Mitsubishi Montero (2002-2004). Manual - part 371

INPUT SIGNAL PROCEDURES

TSB Revision

SWS INPUT SIGNAL PROCEDURES

54Bc-31

INSPECTION PROCEDURE O-6: Column Switch: ETACS-ECU does not receive any signal from the 
taillight switch, the headlight switch, the passing light switch, the dimmer switch or the turn-signal 
light switch.

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

."

.

CIRCUIT OPERATION
The ETACS-ECU operates the following equipment 
or functions according to signal from the column 
switch (turn-signal light and lighting switch):

• Light reminder tone alarm function

• Headlight

• Turn-signal light

.

TECHNICAL DESCRIPTION (COMMENT)
If the signal is not normal, the equipment or func-
tions, which are described in "CIRCUIT OPERA-
TION", do not work normally. If the signal is not 
normal, the column switch (turn-signal light and light-
ing switch) or the ETACS-ECU may be defective.

.

TROUBLESHOOTING HINTS

• The column switch (lighting and turn-signal light 

switch) may be defective

• The ETACS-ECU may be defective

• The wiring harness or connectors may have 

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

Turn-signal Light and Lighting Switch Input Circuit

INPUT SIGNAL PROCEDURES

TSB Revision

SWS INPUT SIGNAL PROCEDURES

54Bc-32

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 column-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 "COLUMN ECU" menu. 

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

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

with column switch (column-ECU) is not possible 

P.54Bb-16

."

STEP 2. Replace the ECU.
(1) Replace the column switch (lighting and turn-signal light 

switch).

(2) If the functions, which are described in "CIRCUIT 

OPERATION", work normally, the input signal from the 
column switch (lighting and turn-signal light switch) should 
be normal.

Q: Does the column switch (lighting and turn-signal light 

switch) send normal signal to the ECU?
YES : No action is necessary and testing is complete.
NO :  Replace the ETACS-ECU. If the functions, which are 

described in "CIRCUIT OPERATION", work normally, 
the input signal from the column switch (lighting and 
turn-signal light switch) should be normal.

AC204222AB

16-pin

13-pin

MB991502

MB991862

INPUT SIGNAL PROCEDURES

TSB Revision

SWS INPUT SIGNAL PROCEDURES

54Bc-33

INSPECTION PROCEDURE O-7: Column Switch: ETACS-ECU does not receive any signal from 
windshield mist wiper switch, windshield intermittent wiper switch, windshield low-speed wiper 
switch, windshield high-speed wiper switch, windshield washer switch, rear wiper switch or rear 
washer switch.

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

."

.

CIRCUIT OPERATION
The ETACS-ECU operates the following equipment 
according to signal from the column switch (wind-
shield wiper and washer switch):

• Windshield wiper and washer

• Rear wiper and washer

.

TECHNICAL DESCRIPTION (COMMENT)
If the signal is not normal, the equipment, which is 
described in "CIRCUIT OPERATION", does not work 
normally.

.

TROUBLESHOOTING HINTS

• The column switch (windshield wiper and washer 

switch) may be defective

• The ETACS-ECU may be defective

• The wiring harness or connectors may have 

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

Windshield Wiper and Washer Switch Input Circuit

INPUT SIGNAL PROCEDURES

TSB Revision

SWS INPUT SIGNAL PROCEDURES

54Bc-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 column-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 "COLUMN ECU" menu.

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

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

with column switch (column-ECU) is not possible 

P.54Bb-16

."

AC204222AB

16-pin

13-pin

MB991502

MB991862