Mitsubishi Montero Sport (2004+). Manual - part 192

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-181

DTC SET CONDITIONS

Logic Flow Chart

.

START

V

F

 > =4.5V

2secs HAS PASSED

YES

YES

YES

NO

NO

NO

MALFUNCTION

MONITORING

CONDITIONS

YES

NO

MONITORING

CONDITIONS

+5V ON

AK301436

V

F

 < 0.2V

10secs HAS PASSED

YES

YES

NO

NO

END

MALFUNCTION

GOOD

MODULATE A/F CONDITION TO RICH

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-182

Check Conditions

• 3 minutes or more have passed since the starting 

sequence was completed.

• Right bank heated oxygen sensor (front) signal 

voltage has continued to be 0.2 volt or lower. 

• Engine coolant temperature is higher than 76°C 

(169

°F).

• Engine speed is higher than 1,200 r/min.

• Volumetric efficiency is higher than 25 percent.

• Monitoring time: 7 seconds.

Judgment Criteria

• Input voltage supplied to the PCM interface circuit 

is higher than 4.5 volts when 5 volts is applied to 
the right bank heated oxygen sensor (front) out-
put line via a resistor.

.

OBD-II DRIVE CYCLE PATTERN
 Refer to Diagnostic Function 

− OBD-II Drive Cycle − 

Procedure 6 

− Other Monitor 

P.13A-4

.

.

TROUBLESHOOTING HINTS (The most likely 
causes for this code to be set are:)

• Right bank heated oxygen sensor (front) deterio-

rated.

• Open circuit in right bank heated oxygen sensor 

(front) output line.

• Open circuit in right black heated oxygen sensor 

(front) ground line.

• Connector damage.

• PCM failed.

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: V.C.I

• MB991827: USB Cable

• MB991911: Main Harness B

• MD998464: Test Harness

STEP 1. Using scan tool MB991958, check data list item 39: 
Heated Oxygen Sensor Bank 1, Sensor 1 (right front).

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.
(2) Start the engine and run at idle.
(3) Set scan tool MB991958 to the data reading mode for item 

39, Heated Oxygen Sensor Bank 1, Sensor 1 (right front).

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

output voltage should measure 0.6 to 1.0 volt.

• Warm up the engine. When the engine is idling, the out-

put voltage should repeat 0.4 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.00-7

.

NO :  Go to Step 2.

AK303629AB

MB991911

MB991827

MB991824 

16-PIN

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-183

STEP 2. Measure the sensor output voltage at right bank 
heated oxygen sensor (front) connector A-07 by 
backprobing.
(1) Do not disconnect the connector A-07.
(2) Start the engine and run at idle.

(3) Measure the voltage between terminal No. 4 and ground by 

backprobing.

• Warm up the engine. When the engine is 2,500 r/min, 

the output voltage should repeat 0 to 0.8 volt alternately.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage within the specified range?

YES : Go to Step 3.
NO :  Go to Step 6.

AK200490

1

2

3

4

A-07(B)

AB

CONNECTOR: A-07

HARNESS 
CONNECTOR: 
COMPONENT SIDE

RIGHT BANK
HEATED OXYGEN
SENSOR (FRONT)

AKX01541AT

1 2
3 4

A-07 HARNESS 
CONNECTOR: 
HARNESS SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-184

STEP 3. Check connector A-07 at right bank heated 
oxygen sensor (front) and connector C-91 at PCM for 
damage.
Q: Is the connector in good condition?

YES : Go to Step 4.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 11.

AK200490

1

2

3

4

A-07(B)

AB

CONNECTOR: A-07

HARNESS 
CONNECTOR: 
COMPONENT SIDE

RIGHT BANK
HEATED OXYGEN
SENSOR (FRONT)

AK104028

98

78

71

88

89

76

77

72
79
91

73
80

74

75

81
92

82

83

93

84

85

94

86

87

95

96

90

97

AB

CONNECTOR: C-91

C-91(GR)

HARNESS CONNECTOR:
COMPONENT SIDE