Mitsubishi Montero (2004+). Manual - part 742

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-225

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

• ETACS-ECU

• Sunroof motor assembly (sunroof-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 CHK."

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 the "ETACS ECU" and "SUNROOF 
ECU" menus.

Q: Is "OK" displayed on the "ETACS ECU" and "SUNROOF 

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

Inspection Procedure A-3 "Communication with 
ETACS-ECU is not possible 

P.54B-42

."

"NG" is displayed on the "SUNROOF ECU" menu : 

Refer to Inspection Procedure A-5 "Communication 
with sunroof motor (sunroof-ECU) is not possible 

P.54B-56

."

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-226

STEP 2. Check the input signal by using "FUNCTION 
DIAG." menu of the SWS monitor.
(1) Turn the ignition switch to the "OFF" position to check the 

input signals from the following switches.

(2) Operate scan tool MB991958 according to the procedure 

below to display "SUNROOF-OPE."

1. Select "SYSTEM SELECT."
2. Select "SWS."
3. Select "SWS MONITOR."
4. Select "FUNCTION DIAG."
5. Select "SUNROOF."
6. Select "SUNROOF-OPE."

(3) Check that normal conditions are displayed on the items 

described in the table below.

Q: Are normal conditions displayed on the "IG SW (IG1)" 

and "S/R ECU ACK"?
Normal conditions displayed for all the items : Replace 

the sunroof motor assembly. The sunroof timer 
function should now work normally.

Normal condition is not displayed on the "IG SW(IG1)" : 

Refer to Inspection Procedure O-2 "ETACS-ECU 
does not receive a signal from the ignition switch 
(IG1) 

P.54B-505

."

Normal condition is not displayed on the "S/R ECU 
ACK" : Replace the sunroof motor assembly. The sunroof 

timer function should now work normally.

INSPECTION PROCEDURE F-4: Sunroof: Safety mechanism does not function.

.

TECHNICAL DESCRIPTION (COMMENT)
The sunroof motor assembly monitors load condition 
according to the current, which runs in the motor. If a 
predetermined current is exceeded, the sunroof 
motor reverses due to safety mechanism. If the sun-
roof motor does not reverse when an excessive load 
is applied, the sunroof motor assembly may be 
defective.

.

TROUBLESHOOTING HINT
The sunroof motor assembly may be defective

.

DIAGNOSIS
Replace the sunroof motor assembly.
Verify the sunroof safety mechanism should now work nor-
mally.

ITEM NO.

ITEM NAME

NORMAL 
CONDITION

ITEM 30

IG SW (IG1)

OFF

ITEM 72

S/R ECU ACK

NORMAL ACK

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-227

WINDSHIELD WIPER AND WASHER

GENERAL DESCRIPTION CONCERNING THE WINDSHIELD WIPER AND WASHER

M1549021500075

The following ECUs affect the functions and control 
of the windshield wiper and washer.

Windshield wiper and washer control function

.

Intermittent control
The ETACS-ECU calculates the intermittent time from the 
windshield wiper intermittent time adjusting knob at the column 
switch and sends it to the front-ECU as SWS data. 
The front-ECU determines the intermittent time T1 from the 
input SWS data signal, and turns ON the windshield wiper drive 
signal. When the wiper is at the STOP position, the windshield 
wiper auto-stop signal goes OFF to turn OFF the windshield 
wipe drive signal. After the intermittent time T1 seconds from 
when the windshield wiper drive signal turned ON, the wind-
shield wiper drive signal is turned ON again and the above 
operation is repeated.

.

Mist wiper control
When the ignition switch is at the ACC or ON posi-
tion, if the windshield mist wiper switch of the column 
switch is turned ON, the front-ECU turns ON the 
windshield wiper drive signal. At the same time, the 
wiper speed switching relay is turned ON 
(HIGH-SPEED). While the windshield mist wiper 
switch is ON, the windshield wiper will operate at 
high speed. Then, if the windshield mist wiper switch 
is turned off, the wiper operates at low speed until it 
stops at the predetermined park position.

When the windshield mist switch is turned on briefly, 
the wiper operates at low speed once.
At the point the windshield mist switch is turned ON, 
if the windshield wiper has been operating intermit-
tently, the same operations as the above will be per-
formed while the windshield mist wiper switch is ON. 
After the windshield mist wiper switch goes OFF, the 
intermittent operations will be set again T1 seconds 
after the windshield wiper auto-stop signal is turned 
ON last.

FUNCTION

CONTROL ECU

Intermittent control

ETACS-ECU, front-ECU, column switch

Mist wiper control

front-ECU, column switch

Low speed wiper, high speed wiper control

front-ECU, column switch

Washer control

front-ECU, column switch

AC200355AC

ON

OFF

ON

OFF

WINDSHIELD
WIPER 
AUTOSTOP 
SIGNAL

WINDSHIELD
WIPER DRIVE
SIGNAL

T1

T1

T1: Intermittent time

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-228

.

Low speed wiper, high speed wiper control
When the ignition switch is at the ACC or ON posi-
tion, if the windshield low speed wiper switch of the 
column switch is turned ON, the front-ECU turns ON 
the windshield wiper drive signal, turns OFF (LO) the 
windshield wiper speed switching relay, and operates 

the windshield wiper at low speed. Next, when the 
windshield high speed wiper switch is turned ON, the 
windshield wiper drive signal is turned ON, the wind-
shield wiper speed switching relay is turned ON (HI), 
and the windshield wiper is operated at high speed.

.

Washer control
When the ignition switch is at the ACC or ON posi-
tion, if the windshield washer switch of the column 
switch is turned ON, the front-ECU turns ON the 
windshield washer relay. The windshield wiper drive 
signal is turned ON in 0.3 second until 3 seconds 
after the windshield washer switch goes OFF to 

operate the windshield wiper continuously. When the 
windshield washer switch is turned ON, if the wind-
shield wiper is operating intermittently, intermittent 
operations will be continued after continuous opera-
tions.
NOTE: The wiper drive signal output time varies 
according to the conditions. Refer to the following 
table for details.

AC203080AB

ON

OFF

ON

OFF

ON

OFF

ON (HIGH)

WINDSHIELD MIST 
WIPER SWITCH

WINDSHIELD WIPER 
AUTO-STOP SIGNAL

WINDSHIELD WIPER 
DRIVE SIGNAL

WINDSHIELD WIPER 
SPEED SWITCHING 
RELAY

OFF (LOW)

WHEN WINDSHIELD 
WIPER SWITCH IS OFF

WHEN WINDSHIELD INTERMITTENT 
WIPER IS OPERATING

T1: Intermittent time

T1

T1

AC203089AB

ON

OFF

ON

OFF

ON

OFF

(HI) ON

WINDSHIELD LOW SPEED 
WIPER SWITCH

WINDSHIELD HIGH SPEED 
WIPER SWITCH

WINDSHIELD WIPER 
AUTO-STOP SIGNAL

ON

OFF

WINDSHIELD WIPER 
DRIVE SIGNA

WINDSHIELD WIPER SPEED 
SWITCHING RELAY

(LO) OFF

LOW SPEED OPERATIONS

HIGH SPEED OPERATIONS