Mitsubishi Montero Sport (2004+). Manual - part 196

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-197

STEP 4. Check for short circuit to ground and harness 
damage between right bank heated oxygen sensor (front) 
connector A-07 (terminal No. 4) and PCM connector C-91 
(terminal No. 72).
Q: Is the harness wire in good condition?

YES : Replace the PCM. Then go to Step 5.
NO :  Repair it. Then go to Step 5.

STEP 5. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to 

Diagnostic Function 

− OBD-II Drive Cycle − Procedure 6 − 

Other Monitor 

P.13A-4

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0131 set?

YES : Repeat the troubleshooting.
NO :  The procedure is complete.

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

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-198

DTC P0132: Heated Oxygen Sensor Circuit High Voltage (bank 1, sensor 1)

BLA

CK

BLA

CK

WHITE

BLA

CK-RED

AK000444

Right Bank Heated Oxygen Sensor (front) Circuit

4

POWERTRAIN CONTROL MODULE (PCM)

12

2

3

1

18

57

72

RIGHT BANK HEATED OXYGEN
SENSOR (FRONT)

TO PCM

FROM MFI RELAY

C-90

C-91

1 2
3 4

A-07
MU802605

47

41

42 43

48 49 50 51 52 53 54 55 56 57

46

45

44

58

59

60 61 62 63

64 65 66

C-90
(MU803781)

71

76

77

72 73 74

75

79 80

78

81

87 88

89

91

90

92

97

98

82

93

83

94

84 85

95

86

96

C-91
(MU803782)

1

10

2 3 4 5 6 7 8 9

11

12 13 14 15 16 17 18 19 20 21 22

23 24 25 26 27 28 29 30 31 32 33

C-71

JOINT
CONNECTOR (4)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-199

.

CIRCUIT OPERATION

• A voltage corresponding to the oxygen concen-

tration in the exhaust gas is sent to the PCM (ter-
minal No. 72) from the output terminal (terminal 
No. 4) of the right bank heated oxygen sensor 
(front).

• Terminal No. 2 of the right bank heated oxygen 

sensor (front) is grounded with PCM (terminal 
No. 57).

.

TECHNICAL DESCRIPTION

• The right bank heated oxygen sensor (front) 

detects the concentration of oxygen in the 
exhaust gas; it converts those data to voltage, 
and inputs the resulting signals to the PCM.

• When the right bank heated oxygen sensor 

(front) begins to deteriorate, the heated oxygen 
sensor signal response becomes poor.

• The PCM forcibly varies the air/fuel mixture to 

make it leaner and richer, and checks the 
response speed of the right bank heated oxygen 
sensor (front). In addition, the PCM also checks 
for an open circuit in the right bank heated oxy-
gen sensor (front) output line.

.

DESCRIPTIONS OF MONITOR METHODS
Right bank heated oxygen sensor (front) output volt-

age is over specified range.

.

MONITOR EXECUTION
Continuous

.

AK200489

A-07(B)

RIGHT BANK
HEATED OXYGEN
SENSOR (FRONT)

AB

CONNECTOR: A-07

AK103912AB

CONNECTOR: C-71

C-71

AK103738AE

CONNECTORS: C-90, C-91

PCM

C-91(GR)

C-90(GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-200

MONITOR EXECUTION CONDITIONS (Other 
monitor and Sensor)

Other Monitor (There is no temporary DTC stored 

in memory for the item monitored below)

• Heated oxygen sensor heater (front) monitor

• Misfire monitor

• Fuel system monitor

Sensor (The sensor below is determined to be 

normal)

• Volume airflow sensor

• Engine coolant temperature sensor

• Intake air temperature sensor

• Barometric pressure sensor

• Throttle position sensor

.

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• 2 seconds or more have passed since the start-

ing sequence was completed.

Judgment Criteria

• Right bank heated oxygen sensor (front) output 

voltage has continued to be 1.2 volts or higher for 
2 seconds.

.

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: )

• Short circuit in right bank heated oxygen sensor 

(front) output line.

• Connector damage.

• PCM failed.

START

END

NO

NO

YES

YES

MALFUNCTION

GOOD

2secs HAVE PASSED?

OUTPUT VOLTAGE > 1.2V

NO

YES

MONITORING

CONDITIONS

AK301437