Mitsubishi Montero (2002-2004). Manual - part 901

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

23Ac-87

STEP 5. Check the harness for open circuit or short circuit 
to ground between stoplight switch connector D-123 
terminal 2 and the power supply fuse.
Q: Is the harness wire in good condition?

YES : Go to Step 6.
NO :  Repair or replace the harness wire.

STEP 6. Measure the stoplight switch output voltage to the 
PCM at connector D-123 by backprobing.
(1) Remove the stoplight switch from the mounting bracket.
(2) Do not disconnect connector D-123.

(3) Measure the voltage between stoplight switch connector D-

123 terminal 1 and ground by backprobing.

• When the switch button is out (closed circuit), voltage 

should equal battery positive voltage.

• When the switch button is depressed (open circuit), volt-

age should measure less than 1.0 volt.

Q: Is the measured voltage battery positive voltage with 

the switch button released (closed circuit), and less 
than 1.0 volt with the switch button depressed (open 
circuit)?
YES : Go to Step 8.
NO :  Go to Step 7.

STEP 7. Check the stoplight switch.
Refer to GROUP 35A, On-vehicle Service 

− Stoplight Switch 

Check 

P.35A-116

.

Q: Does the stoplight switch pass the checks?

YES : Go to Step 8.
NO :  Replace the stoplight switch. Refer to GROUP 35A, 

Brake Pedal 

P.35A-132

.

AC204170

CONNECTOR : D-123

CG

4

2

3

1

AC204170

CONNECTOR : D-123

CG

4

2

3

1

AC204918 BA

D-123 HARNESS CONNECTOR : 
HARNESS SIDE

4

2

3

1

ACX02208

BRAKE PEDAL

STOPLIGHT
SWITCH

AD

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

23Ac-88

STEP 8. Measure the stoplight switch output voltage at 
PCM connector D-133 by backprobing.
(1) Install the stoplight switch into the mounting bracket if it was 

removed.

(2) Do not disconnect connector D-133.

(3) Measure the voltage between terminal 39 and ground by 

backprobing.

• When the brake pedal is depressed, voltage should 

measure battery positive voltage.

• When the brake pedal is not depressed, voltage should 

measure less than 1.0 volt.

Q: Is the measured voltage battery positive voltage with 

the brake pedal depressed (closed circuit), and less 
than 1.0 volt with the brake pedal released (open 
circuit)?
YES : Go to Step 11.
NO :  Go to Step 9.

AC204681AD

CONNECTOR: D-133

D-133 (GR)

31 32

33 34

35 36 37 38 39 40 41 42 43
44 45 46 47 48 49

50 51

52 53

54 55 56

57 58

AC204918 BC

D-133 HARNESS CONNECTOR : 
HARNESS SIDE

50

58

43

36 37

35
44
52

45

53

32

31

42

38 39 40 41

46

55

48

54

51

47

49
56

33 34

57

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

23Ac-89

STEP 9. Check joint connector D-29, D-116, intermediate 
connector D-125, E-111 and PCM connector D-133 for 
loose, corroded or damaged terminals, or terminals 
pushed back in the connector.

AC204188

CONNECTORS : D-29, D-125

D-29

BA

D-125

D-125

D-29

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

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-116

AN

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

AC204176

CONNECTOR : E-111

BF

15

4

14

37

36

26 27

12

11

35

34

23 24

3

13

25

9

2

8

32

20 21

6

5

17

29

30

18

1

7

19

31

10

22

33

16

28

38

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

23Ac-90

Q: Are the connectors and terminals in good condition?

YES : Go to Step 10.
NO :  Repair or replace the damaged components. Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-

2

.

AC204681AD

CONNECTOR: D-133

D-133 (GR)

31 32

33 34

35 36 37 38 39 40 41 42 43
44 45 46 47 48 49

50 51

52 53

54 55 56

57 58