Mitsubishi Montero (2004+). Manual - part 817

INPUT SIGNAL PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-525

STEP 7. Check passenger's door switch connector F-22 for 
loose, corroded or damaged terminals, or terminals 
pushed back in the connector. 
Q: Is passenger's door switch connector F-22 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

. If the functions, which are described in 

"CIRCUIT OPERATION", work normally, the input 
signal from the passenger's door switch should be 
normal.

STEP 8. Check the passenger's door switch.
Remove the passenger's door switch. Then check the continu-
ity between the switch terminals and the switch body.

Q: Is the passenger's door switch in good condition?

YES : Go to Step 9.
NO :  Replace the passenger's door switch. If the functions, 

which are described in "CIRCUIT OPERATION", work 
normally, the input signal from the passenger's door 
switch should be normal.

STEP 9. Measure at the lower metal part of the passenger's 
door switch in order to check the ground circuit to the 
passenger's door switch.
NOTE: Check that the passenger's door switch is grounded to 
the vehicle body by means of its mounting screw.
Remove the cap, and measure the resistance value between 
the lower metal part and the ground. 

• The resistance should equal 2 ohms or less.

Q: Is the measured resistance 2 ohms or less?

YES : Go to Step 10.
NO :  Check the fit of the switch, and repair if necessary. If 

the functions, which are described in "CIRCUIT 
OPERATION", work normally, the input signal from 
the passenger's door switch should be normal.

AC204177

CONNECTOR : F-22

AE

HARNESS SIDE

1

2

3

F-22

SWITCH 
POSITION

TESTER 
CONNECTION

SPECIFIED 
CONDITION

Released (ON)

1 

− switch body

Less than 2 ohms

Depressed (OFF) 1 

− switch body

Open circuit

1 2 3

ACX01865 AC

ON

OFF

ACX01600AB

METAL PART

CUP

INPUT SIGNAL PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-526

STEP 10. Check ETACS-ECU connector D-224 for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector. 
Q: Is ETACS-ECU connector D-224 in good condition?

YES : Go to Step 11.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. If the functions, which are described in 

"CIRCUIT OPERATION", work normally, the input 
signal from the passenger's door switch should be 
normal.

STEP 11. Check the wiring harness between passenger's 
door switch connector F-22 (terminal 1) and ETACS-ECU 
connector D-224 (terminal 29).

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

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

AC204177

CONNECTOR : F-22

AE

HARNESS SIDE

1

2

3

F-22

INPUT SIGNAL PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-527

NOTE: Also check joint connector D-01 and intermediate con-
nector D-111 for loose, corroded, or damaged terminals, or ter-
minals pushed back in the connector. If joint connector D-01 or 
intermediate connector D-111 is damaged, Repair or replace 
the damaged component(s) as described in GROUP 00E, Har-
ness Connector Inspection 

P.00E-2

.

Q: Is the wiring harness between passenger's door switch 

connector F-22 (terminal 1) and ETACS-ECU connector 
D-224 (terminal 2) in good condition?
YES : Replace the ETACS-ECU. If the functions, which are 

described in "CIRCUIT OPERATION", work normally, 
the input signal from the passenger's door switch 
should be normal.

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. If the 
functions, which are described in "CIRCUIT 
OPERATION", work normally, the input signal from 
the passenger's door switch should be normal.

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 MB991958 and SWS monitor kit 
MB991862. For details on how to use the SWS mon-
itor, refer to "How to use SWS monitor 

P.54B-10

."

.

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

.

AC204170

CONNECTOR: D-01

AB

9 10

8

6 7

31 32

30

29

18 19 20 21

5

4

2

1

3

27

26

24

23

25

12 13 14 15 16 17

28

11
22
33

AC204171

CONNECTOR : D-111

BH

9

8

6 7

5

3 4

20

32

21

33

43

17 18

30

41

16

29

28

39 40

13

25

12

24

35 36

14

26

37

15

27

38

19

31

42

1

10

22

2

11

23

34

(HEAD)

COLUMN-ECU

COLUMN SWITCH

(TAIL)

(DIMMER) (PASSING)

(LH)

(RH)

TURN-SIGNAL
LIGHT SWITCH

DIMMER·PASSING
SWITCH

LIGHTING
SWITCH

Turn-Signal Light and Lighting Switch Input Circuit

INPUT SIGNAL PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-528

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

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 column-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) Turn the ignition switch to the "LOCK" (OFF) position.
(3) 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."

(4) Scan tool MB991958 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.54B-35

."

AC309091

MB991911

MB991827

MB991824 

AB

MB991806

MB991862

DATA LINK
CONNECTOR 
(16-PIN)

DATA LINK
CONNECTOR 
(13-PIN)