Mitsubishi Montero (2002-2004). Manual - part 633

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-229

STEP 3. Measure the power supply voltage at left bank 
heated oxygen sensor (front) harness side connector B-26.
(1) Disconnect the connector B-26 and measure at the harness 

side.

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

(3) Measure the voltage between terminal No. 1 and ground.

• Voltage should be battery positive voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is battery positive voltage (approximately 12 volts) 

present?
YES : Go to Step 5.
NO :  Go to Step 4.

STEP 4. Check harness connector B-22X at the MFI relay 
for damage.
Q: Is the harness connector in good condition?

YES : Repair harness wire between MFI relay connector B-

22X (terminal No. 1) and left bank heated oxygen 
sensor (front) connector B-26 (terminal No. 1) 
because of open circuit or short circuit to ground. 
Then go to Step 12.

NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 12. 

AK201278

1

2

3

4

CONNECTOR: B-26

B-26(GR)

AB

HARNESS 
CONNECTOR: 
COMPONENT 
SIDE

RIGHT BANK
HEATED OXYGEN
SENSOR (FRONT)

AKX01496

B-26 HARNESS 
CONNECTOR: 
COMPONENT SIDE

1

2

3

4

AR

AK200951

2 1

3

4

B-22X

AB

CONNECTOR: B-22X

HARNESS 
CONNECTOR: 
COMPONENT SIDE

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-230

STEP 5. Meaure the power supply voltage at PCM 
connector D-132 by backprobing.
(1) Do not disconnect the connector D-132.
(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal No. 10 and ground 

by backprobing.

• Voltage should be battery positive voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is battery positive voltage (approximately 12 volts) 

present?
YES : Go to Step 8.
NO :  Go to Step 6.

STEP 6. Check harness connector D-132 at PCM for 
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 7.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 12. 

AK200938

2

3

4

5

6

7

8

9

1

10

14

15

16

17

18

19

20

21

22

23

24

25

26

27

11

12

13

AB

CONNECTOR: D-132

HARNESS CONNECTOR: 
COMPONENT SIDE

PCM

D-132(GR)

AK201411

1

2

3

5

6 7 8 9

4

20

21 22

232425

2627

10111213

14 15

16 1718

19

D-132 HARNESS 
CONNECTOR: 
HARNESS SIDE

AB

AK200938

2

3

4

5

6

7

8

9

1

10

14

15

16

17

18

19

20

21

22

23

24

25

26

27

11

12

13

AB

CONNECTOR: D-132

HARNESS CONNECTOR: 
COMPONENT SIDE

PCM

D-132(GR)

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-231

STEP 7. Check for open circuit or short circuit to ground 
between left bank heated oxygen sensor (front) connector 
B-26 (terminal No. 3) and PCM connector D-132 (terminal 
No. 27).
Q: Is the harness wire in good condition?

YES : Replace the PCM. Then go to Step 12. 
NO :  Repair it. Then go to Step 12.

AK201278

1

2

3

4

CONNECTOR: B-26

B-26(GR)

AB

HARNESS 
CONNECTOR: 
COMPONENT 
SIDE

RIGHT BANK
HEATED OXYGEN
SENSOR (FRONT)

AK200938

2

3

4

5

6

7

8

9

1

10

14

15

16

17

18

19

20

21

22

23

24

25

26

27

11

12

13

AB

CONNECTOR: D-132

HARNESS CONNECTOR: 
COMPONENT SIDE

PCM

D-132(GR)

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-232

STEP 8. Check harness connector D-132 at PCM for 
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 9.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 12. 

AK200938

2

3

4

5

6

7

8

9

1

10

14

15

16

17

18

19

20

21

22

23

24

25

26

27

11

12

13

AB

CONNECTOR: D-132

HARNESS CONNECTOR: 
COMPONENT SIDE

PCM

D-132(GR)