Mitsubishi Lancer Evolution IX. Manual — part 427

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-183

FUNCTION

• In response to a signal from the engine-ECU, the

purge control solenoid valve controls the flow rate
of the purge air to be introduced into the surge
tank.

TROUBLE JUDGMENT

Check Conditions

• Ignition switch: "ON"

• The battery voltage is 10 V or more.

Judgment Criterion

• The surge voltage (system voltage +2 V) of sole-

noid coil is not detected when the purge control
solenoid valve is turned to OFF from ON.

PROBABLE CAUSES

• Failed purge control solenoid valve

• Open/short circuit in purge control solenoid value

circuit or loose connector contact

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-II/III actuator test

• Item No. 08: Purge control solenoid valve

OK: Operating sound can be heard and the
valve vibrates

Q: Is the check result normal?

YES :

Intermittent malfunction (Refer to GROUP

00

− How to Use

Troubleshooting/Inspection Service Points

P.00-5

).

NO :

Go to Step 2 .

STEP 2. Connector check: B-02 purge control
solenoid valve connector

Q: Is the check result normal?

YES :

Go to Step 3 .

NO :

Repair or replace the connector.

STEP 3. Perform resistance measurement at B-02
purge control solenoid valve connector.

• Disconnect connector, and measure at solenoid

valve side.

• Resistance between terminal No. 1 and No. 2.

OK: 30

− 34 Ω (at 20°C)

Q: Is the check result normal?

YES :

Go to Step 4 .

NO :

Replace the purge control solenoid valve.

STEP 4. Perform voltage measurement at B-02
purge control solenoid valve connector.

• Disconnect connector, and measure at harness

side.

• Ignition switch: "ON"

• Voltage between terminal No. 2 and earth.

OK: System voltage

Q: Is the check result normal?

YES :

Go to Step 6 .

NO :

Go to Step 5 .

AK305025

1

2

AB

Connector : B-02

Harness side
connector

B-02(B)

AK305025

1

2

AB

Connector : B-02

Harness side
connector

B-02(B)

AK305025

1

2

AB

Connector : B-02

Harness side
connector

B-02(B)

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-184

STEP 5. Connector check: B-12X engine control
relay connector.

Q: Is the check result normal?

YES :

Check and repair harness between B-02

(terminal No. 2) purge control solenoid valve
connector and B-12X (terminal No. 4)
engine control relay connector.

• Check power line for open/short

circuit.

NO :

Repair or replace the connector.

STEP 6. Perform voltage measurement at C-121
engine-ECU connector.

• Disconnect connector, and measure at harness

side.

• Ignition switch: "ON"

• Voltage between terminal No. 16 and earth.

OK: System voltage

Q: Is the check result normal?

YES :

Go to Step 8 .

NO :

Go to Step 7 .

AK305003

2

1

3

4

AB

Connector : B-12X

B-12X

Harness side
connector

Relay box’s
triangle marks

AK305025

1

2

AB

Connector : B-02

Harness side
connector

B-02(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>

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-185

STEP 7. Connector check: C-121 engine-ECU
connector

Q: Is the check result normal?

YES :

Check and repair harness between B-02

(terminal No. 1) purge control solenoid valve
connector and C-121 (terminal No. 16)
engine-ECU connector.

• Check output line for open/short

circuit.

NO :

Repair or replace the connector.

STEP 8. Connector check: C-121 engine-ECU
connector

Q: Is the check result normal?

YES :

Go to Step 9 .

NO :

Repair or replace the connector.

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>

AK305025

1

2

AB

Connector : B-02

Harness side
connector

B-02(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>

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI)

13A-186

STEP 9. Check harness between B-02 (terminal
No. 1) purge control solenoid valve connector
and C-121 (terminal No. 16) engine-ECU
connector.

• Check output line for damage.

Q: Is the check result normal?

YES :

Go to Step 10 .

NO :

Repair the damaged harness wire.

STEP 10. Check harness between B-02 (terminal
No. 2) purge control solenoid valve connector
and B-12X (terminal No. 4) engine control relay
connector.

• Check power supply line for damage.

Q: Is the check result normal?

YES :

Go to Step 11 .

NO :

Repair the damaged harness wire.

STEP 11. M.U.T.-II/III actuator test

• Item No. 08: purge control solenoid valve

OK: Operating sound can be heard and the
valve vibrates.

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.

AK305025

1

2

AB

Connector : B-02

Harness side
connector

B-02(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>

AK305025

1

2

AB

Connector : B-02

Harness side
connector

B-02(B)

AK305003

2

1

3

4

AB

Connector : B-12X

B-12X

Harness side
connector

Relay box’s
triangle marks