Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 282

EN(H4DOTC)(diag)-352

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE LH
CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM and
oil flow control solenoid valve LH.
3) Measure the voltage between ECM connec-
tor and chassis ground.

Connector & terminal

(B134) No. 5 (+) — Chassis ground (–):
(B134) No. 14 (+) — Chassis ground (–):

Is the voltage less than 1 V?

Go to step

2.

Repair the short
circuit to power in
harness between
ECM connector
and oil flow control
solenoid valve LH
connector.

2

CHECK HARNESS BETWEEN ECM AND OIL
FLOW CONTROL SOLENOID VALVE LH
CONNECTOR.
Measure the resistance of harness between
ECM connector and oil flow control solenoid
valve LH connector.

Connector & terminal

(B134) No. 5 — (E66) No. 1:
(B134) No. 14 — (E66) No. 2:

Is the resistance less than 1 Ω? Go to step

3.

Repair the harness
and connector.
NOTE:

In this case, repair
the following item:
• Open circuit in
harness between
ECM

connector

and oil flow control
solenoid valve LH
connector
• Poor contact of
coupling connector

3

CHECK OIL FLOW CONTROL SOLENOID
VALVE.
Measure the resistance between oil flow control
solenoid valve terminals.

Terminals

No. 1 — No. 2:

Is the resistance 6 — 12 Ω?

Repair the poor
contact of ECM
and oil flow control
solenoid valve LH
connector.

Replace the oil
flow control sole-
noid valve LH.
<Ref. to FU(STI)-
50, Oil Flow Con-
trol Solenoid
Valve.>

EN(H4DOTC)(diag)-353

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EK:DTC P2096 POST CATALYST FUEL TRIM SYSTEM TOO LEAN (BANK 1)

DTC DETECTING CONDITION:

• Detected when 2 consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(H4DOTC)-239, DTC P2096 POST CATALYST FUEL TRIM SYS-

TEM TOO LEAN (BANK 1), 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:

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

System.>

ECM

B138

6

4 5

3

2

1

E22

1

2

3

15

43

26

B21

E2

44

2

E2

B21

1 2
3 4

E22

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

2

1

B220

15A

9

10

11
12

B220

D:

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

C: B136

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

*

*

*

B138

D1

36

A4

40

34

35

B21

E2

D3

A6

A3

A:

54

52 53

50 51

48 49

46 47

45

44

42 43

40 41

38 39

36 37

34 35

33

32

31

30

29

28

27

26

25

24

23

22

21

20

11

10

9

19

18

17

16

8

7

6

5

15

14

13

12

4

3

2

1

D: B137

C: B136

A:

31

30

32

29

34

33

21

20

19

18

17

16

28

27

26

15

14

13

12

11

25

23

22

24

10

3

4

9

1

2

8

7

6

5

B134

B21

B134

C9

C19

C1

8

C6

C5

EN-08720

E

E

E

SBF-5

BATTERY

: TERMINAL No. OPTIONAL ARRANGEMENT

A/F, OXYGEN SENSOR

RELAY

FUSE

(RELAY BLOCK)

FRONT OXYGEN (A/F)

SENSOR

EN(H4DOTC)(diag)-354

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

ECM

6

4 5

3

2

1

*

2

1

B220

15A

9

10

11
12

B220

*

*

1 2
3 4

D1

36

A4

40

34

35

B21

E2

D3

A6

A3

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

B134

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

33 34

29

32

30 31

A:

D: B137

C: B136

B: B135

A:

T6

B134

C9

B30

C20

B6

*

*

B21

1 2 3 4

12 13 14 15

5 6 7 8

16 17 18 19

9 10 11

20 21 22

23 24 25 26 27 28 29 30 31 32 33

35

34

37

36

39

38

41

40

43

42

44 45

47

46

49

48

51

50

53

52

54

4

1

3

4

1

3

B19

T5

22

T5

B19

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

B135

B:

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

B136

C:

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

33 34

29

32

30

31

35

D: B137

B19

T6

B83

B138

B138

B83

EN-08722

E

E

SBF-5

BATTERY

: TERMINAL No. OPTIONAL ARRANGEMENT

REAR

OXYGEN SENSOR

A/F, OXYGEN SENSOR

RELAY

FUSE

(RELAY BLOCK)

EN(H4DOTC)(diag)-355

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

• Models with SI-DRIVE <Ref. to WI-48, WITH SI-DRIVE, WIRING DIAGRAM, Engine Electrical System.>

ECM

B138

6

4 5

3

2

1

1

2

3

4

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

2

1

B220

15A

9

10

11
12

B220

D:

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

C: B136

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

*

*

*

B138

D1

36

D3

A4

40

34

35

B21

E2

A6

A3

A:

54

52 53

50 51

48 49

46 47

45

44

42 43

40 41

38 39

36 37

34 35

33

32

31

30

29

28

27

26

25

24

23

22

21

20

11

10

9

19

18

17

16

8

7

6

5

15

14

13

12

4

3

2

1

D: B137

C: B136

A:

31

30

32

29

34

33

21

20

19

18

17

16

28

27

26

15

14

13

12

11

25

23

22

24

10

3

4

9

1

2

8

7

6

5

B134

B379

B21

B379

4

2

3

1

B134

C9

C19

C1

8

C6

C5

EN-08721

SBF-5

E

E

FRONT OXYGEN (A/F)

SENSOR

BATTERY

: TERMINAL No. OPTIONAL ARRANGEMENT

A/F, OXYGEN SENSOR

RELAY

FUSE

(RELAY BLOCK)