Mitsubishi Montero (2002-2004). Manual - part 910

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

23Ac-123

DTC 28: Transmission Range Switch System (Short Circuit)

.

Transmission Range Switch System Circuit
Refer to 

P.23Ac-93

.

.

CIRCUIT OPERATION
Refer to 

P.23Ac-93

.

.

DTC SET CONDITIONS
If the PCM detects more than one transmission 
range switch input signal for thirty seconds, it is 
determined that there is a short circuit in the trans-
mission range switch and DTC 28 is set.

.

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

• Malfunction of the transmission range switch

• Malfunction of the ignition switch

• Damaged harness, connector

• Malfunction of the PCM

DIAGNOSIS

Required Special Tool:

• MB991502: Scan Tool (MUT-II)

STEP 1. Check the transmission range switch.
Measure the resistance between the terminals for each selec-
tor position as indicated in the table above.

Q: Does the resistance measure less than 2 ohms for each 

selector position?
YES : Go to Step 2.
NO :  Replace the transmission range switch. Refer to 

GROUP 23B, Transmission 

P.23B-18

.

STEP 2. Check transmission range switch connector C-04 
for loose, corroded or damaged terminals, or terminals 
pushed back in the connector.
Q: Are the connector and terminals in good condition?

YES : Go to Step 3.
NO :  Repair or replace the damaged components. Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-

2

.

TRANSMISSION 
RANGE

TERMINAL 
CONNECTION OF 
TESTER

SPECIFIED 
CONDITION

P

1 

− 7

Less than 2 ohms.

R

7 

− 8

N

2 

− 7

D

3 

− 7

ACX01187AD

P

R

N

D

AC204395

CONNECTOR : C-04

AF

C-04 (B)

4
9

5

10

3
8

2
7

6

1

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

23Ac-124

STEP 3. Check PCM connector D-134 for loose, corroded 
or damaged terminals, or terminals pushed back in the 
connector.
Q: Are the connector and terminals in good condition?

YES : Go to Step 4.
NO :  Repair or replace the damaged components. Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-

2

.

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

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

23Ac-125

STEP 4. Measure the switch output voltage at PCM 
connector D-134 by backprobing. ("P" position)
(1) Do not disconnect connector D-134.
(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal 66 and ground by 

backprobing.

• When transmission range is "P," voltage should mea-

sure battery positive voltage.

• When transmission range is "R," voltage should mea-

sure 0.5 volt or less.

• When transmission range is "N," voltage should mea-

sure 0.5 volt or less.

• When transmission range is "D," voltage should mea-

sure 0.5 volt or less.

Q: Is the measured voltage within the specified range?

YES : Go to Step 9.
NO :  Turn the ignition switch to the "LOCK" (OFF) position. 

Go to Step 5.

STEP 5. Check intermediate connector E-114 for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.
Q: Are the connector and terminals in good condition?

YES : Go to Step 6.
NO :  Repair or replace the damaged components. Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-

2

.

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

AC204918 BF

D-134 HARNESS CONNECTOR : 
HARNESS SIDE

76

85

65

72

71

73

82

75

81

74

63 64

66

70

69

68

67

78

87

79

88 89

80

77

86

62

61

83 84

AC204176

CONNECTOR : E-114

BD

38

28

16

33

22

10

31

19

7

1

18

30

29

17

5

6

21

20

32

8

2

9

25

13

3

24

23

3435

1112

27

26

3637

14

4

15

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

23Ac-126

STEP 6. Check harness for open circuit or short circuit to 
ground between transmission range switch connector C-
04 terminal 1 and PCM connector D-134 terminal 66.
Q: Is the harness wire in good condition?

YES : Go to Step 7.
NO :  Repair or replace the harness wire.

AC204395

CONNECTOR : C-04

AF

C-04 (B)

4
9

5

10

3
8

2
7

6

1

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