Mitsubishi Lancer Evolution IX. Manual - part 461

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-319

STEP 15. Check connector: D-12 fuel pump 
connector.

Q: Is the check result normal?

YES : 

Go to Step 16 .

NO : 

Repair or replace the connector.

STEP 16. Perform voltage measurement at D-12 
fuel pump connector.

• Disconnect connector, and measure at harness 

side.

• Ignition switch: "ON"

• Voltage between terminal No. 5 and earth.

OK: System voltage

Q: Is the check result normal? 

YES : 

Go to Step 17 .

NO : 

Check intermediate connectors C-113*

1

, 

C-112*

2

 C-123 and D-33, and repair if 

necessary. If intermediate connector are 
normal, check and repair harness between 
B-121 (terminal No. 2) fuel pump resistor 
connector and D-12 (terminal No. 5) fuel 
pump connector.

• Check power supply line for 

open/short circuit.

AK203611

1

2

3

4

5

AD

Connector:  D-12

D-12 (GR)

Harness side 
connector

AK203611

1

2

3

4

5

AD

Connector:  D-12

D-12 (GR)

Harness side 
connector

AK305259

1

2

Harness side connector

Connector: B-121

B-121(B)

B-121(B)

AB

<L. H. drive vehicles>

<R. H. drive vehicles>

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-320

STEP 17. Perform resistance measurement at 
D-12 fuel pump connector.

• Disconnect connector, and measure at harness 

side.

• Resistance between terminal No. 4 and earth.

OK: 2

Ω or less

Q: Is the check result normal?

YES : 

Replace fuel pump.

NO : 

Check intermediate connector D-34, and 

repair if necessary. If intermediate 
connector is normal, check and repair 
harness between D-12 (terminal No. 4) fuel 
pump connector and body earth.

• Check earthing line for open circuit 

and damage.

STEP 18. Check connector: B-120 fuel pump 
relay (3) connector.

Q: Is the check result normal?

YES : 

Go to Step 19 .

NO : 

Repair or replace the connector.

STEP 19. Check fuel pump relay (3).

• Fuel pump relay (3) continuity check (Refer to 

P.13A-402

).

Q: Is the check result normal?

YES : 

Go to Step 20 .

NO : 

Replace the fuel pump relay (3).

AK203611

1

2

3

4

5

AD

Connector:  D-12

D-12 (GR)

Harness side 
connector

AK305262

2 1

3

4

Harness side connector

Connector: B-120

B-120

B-120

AB

<L. H. drive vehicles>

<R. H. drive vehicles>

Junction block’s
triangle marks

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-321

STEP 20. Perform voltage measurement at B-120 
fuel pump relay (3) connector.

• Remove relay, and measure at junction block 

side.

• Ignition switch: "ON"

• Voltage between terminal No. 2 and earth, and 

No. 4 and earth.

OK: System voltage

Q: Is the check result normal? 

YES : 

Go to Step 21 .

NO : 

Check intermediate connector C-123, and 

repair if necessary. If intermediate 
connector is normal, check and repair 
harness between B-120 (terminal No. 2 and 
No. 4) fuel pump relay (3) connector and 
B-121 (terminal No. 1) fuel pump resistor 
connector.

• Check power supply line for damage.

STEP 21. Connector check: C-119 engine-ECU 
connector.

Q: Is the check result normal?

YES : 

Go to Stop 22 .

NO : 

Repair or replace the connector.

AK305262

2 1

3

4

Harness side connector

Connector: B-120

B-120

B-120

AB

<L. H. drive vehicles>

<R. H. drive vehicles>

Junction block’s
triangle marks

AK305259

1

2

Harness side connector

Connector: B-121

B-121(B)

B-121(B)

AB

<L. H. drive vehicles>

<R. H. drive vehicles>

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-322

STEP 22. Perform voltage measurement at C-119 
engine-ECU connector.

• Disconnect connector, and measure at harness 

side.

• Ignition switch: "ON"

• Disconnect C-121 (terminal No. 21) engine-ECU 

connector and earth.

• Voltage between terminal No. 55 and earth.

OK: System voltage

Q: Is the check result normal? 

YES : 

Go to Step 23 .

NO : 

Check and repair harness between C-119 

(terminal No.55) engine-ECU connector and 
B-120 (terminal No.3) fuel pump relay (3) 
connector.

• Check earthing line for open circuit 

and damage.

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>

AK305262

2 1

3

4

Harness side connector

Connector: B-120

B-120

B-120

AB

<L. H. drive vehicles>

<R. H. drive vehicles>

Junction block’s
triangle marks