Mitsubishi Montero (2002-2004). Manual — part 470

COMBINATION METERS ASSEMBLY AND VEHICLE SPEED SENSOR

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CHASSIS ELECTRICAL

54A-51

CIRCUIT OPERATION

• The ignition switch (IG1) circuit is the power sup-

ply for the engine coolant temperature gauge.

• Resistance value, which the engine coolant tem-

perature gauge unit sends to the combination
meter, is dependent on temperature of the engine
coolant. This change in resistance causes the cir-
cuit current to fluctuate, thus moving the needle
on the gauge.

.

TECHNICAL DESCRIPTION (COMMENT)
If there is an open in the ignition switch (IG1) circuit,
the gauge needle will not move at all. If there is an
open in the ground circuit, the gauge needle will
move down to the extreme cold position.

.

TROUBLESHOOTING HINTS

• Malfunction of the engine coolant temperature

gauge unit

• Malfunction of the combination meter (printed-cir-

cuit board or engine coolant temperature gauge
assembly)

• The wiring harness or connectors may have

loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector

DIAGNOSIS

Required Special Tool:
MB991223: Harness Set

STEP 1. Check the engine coolant temperature gauge by
observing the other meters.
Check to see that the speedometer, tachometer and fuel gauge
operate normally.
Q: Do all other meters operate?

YES < other meters all operate > : Go to Step 2.
NO < one of the meters do not operate > : Refer to

INSPECTION PROCEDURE 5

P.54A-55

.

STEP 2. Check the engine coolant temperature gauge unit.
Check to see that the engine coolant temperature gauge unit
operates normally. Refer to

P.54A-64

.

Q: Is the engine coolant temperature gauge unit normal?

YES : Go to Step 3.
NO : Replace the engine coolant gauge unit. The engine

coolant gauge should work normally.

COMBINATION METERS ASSEMBLY AND VEHICLE SPEED SENSOR

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CHASSIS ELECTRICAL

54A-52

STEP 3. Measure at combination meter connector D-32 in
order to the ground circuit to the fuel level sensor.
(1) Disconnect combination meter connector D-32 and

measure at the wiring harness side.

(2) Measure the resistance value between terminal 11 and

ground.

• The resistance should equal 2 ohms or less.

Q: Is the measured resistance 2 ohms or less?

YES : Go to Step 6.
NO : Go to Step 4.

STEP 4. Check combination meter connector D-32 for
loose, corroded or damaged terminals, or terminals
pushed back in the connector.
Q: Is combination meter connector D-32 in good

condition?
YES : Go to Step 5.
NO : Repair or replace the damaged component(s). Refer

to GROUP 00E, Harness Connector Inspection

P.00E-2

. The fuel gauge should work normally.

STEP 5. Check the wiring harness between combination
meter connector D-32 (terminal 11) and ground.
Q: Is the wiring harness between combination meter

connector D-32 (terminal 11) and ground in good
condition?
YES : There is no action to be taken.
NO : Repair the wiring harness. The fuel gauge should

work normally.

AC204170

CONNECTOR : D-32

CU

HARNESS SIDE

D-32(GR)

D-32(GR)

3

4

16

17

1

2

14

15

5

7 6

19

13

8

9

21

22

20

18

23

10

11

24

25

12

AC204738 EF

HARNESS SIDE: D-32

3

4

16

17

1

2

14

15

5

7 6

19

13

8

9

21

22

20

18

23

10

11

24

25

12

AC204170

CONNECTOR : D-32

CU

HARNESS SIDE

D-32(GR)

D-32(GR)

3

4

16

17

1

2

14

15

5

7 6

19

13

8

9

21

22

20

18

23

10

11

24

25

12

AC204170

CONNECTOR : D-32

CU

HARNESS SIDE

D-32(GR)

D-32(GR)

3

4

16

17

1

2

14

15

5

7 6

19

13

8

9

21

22

20

18

23

10

11

24

25

12

COMBINATION METERS ASSEMBLY AND VEHICLE SPEED SENSOR

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CHASSIS ELECTRICAL

54A-53

STEP 6. Check engine coolant temperature gauge unit
connector B-38 and combination meter connector D-03 for
loose, corroded or damaged terminals, or terminals
pushed back in the connector.
Q: Are engine coolant temperature gauge unit connector

B-38 and combination meter connector D-03 in good
condition?
YES : Go to Step 7.
NO : Repair or replace the damaged component(s). Refer

to GROUP 00E, Harness Connector Inspection

P.00E-2

. The engine coolant gauge should work

normally.

AC204168

CONNECTOR : B-38

B-38(B)

B-38(B)

AD

1

HARNESS
SIDE

AC204170

CONNECTOR : D-03

AC

D-03(GR)

HARNESS
SIDE

51

52

61 60

53

54

56

57

55

63

66 65 64

59

62

58

67

D-03(GR)

COMBINATION METERS ASSEMBLY AND VEHICLE SPEED SENSOR

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CHASSIS ELECTRICAL

54A-54

STEP 7. Check the wiring harness between engine coolant
temperature gauge unit connector B-38 (terminal 1) and
combination meter connector D-03 (terminal 64).

NOTE: Also check intermediate connector E-111. If intermedi-
ate connector E-111 is damaged, repair or replace the connec-
tor as described in GROUP 00E, Harness Connector
Inspection

P.00E-2

.

Q: Is the wiring harness between engine coolant

temperature gauge unit connector B-38 (terminal 1) and
combination meter connector D-03 (terminal 64) in good
condition?
YES : Repair or replace the combination meter. The engine

coolant gauge should work normally.

NO : Repair the wiring harness. The engine coolant gauge

should work normally.

AC204168

CONNECTOR : B-38

B-38(B)

B-38(B)

AD

1

HARNESS
SIDE

AC204170

CONNECTOR : D-03

AC

D-03(GR)

HARNESS
SIDE

51

52

61 60

53

54

56

57

55

63

66 65 64

59

62

58

67

D-03(GR)

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