Mitsubishi Montero Sport (2004+). Manual — part 233

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-345

STEP 2. Check the left bank heated oxygen sensor (rear).
(1) Disconnect the left bank heated oxygen sensor (rear)

connector E-48 and connect test harness special tool,
MB998464, 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.

(3) Perform a tracing for 5 minutes or more with the engine

speed of 4,500 r/min.

(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 heated

oxygen sensor (rear) output voltage.

Standard value: 0.6

− 1.0 volt

CAUTION

• Be very careful when connecting the jumper wire;

incorrect connection can damage the oxygen sensor.

• Be careful the heater is broken when voltage of beyond

12 volts is applied to the oxygen sensor heater.
NOTE: If the sufficiently high temperature (of approximate
400

°

C or more) is not reached although the oxygen sensor

is normal, the output voltage would be possibly low
although the rich air-fuel ratio. Therefore, if the output volt-
age is low, use a jumper wire to connect the terminal No.2
and the terminal No. 1 of the oxygen sensor with a (+) termi-
nal and (-) terminal of 12 volts power supply respectively,
then check again.

Q: Is the voltage between 0.6 and 1.0 volt?

YES : Go to Step 3.
NO : Replace the left bank heated oxygen sensor (rear).

Then go to Step 5.

AK200498

1

2

3

4

E-48(B)

AB

CONNECTOR: E-48

HARNESS
CONNECTOR:
COMPONENT SIDE

LEFT BANK
HEATED OXYGEN
SENSOR (REAR)

AKX01624

HEATED
OXYGEN
SENSOR
COMPONENT
SIDE
CONNECTOR

MD998464

WHITE

BLACK

AL

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-346

STEP 3. Check connector E-48 at left bank heated oxygen
sensor (rear) 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 5.

AK200498

1

2

3

4

E-48(B)

AB

CONNECTOR: E-48

HARNESS
CONNECTOR:
COMPONENT SIDE

LEFT BANK
HEATED OXYGEN
SENSOR (REAR)

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-347

STEP 4. Check for short circuit to ground between left
bank heated oxygen sensor (rear) connector E-48 (terminal
No. 4) and PCM connector C-91 (terminal No. 73).

NOTE: Check harness after checking intermediate connector
E-45 and C-79. If intermediate connector is damaged, repair or
replace it. Refer to Group 00E, Harness Connector Inspection

P.00E-2

.

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.

AK200498

1

2

3

4

E-48(B)

AB

CONNECTOR: E-48

HARNESS
CONNECTOR:
COMPONENT SIDE

LEFT BANK
HEATED OXYGEN
SENSOR (REAR)

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-348

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 P0157 set?

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