Mitsubishi Montero (2002-2004). Manual - part 636

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-241

STEP 5. Using scan tool MB991502, check data list item 59: 
Heated Oxygen Sensor Bank 2, Sensor 2 (left rear).

CAUTION

To prevent damage to scan tool MB991502, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Start the engine and run at idle.
(3) Set scan tool MB991502 to the data reading mode for item 

59, Heated Oxygen Sensor Bank 2, Sensor 2 (left rear).

• Warming up the engine. When the engine is revved, the 

output voltage should repeat 0 volt and 0.6 to 1.0 volt 
alternately.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use Troubleshooting/
Inspection Service Points 

P.00-6

.

NO :  Replace the PCM. Then go to Step 15.

ACX01539

16-PIN

MB991502

AC

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

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STEP 6. Check harness connector C-15 at left bank heated 
oxygen sensor (rear) and harness connector D-135 at PCM 
for damage.
Q: Is the harness connector in good condition?

YES : Check harness connector E-112 at intermediate 

connector for damage, and repair or replace as 
required. Refer to GROUP 00E, Harness Connector 
Inspection. If intermediate connector E-112 is in good 
condition, repair harness wire between left bank 
heated oxygen sensor (rear) connector C-15 (terminal 
No. 4) and PCM connector D-135 (terminal No. 116) 
because of open circuit or harness damage. Then go 
to Step 15. 

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

Connector Inspection 

P.00E-2

. Then go to Step 15. 

AK201280

1

2

3

4

CONNECTOR: C-15

C-15(B)

AB

HARNESS 
CONNECTOR: 
COMPONENT SIDE

RIGHT BANK
HEATED OXYGEN
SENSOR (REAR)

AK200947

91

92

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99

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103

104

105

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111

112

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CONNECTOR: D-135

HARNESS CONNECTOR: 
COMPONENT SIDE

AB

PCM

D-135(GR)

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-243

STEP 7. Check harness connector C-15 at left bank heated 
oxygen sensor (rear) for damage.
Q: Is the harness connector in good condition?

YES : Go to Step 8.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 15. 

AK201280

1

2

3

4

CONNECTOR: C-15

C-15(B)

AB

HARNESS 
CONNECTOR: 
COMPONENT SIDE

RIGHT BANK
HEATED OXYGEN
SENSOR (REAR)

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-244

STEP 8. Check the continuity at left bank heated oxygen 
sensor (rear) harness side connector C-15.
(1) Disconnect the connector C-15 and measure at the harness 

side.

(2) Check for the continuity between terminal No. 2 and 

ground.

• Should be less than 2 ohms.

Q: Is the continuity normal?

YES : Go to Step 11.
NO :  Go to Step 9.

STEP 9. Check harness connector D-135 at PCM for 
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 10.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 15. 

AK201280

1

2

3

4

CONNECTOR: C-15

C-15(B)

AB

HARNESS 
CONNECTOR: 
COMPONENT SIDE

RIGHT BANK
HEATED OXYGEN
SENSOR (REAR)

AK000239 AX

1

2

4 3

C-15 HARNESS 
CONNECTOR: 
COMPONENT SIDE

AK200947

91

92

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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)