Mitsubishi Montero (2004+). Manual - part 659

AUTO A/C DIAGNOSIS

TSB Revision

AUTOMATIC AIR CONDITIONING

55B-125

NOTE: Also check joint connector (6) D-01, junction block con-
nectors D-210 and D-208. If joint connector (6) D-01, junction 
block connectors D-210 or D-208 is damaged, repair or replace 
the connector as described in GROUP 00E, Harness Connec-
tor Inspection 

P.00E-2

.

Q: Is the wiring harness between A/C-ECU connector D-24 

(terminal 26) and the ignition switch (IG2) in good 
condition?
YES : Check that the air conditioning works normally.
NO :  Repair the wiring harness. Check that the air 

conditioning works normally.

STEP 4. Measure the voltage at A/C-ECU connector D-24. 

(1) Disconnect A/C-ECU connector D-24 and measure the 

voltage at the harness side.

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

(3) Measure the voltage between terminal 27 and ground.

• The measured value should be approximately 12 volts 

(battery positive voltage).

Q: Does the measured voltage correspond with this range?

YES :  Go to Step 7.
NO :   Go to Step 5.

AC204191

CONNECTORS: D-208, D-210

D-208

AC

HARNESS SIDE

HARNESS SIDE

D-210

D-208

D-210

1

2

3

5

6

4

1

2

7 6

3

9

4

11

12

10

13

5

8

AC204170

CONNECTOR : D-24

D-24(B)

D-24(B)

CQ

22

23

30

31

25

26

33

34

32

24

28

3635

27

29

21

HARNESS 
SIDE

AC204738 DI

HARNESS SIDE : D-24

22

23

30

31

25

26

33

34

32

24

28

3635

27

29

21

AUTO A/C DIAGNOSIS

TSB Revision

AUTOMATIC AIR CONDITIONING

55B-126

STEP 5. Check A/C-ECU connector D-24 for damage.
Q:  Is A/C-ECU connector D-24 in good condition?

YES : Go to Step 6.
NO :  Repair or replace the connector. Refer to GROUP 

00E, Harness Connector Inspection 

P.00E-2

. Check 

that the air conditioning works normally.

STEP 6. Check the wiring harness between A/C-ECU 
connector D-24 (terminal 27) and the ignition switch (ACC).

NOTE: Also check intermediate connector D-28, junction block 
connectors D-221 and D-208. If intermediate connector D-28, 
junction block connector D-221 or D-208 is damaged, repair or 
replace the connector as described in GROUP 00E, Harness 
Connector Inspection 

P.00E-2

.

Q: Is the wiring harness between A/C-ECU connector D-24 

(terminal 27) and the ignition switch (ACC) in good 
condition?
YES : Check that the air conditioning works normally.
NO :  Repair the wiring harness. Check that the air 

conditioning works normally.

AC204170

CONNECTOR : D-24

D-24(B)

D-24(B)

CQ

22

23

30

31

25

26

33

34

32

24

28

3635

27

29

21

HARNESS 
SIDE

AC204188

CONNECTORS : D-24, D-28

D-24(B)

D-24(B)

D-28

CB

HARNESS SIDE

D-28

22

23

30

31

25

26

33

34

32

24

28

3635

27

29

21

2 3

27

32

28

33

16

15

4 5

19

18

29

17

34

7 8

35

22

21

9 10

30

36

31

37

25

24

23

6

20

1

14

26

11

13

12

38

AC204173

CONNECTOR : D-221

AJ

HARNESS SIDE

3

1

4

6 5

7

8

2

AUTO A/C DIAGNOSIS

TSB Revision

AUTOMATIC AIR CONDITIONING

55B-127

STEP 7. Measure the voltage at A/C-ECU connector D-24. 

(1) Disconnect A/C-ECU connector D-24 and measure the 

voltage at the harness side.

(2) Measure the voltage between terminal 28 and ground.

• The measured value should be approximately 12 volts 

(battery positive voltage).

Q: Does the measured voltage correspond with this range?

YES :  Go to Step 10.
NO :   Go to Step 8.

STEP 8. Check A/C-ECU connector D-24 for damage.

Q:  Is A/C-ECU connector D-24 in good condition?

YES : Go to Step 9.
NO :  Repair or replace the connector. Refer to GROUP 

00E, Harness Connector Inspection 

P.00E-2

. Check 

that the air conditioning works normally.

AC204170

CONNECTOR : D-24

D-24(B)

D-24(B)

CQ

22

23

30

31

25

26

33

34

32

24

28

3635

27

29

21

HARNESS 
SIDE

AC204738 DJ

HARNESS SIDE : D-24

22

23

30

31

25

26

33

34

32

24

28

3635

27

29

21

AC204170

CONNECTOR : D-24

D-24(B)

D-24(B)

CQ

22

23

30

31

25

26

33

34

32

24

28

3635

27

29

21

HARNESS 
SIDE

AUTO A/C DIAGNOSIS

TSB Revision

AUTOMATIC AIR CONDITIONING

55B-128

STEP 9. Check the wiring harness between A/C-ECU 
connector D-24 (terminal 28) and the fusible link (1).

NOTE: Also check intermediate connector D-28, joint connec-
tor (7) D-02. If intermediate connector D-28, joint connector (7) 
D-02 is damaged, repair or replace the connector as described 
in GROUP 00E, Harness Connector Inspection 

P.00E-2

.

Q: Is the wiring harness between A/C-ECU connector D-24 

(terminal 28) and the fusible link (1) in good condition?
YES : Check that the air conditioning works normally.
NO :  Repair the wiring harness. Check that the air 

conditioning works normally.

AC204188

CONNECTORS : D-02, D-24, D-28

D-24(B)

D-24(B)

D-28

D-02

CC

HARNESS SIDE

D-28

D-02

22

23

30

31

25

26

33

34

32

24

28

3635

27

29

21

2 3

27

32

28

33

16

15

4 5

19

18

29

17

34

7 8

35

22

21

9 10

30

36

31

37

25

24

23

6

20

1

14

26

11

13

12

38

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