."

1. Select "SYSTEM SELECT."
2. Select "SWS."
3. Select "SWS MONITOR."
4. Select "FUNCTION DIAG."
5. Select "WIPER."
6. Select "F.WIPER INT."

Check that normal conditions are displayed on the items 
described in the table below.

Q: Are normal conditions displayed for "INT WIPER SW" 

and "FRONT ECU ACK"?
Normal conditions displayed for all the items : Go to 

Step 3.

The scan tool does not show the respective normal 
condition for item "INT WIPER SW" : Replace the column 

switch. Verify that the windshield wiper works 
normally.

The scan tool does not show the respective normal 
condition for item "FRONT ECU ACK" : Replace the 

front-ECU. Verify that the windshield wiper works 
normally.

STEP 3. Check windshield wiper motor connector B-12 for 
loose, corroded or damaged terminals, or terminals 
pushed back in the connector.
Q: Is windshield wiper motor connector B-12 in good 

condition?
YES : Go to Step 4.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. Verify that the windshield wiper works 

normally.

ITEM NO.

ITEM NAME

NORMAL 
CONDITION

ITEM 05

INT WIPER SW

ON

ITEM 70

FRONT ECU 
ACK

NORMAL ACK or 
HI-BEAM ACK

AC309091

MB991911

MB991827

MB991824 

AB

MB991806

MB991862

DATA LINK
CONNECTOR 
(16-PIN)

DATA LINK
CONNECTOR 
(13-PIN)

AC205116 AD

CONNECTOR: B-12

B-12 (B)

(HARNESS SIDE)

B-12 (B)

1

2

3

4

5

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-235

STEP 4. Check the windshield wiper motor.
(1) Disconnect windshield wiper motor connector B-12.
(2) Connect a battery to the windshield wiper motor as shown. 

Then check the windshield wiper motor operates normally 
at high and low speeds.

Q: Does the windshield wiper motor operate normally?

YES : Go to Step 5.
NO :  Replace the windshield wiper motor. Verify that the 

windshield wiper works normally.

STEP 5. Check the ground circuit to the windshield wiper 
motor. Test at windshield wiper motor connector B-12.
(1) Disconnect windshield wiper motor connector B-12 and 

measure the resistance available at the wiring harness side 
of the connector.

(2) Measure the resistance value between terminal 5 and 

ground.

• The resistance should equal 2 ohms or less.

Q:  Is the measured resistance 2 ohms or less?

YES : Go to Step 7.
NO :  Go to Step 6.

1

2 3

4

5

1

2 3

4

5

ACX02403

B-12

AB

LOW-SPEED

HIGH-SPEED

AC205116 AD

CONNECTOR: B-12

B-12 (B)

(HARNESS SIDE)

B-12 (B)

1

2

3

4

5

1

2

3

4

5

ACX01576AB

CONNECTOR B-12
(HARNESS SIDE)

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-236

STEP 6. Check the wiring harness between windshield 
wiper motor connector B-12 (terminal 5) and ground.
Q: Is the wiring harness between windshield wiper motor 

connector B-12 (terminal 5) and ground in good 
condition?
YES : No action is necessary and testing is complete.
NO :  The wiring harness may be damaged or the connector 

may have loose, corroded or damaged terminals, or 
terminals pushed back in the connector. Repair the 
wiring harness as necessary. Verify that the 
windshield wiper works normally.

STEP 7. Check front-ECU connector A-08X for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.
Q: Is front-ECU connector A-08X 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

. Verify that the windshield wiper works 

normally.

STEP 8. Check the ignition switch (ACC) circuit to the 
front-ECU. Test at front-ECU connector A-08X.
(1) Disconnect front-ECU connector A-08X, and measure at 

the relay box side.

(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal 24 and ground.

• The voltage should be approximately 12 volts (battery 

positive voltage).

Q: Is the measured voltage approximately 12 volts (battery 

positive voltage)?
YES : Go to Step 10.
NO :  Go to Step 9.

AC205116 AD

CONNECTOR: B-12

B-12 (B)

(HARNESS SIDE)

B-12 (B)

1

2

3

4

5

AC204183

CONNECTOR : A-08X

AC

22

23

21

26 25

27

28

31 30 29

24

RELAY BOX SIDE

A-08X

AC204183

CONNECTOR : A-08X

AC

22

23

21

26 25

27

28

31 30 29

24

RELAY BOX SIDE

A-08X

21

22

23

24

25

27 26

28

29

30

31

ACX01611AC

CONNECTOR A-08X
(RELAY BOX SIDE)