Mitsubishi Montero (2002-2004). Manual - part 626

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-201

STEP 12. Check for harness damage between left bank 
heated oxygen sensor (front) connector B-26 (terminal No. 
2) and PCM connector D-135 (terminal No. 96).
Q: Is the harness wire in good condition?

YES : Go to Step 13.
NO :  Repair it. Then go to Step 15.

AK201278

1

2

3

4

CONNECTOR: B-26

B-26(GR)

AB

HARNESS 
CONNECTOR: 
COMPONENT 
SIDE

RIGHT BANK
HEATED OXYGEN
SENSOR (FRONT)

AK200947

91

92

93

94

95

96

97

98

99

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

CONNECTOR: D-135

HARNESS CONNECTOR: 
COMPONENT SIDE

AB

PCM

D-135(GR)

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-202

STEP 13. Check for short circuit to ground and harness 
damage between left bank heated oxygen sensor (front) 
connector B-26 (terminal No. 4) and PCM connector D-135 
(terminal No. 108).
Q: Is the harness wire in good condition?

YES : Go to Step 14.
NO :  Repair it. Then go to Step 15.

AK201278

1

2

3

4

CONNECTOR: B-26

B-26(GR)

AB

HARNESS 
CONNECTOR: 
COMPONENT 
SIDE

RIGHT BANK
HEATED OXYGEN
SENSOR (FRONT)

AK200947

91

92

93

94

95

96

97

98

99

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

CONNECTOR: D-135

HARNESS CONNECTOR: 
COMPONENT SIDE

AB

PCM

D-135(GR)

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-203

STEP 14. Check the left bank heated oxygen sensor (front).
(1) Disconnect the left bank heated oxygen sensor (front) 

connector B-26 and connect test harness special tool, 
MB991316, to the connector on the left bank heated oxygen 
sensor (front) side.

(2) Warm up the engine until engine coolant 80

°C (176°F) or 

higher.

CAUTION

Be very careful when connecting the jumper wires; incor-
rect connection can damage the left bank heated oxygen 
sensor (front).

(3) Use the jumper wires to connect terminal No. 1 (red clip) to 

the positive battery terminal and terminal No. 3 (blue clip) to 
the negative battery terminal.

(4) Connect a digital volt meter between terminal No. 2 (black 

clip) and terminal No. 4 (white clip).

(5) While repeatedly revving the engine, measure the left bank 

heated oxygen sensor (front) output voltage.

Standard value: 0.6 

− 1.0 volt

Q: Is the voltage between 0.6 and 1.0 volt?

YES : Replace the PCM. Then go to Step 15.
NO :  Replace the left bank heated oxygen sensor (front). 

Then go to Step 15.

STEP 15. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to 

GROUP 13A, Procedure 6 

− Other Monitor 

P.13Ab-2

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0150 set?

YES : Retry the troubleshooting.
NO :  The inspection is complete.

AK201278

1

2

3

4

CONNECTOR: B-26

B-26(GR)

AB

HARNESS 
CONNECTOR: 
COMPONENT 
SIDE

RIGHT BANK
HEATED OXYGEN
SENSOR (FRONT)

AKX01625 AB

BLUE

JUMPER
WIRES

BLACK

RED

WHITE

MB991316

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-204

DTC P0151: Heated Oxygen Sensor Circuit Low Voltage (bank 2, sensor 1)

BL

ACK

BL

ACK

BL

ACK

TO PCM

FROM MFI RELAY

WHITE

AK201135

96

108

4

3

1

LEFT BANK
HEATED OXYGEN
SENSOR (FRONT)

POWERTRAIN CONTROL
MODULE (PCM)

11

9

7

2

4

3

1 2

B-26

MU802665

1

12

23 24 25 26

2

13

3

14

4

15

5

16

6

17

7

18

8

19

9

20 21 22

27 28 29 30 31 32 33

10 11

D-116

1
5

7 8

3 4
9 10

2
6

D-14

MU801335

Left Bank Heated Oxygen Sensor (front) Circuit

9192

939495

96979899

100

105

113114

115116117

118119120

106

107108109

110111112

101102103

104

D-135

(MU803805)

AK201277

CONNECTOR: B-26

B-26(GR)

AB

RIGHT BANK
HEATED OXYGEN
SENSOR (FRONT)

AK201038AF

CONNECTOR: D-135

PCM

D-135(GR)

AK201049

D-14

AB

CONNECTOR: D-14