Mitsubishi Montero (2004+). Manual - part 809

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-493

STEP 16. Check horn relay connector A-10X and joint 
connector (3) A-17 for loose, corroded or damaged 
terminals, or terminals pushed back in the connector.
Q: Is horn relay connector A-10X and joint connector (3) 

A-17 in good condition?
YES : Go to Step 17.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. All the vehicle horn (including the theft-alarm 

horn) should sound when the theft-alarm system is 
triggered.

STEP 17. Check the wiring harnesses among horn relay 
connector A-10X (terminal 4) and joint connector (3) A-17 
(terminal 1).
Q: Are the wiring harnesses among horn relay connector 

A-10X (terminal 4) and joint connector (3) A-17 (terminal 
1) in good condition?
YES : Go to Step 18.
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. All the 
vehicle horn (including the theft-alarm horn) should 
sound when the theft-alarm system is triggered.

AC204183

CONNECTOR : A-10X

RELAY BOX SIDE

AD

2 1

5

4

3

AC204167

CONNECTOR : A-17

AF

A-17(GR)

A-17(GR)

14

13

4

1112

5

3

10

8 9

2

7

1

6

AC204183

CONNECTOR : A-10X

RELAY BOX SIDE

AD

2 1

5

4

3

AC204167

CONNECTOR : A-17

AF

A-17(GR)

A-17(GR)

14

13

4

1112

5

3

10

8 9

2

7

1

6

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-494

STEP 18. Check ETACS-ECU connector D-223 for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.
Q: Is ETACS-ECU connector D-223 in good condition?

YES : Go to Step 19.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. All the vehicle horn (including the theft-alarm 

horn) should sound when the theft-alarm system is 
triggered.

STEP 19. Check the wiring harness between horn relay 
connector A-10X (terminal 1) and ETACS-ECU connector 
D-223 (terminal 42).

AC204174

CONNECTOR : D-223

AC

D-223(B)

D-223(B)

HARNESS SIDE

42

43

50

51

45

46

53

54

52

44

48

5655

47

49

41

AC204183

CONNECTOR : A-10X

RELAY BOX SIDE

AD

2 1

5

4

3

AC204174

CONNECTOR : D-223

AC

D-223(B)

D-223(B)

HARNESS SIDE

42

43

50

51

45

46

53

54

52

44

48

5655

47

49

41

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-495

NOTE: Also check intermediate connector D-28 for loose, cor-
roded, or damaged terminals, or terminals pushed back in the 
connector. If intermediate connectors D-28 is damaged, repair 
or replace the damaged component(s) as described in GROUP 
00E, Harness Connector Inspection 

P.00E-2

.

Q: Is the wiring harness between horn relay connector 

A-10X (terminal 1) and ETACS-ECU connector D-223 
(terminal 42) in good condition?
YES : Replace the ETACS-ECU. All the vehicle horn 

(including the theft-alarm horn) should sound when 
the theft-alarm system is triggered.

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. All the 
vehicle horn (including the theft-alarm horn) should 
sound when the theft-alarm system is triggered.

STEP 20. Check the horn.
(1) When the theft-alarm system is triggered, remove the horn 

(high or low) which does not sound.

(2) Connect the battery as shown, and Verify that the horn 

sounds.

Q: Is the horn normal?

YES : Go to Step 21.
NO :  Replace the defective horn. All the vehicle horn 

(including the theft-alarm horn) should sound when 
the theft-alarm system is triggered.

STEP 21. Check which horn is defective.
Q: Which horn does not sound?

horn (high)  : Go to Step 22.
horn (low)  : Go to Step 24.

AC204170

CONNECTOR : D-28

AI

2 3

27

32

28

33

16

15

4 5

19

18

29

17

34

7 8

35

22

21

9 10

30

36

31

37

25

24

23

6

20

1

14

26

11

13

12

38

ACX02352

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-496

STEP 22. Check joint connector (3) A-17 and horn (high) 
connector A-27 for loose, corroded or damaged terminals, 
or terminals pushed back in the connector.
Q: Are joint connector (3) A-17 and horn (high) connector 

A-27 in good condition?
YES : Go to Step 23.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. All the vehicle horn (including the theft-alarm 

horn) should sound when the theft-alarm system is 
triggered.

STEP 23. Check the wiring harness between joint 
connector (3) A-17 (terminal 2) and horn (high) connector 
A-27 (terminal 1).
Q: Is the wiring harness between joint connector (3) A-17 

(terminal 2) and horn (high) connector A-27 (terminal 1) 
in good condition?
YES : Go to Step 26.
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. All the 
vehicle horn (including the theft-alarm horn) should 
sound when the theft-alarm system is triggered.

AC204167

CONNECTOR : A-17

AF

A-17(GR)

A-17(GR)

14

13

4

1112

5

3

10

8 9

2

7

1

6

AC204166

CONNECTOR : A-27

HARNESS 
SIDE

A-27(B)

A-27(B)

AB

1

AC204167

CONNECTOR : A-17

AF

A-17(GR)

A-17(GR)

14

13

4

1112

5

3

10

8 9

2

7

1

6

AC204166

CONNECTOR : A-27

HARNESS 
SIDE

A-27(B)

A-27(B)

AB

1