Mitsubishi Montero (2002-2004). Manual - part 914

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

23Ac-139

STEP 25. Using scan tool MB991502, check data list item 
61: Transmission Range Switch.

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.
(2) Turn the ignition switch to the "ON" position.
(3) Set scan tool MB991502 to the data reading mode for item 

61, Transmission Range Switch.

• Move the selector lever to "P," "R," "N," "D" and sport 

mode positions and confirm that the selected transmis-
sion ranges match the positions. (Sport mode is indi-
cated as "D" on scan tool MB991502.)

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the switch operating properly?

YES : It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use Troubleshooting/
Inspection Service Points 

− How to Cope with 

Intermittent Malfunction 

P.00-6

.

NO :  Replace the PCM.

ACX01539AD

MB991502

16-PIN

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

23Ac-140

DTC 29: Vehicle Speed Sensor System

AC205193 AB

Vehicle Speed Sensor System Circuit

AC204170

CONNECTOR : D-03

CE

D-03 (GR)

58

57

67

66

56

54 55

64

59

53

52

62

61

63

65

60

51

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

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

23Ac-141

.

CIRCUIT OPERATION

• 4.8 − 5.2 volts voltage is applied to the vehicle 

speed sensor from the PCM (terminal 79). The 
vehicle speed sensor generates a pulse signal 
when the output terminal is opened and ground.

• The PCM compares the vehicle speed sensor 

signal to input shaft and output shaft speed sen-
sor signals.

• If the vehicle speed sensor becomes inoperative, 

the transmission will not shift normally.

.

DTC SET CONDITIONS

• If the PCM detects no pulse signal from the vehi-

cle speed sensor for continuous period of 30 sec-
onds under following conditions, it is judged as a 
vehicle sensor system malfunction and DTC 29 is 
set.

• Driving forward

• Output shaft speed is 900 r/min or more

.

TROUBLESHOOTING HINTS (The most likely 
causes for this code to be set are:)

• Malfunction of the vehicle speed sensor circuit

• Damaged harness, connector

• Malfunction of the PCM

AC204681AC

CONNECTOR: D-134

D-134 (GR)

61 62

63 64

65 66 67 68 69 70 71 72 73

82

89

81

88

80

79

78

77

87

86

85

76

75

74

84

83

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>

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DIAGNOSTIC TROUBLE CODE PROCEDURES

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DIAGNOSIS

Required Special Tool:

• MB991502: Scan Tool (MUT-II)

STEP 1. Check the speedometer.
Q: Is the speedometer operating properly?

YES : Go to Step 2.
NO :  Check the vehicle speed sensor. Refer to GROUP 

54A, Combination Meters Assembly and Vehicle 
Speed Sensor .

STEP 2. Using scan tool MB991502, check data list item 29: 
Vehicle Speed Sensor.

CAUTION

To prevent damage to scan tool MB991502, always turn the 
ignition switch to "LOCK" (OFF) position before connect-
ing or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Start the engine.
(3) Set scan tool MB991502 to data reading mode for item 29, 

Vehicle Speed Sensor.

• Check that the speedometer and scan tool MB991502 

display speed match when driving at a vehicle speed of 
40 km/h (25 mph).

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use Troubleshooting/
Inspection Service Points 

− How to Cope with 

Intermittent Malfunction 

P.00-6

.

NO :  Go to Step 3.

ACX01539AD

MB991502

16-PIN