Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 300

EN(H4DOTC)(diag)-424

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

6

CHECK LEAK CHECK VALVE ASSEMBLY.
Check the vacuum pump of the leak check
valve assembly. <Ref. to EC(STI)-21, CHECK
VACUUM PUMP, INSPECTION, Leak Check
Valve Assembly.> <Ref. to EC(w/o STI)-22,
CHECK VACUUM PUMP, INSPECTION, Leak
Check Valve Assembly.>

Is the vacuum pump of the leak
check valve assembly OK?

Repair the poor
contact in the leak
check valve
assembly connec-
tor.

Replace the leak
check valve
assembly. <Ref. to
EC(STI)-19, Leak
Check Valve
Assembly.> <Ref.
to EC(w/o STI)-20,
Leak Check Valve
Assembly.>

Step

Check

Yes

No

EN(H4DOTC)(diag)-425

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FD:DTC P2402 EVAPORATIVE EMISSION SYSTEM LEAK DETECTION PUMP

CONTROL CIRCUIT HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(H4DOTC)-278, DTC P2402 EVAPORATIVE EMISSION SYS-

TEM LEAK DETECTION PUMP CONTROL CIRCUIT HIGH, Diagnostic Trouble Code (DTC) Detecting Cri-

teria.>
CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(H4DOTC)(diag)-63,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4DOTC)(diag)-49, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine electrical system, without SI-DRIVE <Ref. to WI-32, WITHOUT SI-DRIVE, WIRING DIAGRAM,

Engine Electrical System.>

• Engine electrical system, with SI-DRIVE <Ref. to WI-48, WITH SI-DRIVE, WIRING DIAGRAM, Engine

Electrical System.>

ECM

B97

R1

10

B92

2 3 4 5

6 7 8 9

11 12 13 14

17 18 19 20

1

10

15 16

B97

R82

1 2

3 4 5

6 7 8 9 10 11 12

B220

B83

4

1 2 3

6

5

*

B83

*

*

D27

B22

C21

B30

B4

B135

B:

B136

C:

B137

D:

14

17

15

16

13

8

R81

R82

1

5

8

7

6

4

3

R400

5

6

7

8

2

1

9

4

3

10

24

22 23

25

11 12 13 14 15

26 27

28

16 17 18 19

20 21

29 30 31

32 33

34 35

B135

B:

5

6

7

8

2

1

9

4

3

10

22 23

11 12 13 14 15

24 25

26

16 17

18 19 20 21

27

28 29

30 31

B137

D:

16

10 11 12 13 14 15

25

24

30

9

8

7

17 18 19 20
28

21 22 23

29

32

31

1

2

3

4

5

6

27

26

33 34 35

B136

C:

1 2

4

5 6 7 8

3

R400

24

23

22

21

B220

13
14

15 16

17

27

24

25
26

20

21
22

23

29
30

31

28

32 35

33
34

37
38

39

36

40

8

9

10

11 12

1

2

5

3

4

7

6

19

18

B220

4

3

EN-09250

R5

B92

E

SBF-7

BATTERY

FUSE

(RELAY BLOCK)

MAIN RELAY

LEAK CHECK VALVE ASSY

VACUUM

PUMP

PRESSURE

SENSOR

SWITCHING

VALVE

: TERMINAL No. OPTIONAL ARRANGEMENT

EN(H4DOTC)(diag)-426

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK HARNESS BETWEEN ECM AND
LEAK CHECK VALVE ASSEMBLY CONNEC-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from the leak
check valve assembly.
3) Turn the ignition switch to ON.
4) Measure the voltage between leak check
valve assembly and chassis ground.

Connector & terminal

(R400) No. 4 (+) — Chassis ground (–):

Is the voltage 10 V or more?

Repair the short
circuit to power in
harness between
ECM connector
and leak check
valve assembly
connector.

Go to step

2.

2

CHECK LEAK CHECK VALVE ASSEMBLY.
1) Turn the ignition switch to OFF.
2) Check the vacuum pump of the leak check
valve assembly. <Ref. to EC(STI)-21, CHECK
VACUUM PUMP, INSPECTION, Leak Check
Valve Assembly.> <Ref. to EC(w/o STI)-22,
CHECK VACUUM PUMP, INSPECTION, Leak
Check Valve Assembly.>

Is the vacuum pump of the leak
check valve assembly OK?

Repair the poor
contact in the leak
check valve
assembly connec-
tor.

Replace the leak
check valve
assembly. <Ref. to
EC(STI)-19, Leak
Check Valve
Assembly.> <Ref.
to EC(w/o STI)-20,
Leak Check Valve
Assembly.>

EN(H4DOTC)(diag)-427

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FE:DTC P2404 EVAPORATIVE EMISSION SYSTEM LEAK DETECTION PUMP

SENSE CIRCUIT RANGE/PERFORMANCE

DTC DETECTING CONDITION:

• Detected when 2 consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(H4DOTC)-279, DTC P2404 EVAPORATIVE EMISSION SYS-

TEM LEAK DETECTION PUMP SENSE CIRCUIT RANGE/PERFORMANCE, Diagnostic Trouble Code

(DTC) Detecting Criteria.>
CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(H4DOTC)(diag)-63,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4DOTC)(diag)-49, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine electrical system, without SI-DRIVE <Ref. to WI-32, WITHOUT SI-DRIVE, WIRING DIAGRAM,

Engine Electrical System.>

• Engine electrical system, with SI-DRIVE <Ref. to WI-48, WITH SI-DRIVE, WIRING DIAGRAM, Engine

Electrical System.>

ECM

B97

R1

10

B92

2 3 4 5

6 7 8 9

11 12 13 14

17 18 19 20

1

10

15 16

B97

R82

1 2

3 4 5

6 7 8 9 10 11 12

B220

B83

4

1 2 3

6

5

*

B83

*

*

D27

B22

C21

B30

B4

B135

B:

B136

C:

B137

D:

14

17

15

16

13

8

R81

R82

1

5

8

7

6

4

3

R400

5

6

7

8

2

1

9

4

3

10

24

22 23

25

11 12 13 14 15

26 27

28

16 17 18 19

20 21

29 30 31

32 33

34 35

B135

B:

5

6

7

8

2

1

9

4

3

10

22 23

11 12 13 14 15

24 25

26

16 17

18 19 20 21

27

28 29

30 31

B137

D:

16

10 11 12 13 14 15

25

24

30

9

8

7

17 18 19 20
28

21 22 23

29

32

31

1

2

3

4

5

6

27

26

33 34 35

B136

C:

1 2

4

5 6 7 8

3

R400

24

23

22

21

B220

13
14

15 16

17

27

24

25
26

20

21
22

23

29
30

31

28

32 35

33
34

37
38

39

36

40

8

9

10

11 12

1

2

5

3

4

7

6

19

18

B220

4

3

EN-09250

R5

B92

E

SBF-7

BATTERY

FUSE

(RELAY BLOCK)

MAIN RELAY

LEAK CHECK VALVE ASSY

VACUUM

PUMP

PRESSURE

SENSOR

SWITCHING

VALVE

: TERMINAL No. OPTIONAL ARRANGEMENT