Mitsubishi Lancer Evolution IX. Manual - part 401

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-79

Q: Is the check result normal?

YES : 

Check and repair harness between B-113 

(terminal No. 2) oxygen sensor (front) 
connector and C-119 (terminal No. 49) 
engine-ECU connector.

• Check earthing line for damage.

NO : 

Repair or replace the connector.

STEP 9. Perform voltage measurement at B-113 
oxygen sensor (front) connector.

• Use special tool test harness (MD998464) to con-

nect connector, and measure at pick-up harness.

• Engine: After warm-up

• Voltage between terminal No. 4 and earth.

OK:

600 

− 1,000 mV when 200 mV or lower abrupt 

racing is done a few seconds after abrupt 
deceleration from 4,000 r/min.

Q: Is the check result normal?

YES : 

Go to Step 12 .

NO : 

Go to Step 10 .

STEP 10. Check oxygen sensor (front) itself

• Check oxygen sensor itself (Refer to 

P.13A-404

).

Q: Is the check result normal?

YES : 

 Go to Step 11 .

NO : 

Replace the oxygen sensor (front).

STEP 11. Connector check: C-117 engine-ECU 
connector

AK305011

1

2

3

4

AB

Connector : B-113

Harness side 
connector

B-113(B)

Oxygen sensor(front)

AK501996

80

87

81

94

85

82

84

93

86

98

99

74

92

73

83

88

91

95

97 96

100

89

78

71

90

76

77

75

72
79

AB

Connector: C-117

C-117 (GR)

C-117 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

AK305011

1

2

3

4

AB

Connector : B-113

Harness side 
connector

B-113(B)

Oxygen sensor(front)

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-80

Q: Is the check result normal?

YES : 

Check and repair harness between B-113 

(terminal No. 4) oxygen sensor (front) 
connector and C-117 (terminal No. 71) 
engine-ECU connector.

• Check output line for damage.

NO : 

Repair or replace the connector.

STEP 12. Perform voltage measurement at C-117 
engine-ECU connector.

• Measure engine-ECU terminal voltage.

• Transmission: Neutral

• Engine: After warm-up

• Voltage between terminal No. 71 and earth.

OK:

600 

− 1,000 mV when 200 mV or lower abrupt 

racing is done a few seconds after abrupt 
deceleration from 4,000 r/min.

Q: Is the check result normal?

YES : 

Go to Step 14 .

NO : 

Go to Step 13 .

STEP 13. Connector check: C-117 engine-ECU 
connector

AK501996

80

87

81

94

85

82

84

93

86

98

99

74

92

73

83

88

91

95

97 96

100

89

78

71

90

76

77

75

72
79

AB

Connector: C-117

C-117 (GR)

C-117 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

AK501996

80

87

81

94

85

82

84

93

86

98

99

74

92

73

83

88

91

95

97 96

100

89

78

71

90

76

77

75

72
79

AB

Connector: C-117

C-117 (GR)

C-117 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

AK305011

1

2

3

4

AB

Connector : B-113

Harness side 
connector

B-113(B)

Oxygen sensor(front)

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-81

Q: Is the check result normal?

YES : 

Check and repair harness between B-113 

(terminal No. 4) oxygen sensor (front) 
connector and C-117 (terminal No. 71) 
engine-ECU connector.

• Check output line for open circuit.

NO : 

Repair or replace the connector.

STEP 14. Connector check: C-117 engine-ECU 
connector

Q: Is the check result normal?

YES : 

Go to Step 6 .

NO : 

Repair or replace the connector.

AK501996

80

87

81

94

85

82

84

93

86

98

99

74

92

73

83

88

91

95

97 96

100

89

78

71

90

76

77

75

72
79

AB

Connector: C-117

C-117 (GR)

C-117 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-82

Code No. P0135: Oxygen Sensor Heater (front) System

OPERATION

• Power is supplied to the heater power terminal 

(terminal No. 1) of the oxygen sensor (front) con-
nector from the engine control relay (terminal No. 
4).

• The heater (terminal No. 3) of the oxygen sensor 

(front) connector is controlled by the power tran-
sistor in the engine-ECU (terminal No. 3).

1

2

3

4

1

2

3

4

AK501806

2

3 4

5 6

7 8

9

11 12 13 14 15 16 17 18 19 20

30

21 22 23

24 25

26 27 28 29

3132 33

34 35

1

10

B-12X

B-Y

B-Y

B-Y

Oxygen sensor (front)

1

2

3

4

To engine-ECU

Engine-ECU

3

L-R

R-Y

Engine
control
relay

Oxygen sensor heater (front) circuit

Battery

Wire colour code
B: Black  LG: Light green  G: Green  L: Blue  W: White  Y: Yellow  SB: Sky blue  BR: Brown  O: Orange  GR: Gray
R: Red  P: Pink  V: Violet  PU: Purple

AB

C-121

(MU803783)

6 <A-13> (*1) or 
13 <C-31> (*2)

2 

1

4

3

B-113

MU802605

NOTE

*1: L.H. drive vehicles
*2: R.H. drive vehicles

To engine-ECU