Mitsubishi Lancer Evolution IX. Manual - part 393

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-47

STEP 6. Check harness between B-105 (terminal 
No. 5) air flow sensor connector and C-121 
(terminal No. 34) engine-ECU connector.

• Check earthing line for open circuit and damage.

Q: Is the check result normal? 

YES : 

Go to Step 7 .

NO : 

Repair the damaged harness wire.

STEP 7. M.U.T.-II/III data list

• Item No. 13: Intake air temperature sensor

OK: At ambient temperature or equivalent.

Q: Is the check result normal?

YES : 

Intermittent malfunction (Refer to GROUP 

00 

− How to Use 

Troubleshooting/Inspection Service Points 

P.00-5

).

NO : 

Replace the engine-ECU. 

STEP 8. Perform voltage measurement at B-105 
air flow sensor connector.

• Disconnect connector, and measure at harness 

side.

• Ignition switch: "ON" 

• Voltage between terminal No. 6 and earth.

OK: 4.5 

− 4.9 V

Q: Is the check result normal?

YES : 

Go to Step 13 .

NO : 

Go to Step 9 .

AK305005

3

4

5

1

2

6

7

AB

Connector : B-105

Harness side 
connector

B-105(B)

AK501995

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

31

32

33

34

35

1

10

AB

Connector: C-121

C-121 (GR)

C-121 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

AK305005

3

4

5

1

2

6

7

AB

Connector : B-105

Harness side 
connector

B-105(B)

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-48

STEP 9. Perform voltage measurement at C-119 
engine-ECU connector.

• Measure engine-ECU terminal voltage.

• Disconnect B-105 air flow sensor connector.

• Ignition switch: "ON"

• Voltage between terminal No. 62 and earth.

OK: 4.5 

− 4.9 V

Q: Is the check result normal?

YES : 

Go to Step 10 .

NO : 

Go to Step 11 .

STEP 10. Connector check: C-119 engine-ECU 
connector

Q: Is the check result normal?

YES : 

Check and repair harness between B-105 

(terminal No. 6) air flow sensor connector 
and C-119 (terminal No. 62) engine-ECU 
connector.

• Check output line for open circuit.

NO : 

Repair or replace the connector.

AK501994

65

43
50

42
49

41
48
60

61

64

46

47

58

59

67

68

45

56
66

52 51

44

53

62

54

63

57

55

AB

Connector: C-119

C-119 (GR)

C-119 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

AK305005

3

4

5

1

2

6

7

AB

Connector : B-105

Harness side 
connector

B-105(B)

AK501994

65

43
50

42
49

41
48
60

61

64

46

47

58

59

67

68

45

56
66

52 51

44

53

62

54

63

57

55

AB

Connector: C-119

C-119 (GR)

C-119 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

AK305005

3

4

5

1

2

6

7

AB

Connector : B-105

Harness side 
connector

B-105(B)

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-49

STEP 11. Connector check: C-119 engine-ECU 
connector

Q: Is the check result normal?

YES : 

Go to Step 12 .

NO : 

Repair or replace the connector.

STEP 12. Check harness between B-105 (terminal 
No. 6) air flow sensor connector and C-119 
(terminal No. 62) engine-ECU connector.

• Check output line for short circuit.

Q: Is the check result normal?

YES : 

Go to Step 7 .

NO : 

Repair the damaged harness wire.

AK501994

65

43
50

42
49

41
48
60

61

64

46

47

58

59

67

68

45

56
66

52 51

44

53

62

54

63

57

55

AB

Connector: C-119

C-119 (GR)

C-119 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

AK305005

3

4

5

1

2

6

7

AB

Connector : B-105

Harness side 
connector

B-105(B)

AK501994

65

43
50

42
49

41
48
60

61

64

46

47

58

59

67

68

45

56
66

52 51

44

53

62

54

63

57

55

AB

Connector: C-119

C-119 (GR)

C-119 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-50

STEP 13. Perform voltage measurement at B-105 
air flow sensor connector.

• Use special tool test harness (MB991709) to con-

nect only terminal No. 5 and No. 6, and then 
measure at pick-up harness.

• Ignition switch: "ON" 

• Voltage between terminal No. 6 and earth.

OK:

Ambient temperature at 

−20°C: 3.8 − 4.4 V

Ambient temperature at 0

°C: 3.2 − 3.8 V

Ambient temperature at 20

°C: 2.3 − 2.9 V 

Ambient temperature at 40

°C: 1.5 − 2.1 V 

Ambient temperature at 60

°C: 0.8 − 1.4 V

Ambient temperature at 80

°C: 0.4 − 1.0 V 

Q: Is the check result normal?

YES : 

Go to Step 7 .

NO : 

Go to Step 14 .

STEP 14. Connector check: C-119 engine-ECU 
connector

Q: Is the check result normal?

YES : 

Go to Step 15 .

NO : 

Repair or replace the connector.

AK305005

3

4

5

1

2

6

7

AB

Connector : B-105

Harness side 
connector

B-105(B)

AK501994

65

43
50

42
49

41
48
60

61

64

46

47

58

59

67

68

45

56
66

52 51

44

53

62

54

63

57

55

AB

Connector: C-119

C-119 (GR)

C-119 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>