Mitsubishi Lancer Evolution IX. Manual - part 468

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-347

STEP 7. Perform voltage measurement at A-36 
A/C compressor assembly connector.

• Disconnect connector, and measure at harness 

side.

• Remove B-13X (terminal No. 1 and No. 4) A/C 

compressor relay and short-circuit of harness 
side connector.

• Ignition switch: "ON"

• Voltage between terminal No. 1 and earth.

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 8 .

NO : 

Check intermediate connector A-13

*1

 or 

C-31

*2

, and repair if necessary. If 

intermediate connector is normal, check and 
repair harness between A-36 (terminal No. 
1) A/C compressor assembly connector and 
B-13X (terminal No. 4) A/C compressor 
relay connector.

• Check output line for open/short 

circuit.

STEP 8. Perform voltage measurement at C-121 
engine-ECU connector.

• Disconnect connector, and measure at harness 

side.

• Ignition switch: "ON"

• Voltage between terminal No. 20 and earth.

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 12 .

NO : 

Go to Step 9 .

AK502005

1

AB

Connector: A-36

Harness side 
connector

A-36 (B)

AK305270

2

1

3

4

B-13X

Connector: B-13X

AB

Harness side
connector

Relay box’s
triangle marks

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>

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-348

STEP 9. Connector check: C-121 engine-ECU 
connector 

Q: Is the check result normal?

YES : 

Go to Step 10 .

NO : 

Repair or replace the connector.

STEP 10. Check harness between B-13X 
(terminal No. 3) A/C compressor relay connector 
and C-121 (terminal No. 20) engine-ECU 
connector.

• Check earthing line for open/short circuit.

Q: Is the check result normal?

YES : 

Go to Step 11 .

NO : 

Repair the damaged harness wire.

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>

AK305270

2

1

3

4

B-13X

Connector: B-13X

AB

Harness side
connector

Relay box’s
triangle marks

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>

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-349

STEP 11. M.U.T.-II/III data list

• Item No. 49: A/C relay

a. Engine: Idling
b. A/C set temperature:

Maximum Cool when temperature in cabin is 

25

°C or more

Maximum Hot when temperature in cabin is 

25

°C or less

OK: 

ON (when A/C is ON)
OFF (when A/C is OFF)

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 12. Connector check: C-121 engine-ECU 
connector

Q: Is the check result normal?

YES : 

Go to Step 13 .

NO : 

Repair or replace the connector.

STEP 13. Check harness between B-13X 
(terminal No. 3) A/C compressor relay connector 
and C-121 (terminal No. 20) engine-ECU 
connector.

• Check earthing line for damage.

Q: Is the check result normal?

YES : 

Go to Step 14 .

NO : 

Repair the damaged harness wire.

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>

AK305270

2

1

3

4

B-13X

Connector: B-13X

AB

Harness side
connector

Relay box’s
triangle marks

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>

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-350

STEP 14. Connector check: C-208 ignition switch 
connector

Q: Is the check result normal?

YES : 

Go to Step 15 .

NO : 

Repair or replace the connector.

STEP 15. Check harness between C-208 (terminal 
No. 4) ignition switch connector and B-13X 
(terminal No. 2) A/C compressor relay connector.

NOTE: Before checking harness, check intermediate 
connectors C-124

*1

or C-122

*2

, C-210 and C-211, 

and repair if necessary.

• Check power supply line for damage.

Q: Is the check result normal?

YES : 

Go to Step 16 .

NO : 

Repair the damaged harness wire.

AK305251

1

2

3

4

5

6

Harness side connector

Connector: C-208

C-208

<L. H. drive vehicles>

<R. H. drive vehicles>

C-208

AB

AK305251

1

2

3

4

5

6

Harness side connector

Connector: C-208

C-208

<L. H. drive vehicles>

<R. H. drive vehicles>

C-208

AB

AK305270

2

1

3

4

B-13X

Connector: B-13X

AB

Harness side
connector

Relay box’s
triangle marks