Mitsubishi Montero (2002-2004). Manual — part 880

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

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DIAGNOSTIC TROUBLE CODE PROCEDURES

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.

CIRCUIT OPERATION

• The PCM (terminal 119) applies 5 volts to the

transmission fluid temperature sensor output ter-
minal (terminal 1).

• The transmission fluid temperature sensor circuit

is grounded to the PCM (terminal 96).

• When the transmission fluid temperature is cold,

the transmission fluid temperature sensor resis-
tance is high. When the transmission fluid tem-
perature is hot, the transmission fluid
temperature sensor resistance is low.

.

DTC SET CONDITIONS
If the transmission fluid temperature sensor output
voltage is greater than 4.5 volts after driving for 10
minutes or more (if the transmission fluid tempera-
ture does not increase), there is an open circuit in the
transmission fluid temperature sensor and DTC 15 is
set.

.

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

• Malfunction of the transmission fluid temperature

sensor circuit

• Damaged harness, connector

• Malfunction of the PCM

DIAGNOSIS

Required Special Tool:

• MB991502: Scan Tool (MUT-II)

AC204395

CONNECTOR : C-03

AE

C-03 (B)

6

10

4

9

5

3

8

2

7

1

AC204681AB

CONNECTOR: D-135

D-135 (GR)

91 92

93

101

94 95

96 97 98 99 100

102103

104

105106

107108 109

110 111112

113114

115116 117

118 119120

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>

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DIAGNOSTIC TROUBLE CODE PROCEDURES

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STEP 1. Using scan tool MB991502, check data list item 15:
Transmission Fluid Temperature Sensor.

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) Start the engine.
(3) Set scan tool MB991502 to data reading mode for item 15,

Transmission Fluid Temperature Sensor.

• When the engine is cool: Almost equal to the ambient

temperature (atmospheric temperature)
NOTE: Set scan tool MB991502 to data reading mode
for item number 13, Intake Air Temperature (IAT) Sensor
and note the temperature measurement. When the
engine is cool, the temperature should be almost equal
to the ambient temperature (atmospheric temperature),
and the IAT sensor measurement should be approxi-
mately the same as the transmission fluid temperature
sensor.

• When the engine is warm: 70 to 80°C (158 to 176°F)

(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 2.

ACX01539AD

MB991502

16-PIN

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

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DIAGNOSTIC TROUBLE CODE PROCEDURES

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STEP 2. Measure the sensor output voltage at the A/T
control solenoid valve assembly connector C-03 by
backprobing.
(1) Do not disconnect connector C-03.
(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal 1 and ground by

backprobing.

• When transmission fluid temperature is 20°C (68°F),

voltage should measure between 3.8 and 4.0 volts.

• When transmission fluid temperature is 40°C (104°F),

voltage should measure between 3.2 and 3.4 volts.

• When transmission fluid temperature is 80°C (176°F),

voltage should measure between 1.7 and 1.9 volts.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage within the specified range?

YES : Go to Step 6.
NO : Go to Step 3.

STEP 3. Measure the ground voltage at the A/T control
solenoid valve assembly connector C-03 by backprobing.
(1) Do not disconnect connector C-03.
(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal 2 and ground by

backprobing.

• The voltage should measure 0.5 volt or less.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage 0.5 volt or less?

YES : Go to Step 4.
NO : Go to Step 7.

AC204395

CONNECTOR : C-03

AE

C-03 (B)

6

10

4

9

5

3

8

2

7

1

AC204918 AI

C-03 HARNESS CONNECTOR :
HARNESS SIDE

6

9

5

10

8

3

7

2

1

4

AC204395

CONNECTOR : C-03

AE

C-03 (B)

6

10

4

9

5

3

8

2

7

1

AC204918 AL

C-03 HARNESS CONNECTOR :
HARNESS SIDE

6

9

5

10

8

3

7

2

1

4

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

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DIAGNOSTIC TROUBLE CODE PROCEDURES

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STEP 4. Check the sensor output voltage at A/T control
solenoid valve assembly connector C-03.
(1) Disconnect connector C-03 and measure at the harness

side.

(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal 1 and ground.

• The voltage should measure between 4.5 and 4.9 volts.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage between 4.5 and 4.9 volts?

YES : Go to Step 5.
NO : Go to Step 9.

AC204395

CONNECTOR : C-03

AE

C-03 (B)

6

10

4

9

5

3

8

2

7

1

AC204918 AJ

C-03 HARNESS CONNECTOR :
COMPONENT SIDE

1

8

2

7

9

4

10

5

6

3