Mitsubishi Montero (2004+). Manual - part 597

REAR AIR CONDITIONING DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-31

STEP 2. Measure the resistance at rear heater control unit 
connector E-01.

(1) Disconnect rear heater control unit connector E-01, and 

measure at the wiring harness side.

(2) Turn the rear fan switch to the "ON" position.
(3) Turn the rear fan control switch to the "OFF" position.

(4) Measure the resistance between terminal 13 and ground.

• The measured value should be 2 ohms or less.

Q: Does the measured resistance value correspond with 

this range?
YES :  Go to Step 5.
NO :   Go to Step 3.

STEP 3. Check rear heater control unit connector E-01 and 
rear fan control switch connector E-12 for damage.

Q: Is rear heater control unit connector E-01 and rear fan 

control switch connector E-12 in good condition?
YES : Go to Step 4.
NO :  Repair or replace the connector. Refer to GROUP 

00E, Harness Connector Inspection 

P.00E-2

. Check 

that the air conditioning works normally.

AC204176

CONNECTOR : E-01

AU

HARNESS SIDE

7

8

3

10 9

2

4

11

1312

5

14

6

1

AC204738

7

8

3

10 9

2

4

11

1312

5

14

6

1

CG

HARNESS SIDE : E-01

AC204194

CONNECTORS : E-01, E-12

AL

E-01

E-01

E-12

HARNESS SIDE

E-12

HARNESS SIDE

7

8

3

10 9

2

4

11

1312

5

14

6

1

1
4

2

3

5

6

REAR AIR CONDITIONING DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-32

STEP 4. Check the wiring harness between rear heater 
control unit connector E-01 (terminal 13) and rear fan 
control switch connector E-12 (terminal 1).

NOTE: Also check intermediate connector E-06. If intermediate 
connector E-06 is damaged, repair or replace the connector as 
described in GROUP 00E, Harness Connector Inspection 

P.00E-2

.

Q: Is the wiring harness between rear heater control unit 

connector E-01 (terminal 13) and rear fan control switch 
connector E-12 (terminal 1) in good condition?
YES : Check that the rear air conditioning works normally.
NO :  Repair the wiring harness. Check that the rear air 

conditioning works normally.

AC204194

CONNECTORS : E-01, E-06, E-12

AZ

E-01

E-01

E-12

HARNESS SIDE

HARNESS SIDE

E-12

E-06

E-06

7

8

3

10 9

2

4

11

1312

5

14

6

1

1
4

2

3

5

6

22

2021

10

9

8

1718

6 7

19

1415

4 5

1112

1 2 3

13

16

REAR AIR CONDITIONING DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-33

STEP 5. Check rear heater control unit connector E-01 and 
rear heater switch E-21 for damage.

Q: Is rear heater control unit connector E-01 and rear 

heater switch E-21 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 rear air conditioning works normally.

STEP 6. Check the wiring harness between rear heater 
control unit connector E-01 (terminal 3, 4 and 8) and rear 

heater switch connector E-21 (terminal 5, 3 and 13).

AC204176

CONNECTOR : E-01

AU

HARNESS SIDE

7

8

3

10 9

2

4

11

1312

5

14

6

1

AC204175

CONNECTOR : E-21

AF

HARNESS SIDE

FLOOR 
COSOLE

1
7

2
8

10

11

5

13

6

14

12

4

9

3

AC204176

CONNECTOR : E-01

AU

HARNESS SIDE

7

8

3

10 9

2

4

11

1312

5

14

6

1

AC204175

CONNECTOR : E-21

AF

HARNESS SIDE

FLOOR 
COSOLE

1
7

2
8

10

11

5

13

6

14

12

4

9

3

REAR AIR CONDITIONING DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-34

NOTE: Also check intermediate connector D-112. If intermedi-
ate connector D-112 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 rear heater control unit 

connector E-01 (terminal 3, 4 and 8) and rear heater 
switch connector E-21 (terminal 5, 3 and 13) in good 
condition?
YES : Go to Step 7.
NO :  Repair the wiring harness. Check that the rear air 

conditioning works normally.

STEP 7. Check the air mixing damper control motor and 
potentiometer

CAUTION

Do not apply battery voltage when the damper is in the 
MAX HOT/MAX COOL position.
Check the air mixing damper control motor by the following pro-
cedures.

When checking the air mixing damper control motor, measure 
the resistance value between the terminals 3 and 5, between 
the terminals 3 and 7. At this time, make sure that the mea-
sured resistance value changes slowly within the standard 
value.

Standard value: 1.2 

− 4.8 kΩ

Q: Does air mixing damper control motor work normally?

YES : Go to Step 8.
NO :  Replace the air mixing damper control motor. Check 

that the rear air conditioning works normally. 

AC204171 AL

CONNECTOR : D-112

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

LEVER 
POSITION

BATTERY 
CONNECTION

LEVER 
OPERATION

At the MAX 
COOL position

• Connect terminal 1 

to the positive 
battery terminal

• Connect terminal 2 

to the negative 
battery terminal

The lever moves 
from the MAX 
COOL position to 
the MAX HOT 
position

At the MAX 
HOT position

• Connect terminal 2 

to the positive 
battery terminal

• Connect terminal 1 

to the negative 
battery terminal

The lever moves 
from the MAX HOT 
position to the MAX 
COOL position

AC001049AB

MAX HOT POSITION

MAX 
COOL 
POSITION