Mitsubishi Lancer Evolution IX. Manual - part 449

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-271

STEP 15. Check harness between C-121 (terminal 
No. 8) engine-ECU connector and B-25 (terminal 
No. 1) alternator connector.

NOTE: Before checking harness, check intermediate 
connector B-14 and repair if necessary.

• Check output line for open/short circuit and dam-

age.

Q: Is the check result normal?

YES : 

Go to Step 16 .

NO : 

Repair the damaged harness wire.

STEP 16. Perform voltage measurement at C-121 
engine-ECU connector.

• Measure engine-ECU terminal voltage.

• Engine: Idling after warm-up

• Transmission: Neutral

• Radiator fan: Not operating

• Voltage between terminal No. 8 and earth.

OK: Switching the head lamps to ON from 
OFF causes the voltage to fall.

Q: Is the check result normal?

YES : 

Go to Step 20 .

NO : 

Go to Step 17 .

AK501995

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AB

Connector: C-121

C-121 (GR)

C-121 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

AK305036

M

2

1

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Harness side 
connector

AB

Connector : B-25

B-25(GR)

AK501995

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AB

Connector: C-121

C-121 (GR)

C-121 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-272

STEP 17. Connector check: C-119 engine-ECU 
connector and B-25 alternator connector.

Q: Is the check result normal?

YES : 

Go to Step 18 .

NO : 

Repair or replace the connector.

STEP 18. Check harness between C-119 (terminal 
No. 52) engine-ECU connector and B-25 (terminal 
No. 4) alternator connector.

NOTE: Before checking harness, check intermediate 
connector B-14, and repair if necessary.

• Check output line for open/short circuit and dam-

age.

Q: Is the check result normal?

YES : 

Go to Step 19 .

NO : 

Repair the damaged harness wire.

AK501994

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AB

Connector: C-119

C-119 (GR)

C-119 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

AK305036

M

2

1

3

4

Harness side 
connector

AB

Connector : B-25

B-25(GR)

AK501994

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AB

Connector: C-119

C-119 (GR)

C-119 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

AK305036

M

2

1

3

4

Harness side 
connector

AB

Connector : B-25

B-25(GR)

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-273

STEP 19. Check the trouble symptoms.

Q: Does trouble symptom persist?

YES : 

Replace the alternator.

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use 

Troubleshooting/Inspection Service Points 

P.00-5

).

STEP 20. Perform voltage measure at C-119 
engine-ECU connector.

• Measure engine-ECU terminal voltage.

• Engine: Idling

• A/C switch: ON (A/C compressor ON)

• Voltage between terminal No. 65 and earth.

OK: 

1 V or less (with outside air temperature sen-

sor ambient temperature at 18

°C or higher 

and A/C set for maximum air flow at mini-
mum temperature)

System voltage (with A/C set for minimum air 

flow at room temperature)

Q: Is the check result normal?

YES : 

Go to Step 21 .

NO : 

Check A/C load signal system (Refer to 
Inspection Procedure 29 

P.13A-352

).

STEP 21. Connector check: B-103 and B-114 
ignition coil connectors.

Q: Is the check result normal?

YES : 

Go to Step 22 .

NO : 

Repair or replace the connector.

STEP 22. Check ignition coil spark.

Q: Is the check result normal?

YES : 

Go to Step 27 .

NO : 

Go to Step 23 .

STEP 23. Check spark plug.

Q: Is the check result normal?

YES : 

Go to Step 24 .

NO : 

Replace the spark plug.

STEP 24. Check spark plug cable.

• Check spark plug cable itself (Refer to GROUP 

16 

− Ignition System − On-vehicle Service 

P.16-29

).

Q: Is the check result normal?

YES : 

Go to Step 25 .

NO : 

Replace the spark plug cable.

STEP 25. Check ignition coil itself.

• Check ignition coil itself (Refer to GROUP 16 − 

Ignition System 

− On-vehicle Service 

P.16-28

).

Q: Is the check result normal?

YES : 

Go to Step 26 .

NO : 

Replace the ignition coil.

AK501994

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AB

Connector: C-119

C-119 (GR)

C-119 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>

AK305047

1

2

3

Connector : B-103, B-114

B-114(GR)

B-103(GR)

AB

Harness side 
connector

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-274

STEP 26. Check harness between ignition coil 
connector terminal No. 2 of each cylinder and 
body earth.

• Check earthing line for open/short circuit and 

damage.

Q: Is the check result normal?

YES : 

Check and repair harness between ignition 

coil connector terminal No. 3 of each 
cylinder and C-121 engine-ECU.

• Check signal line for open/short and 

damage.

NO : 

Repair the damaged harness wire.

STEP 27. Check injector for spray condition.

• Check each injector for spray condition (Refer to 

P.13A-406

).

Q: Is the check result normal?

YES : 

Go to Step 28 .

NO : 

Replace the injector.

STEP 28. Check compression pressure.

• Check compression pressure (Refer to GROUP 

11A 

− On-vehicle Service 

P.11A-11

).

Q: Is the check result normal?

YES : 

Go to Step 29 .

NO : 

Repair.

STEP 29. Check purge control solenoid valve 
itself.

• Check purge control solenoid valve itself (Refer 

to GROUP 17 

− Emission Control System − 

Evaporative Emission Control System 

P.17-11

).

Q: Is the check result normal?

YES : 

Go to Step 30 .

NO : 

Replace the purge control solenoid valve.

STEP 30. Check EGR control solenoid valve 
itself.

• Check EGR control solenoid valve itself (Refer to 

GROUP 17 

− Emission Control System − 

Exhaust Gas Recirculation (EGR) System 

P.17-15

).

Q: Is the check result normal?

YES : 

Go to Step 31 .

NO : 

Replace the EGR control solenoid valve.

STEP 31. Check EGR valve itself.

• Check EGR valve itself (Refer to GROUP 17 − 

Emission Control System 

− Exhaust Gas Recir-

culation (EGR) System 

P.17-15

).

Q: Is the check result normal?

YES : 

Go to Step 32 .

NO : 

Replace the EGR valve.

STEP 32. M.U.T.-II/III actuator test

• Item No. 07: Fuel pump

OK: Operating sounds of fuel pump can be 
heard.

Q: Is the check result normal?

YES : 

Go to Step 33 .

NO : 

Check fuel pump system (Refer to 
inspection Procedure 24 

P.13A-313

).

AK305047

1

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Connector : B-103, B-114

B-114(GR)

B-103(GR)

AB

Harness side 
connector

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AB

Connector: C-121

C-121 (GR)

C-121 (GR)

Harness side connector

<L. H. drive vehicles>

<R. H. drive vehicles>