Subaru Legacy IV (2008 year). Manual - part 561

EN(H6DO)(diag)-217

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK HARNESS BETWEEN ECM AND 
KNOCK SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM.
3) Measure the resistance between ECM con-
nectors.

Connector & terminal

(B134) No. 15 — (B134) No. 29:

Is the resistance 600 k

: or 

more?

Go to step 2.

Repair the poor 
contact of ECM 
connector.

2

CHECK KNOCK SENSOR.
1) Disconnect the connector from knock sen-
sor.
2) Measure the resistance between knock 
sensor terminals.

Terminals

No. 1 — No. 2:

Is the resistance 600 k

: or 

more?

Replace the knock 
sensor. <Ref. to 
FU(H6DO)-23,
Knock Sensor.>

Repair the harness 
and connector.

NOTE:
In this case, repair
the following item:
• Open circuit of
harness between
ECM and knock
sensor
• Poor contact of
the knock sensor
connector
• Poor contact of
coupling connector

EN(H6DO)(diag)-218

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BU:DTC P0328 KNOCK SENSOR 1 CIRCUIT HIGH (BANK 1 OR SINGLE SENSOR)

DTC DETECTING CONDITION:
• Immediately at fault recognition
• GENERAL DESCRIPTION <Ref. to GD(H6DO)-95, DTC P0328 KNOCK SENSOR 1 CIRCUIT HIGH
(BANK 1 OR SINGLE SENSOR), Diagnostic Trouble Code (DTC) Detecting Criteria.>
TROUBLE SYMPTOM:
• Poor driving performance
• Knocking occurs.

CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode <Ref. to EN(H6DO)(diag)-52,
OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H6DO)(diag)-44, PROCEDURE,
Inspection Mode.>.
WIRING DIAGRAM:

EN-06875

B21

1 2 3 4 5 6 7 8 9 10 11

12 13 14 15 16 17 18 19 20 21 22
23 24 25 26 27 28 29 30 31 32 33

34

35

42

43

36

37

38

39

48

49

50

51

52

53

54

40

41

44

45

46

47

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

1 2

1 2 3 4
5 6 7 8
9 10 11 12

13 14 15 16

E

2

1

E14

2

1

E48

13

B20

E1

B21

E2

14

15

25

ECM

B134

16

29

E14

E48

B134

B20

19

KNOCK

SENSOR

2 (LH)

KNOCK

SENSOR

1 (RH)

EN(H6DO)(diag)-219

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK HARNESS BETWEEN ECM AND 
KNOCK SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM.
3) Measure the resistance between ECM con-
nectors.

Connector & terminal

(B134) No. 15 — (B134) No. 29:

Is the resistance less than 
500 k

:?

Go to step 2.

Go to step 3.

2

CHECK KNOCK SENSOR.
1) Disconnect the connector from knock sen-
sor.
2) Measure the resistance between knock 
sensor connectors.

Terminals

No. 1 — No. 2:

Is the resistance less than 
500 k

:?

Replace the knock 
sensor. <Ref. to 
FU(H6DO)-23,
Knock Sensor.>

Repair the short 
circuit to ground in 
harness between 
ECM and knock 
sensor connector.

NOTE:
The harness be-
tween both con-
nectors are
shielded. Remove
the shield and re-
pair the short cir-
cuit of harness.

3

CHECK INPUT SIGNAL OF ECM.
1) Connect the connector to ECM.
2) Turn the ignition switch to ON.
3) Measure the voltage between ECM and 
chassis ground.

Connector & terminal

(B134) No. 15 (+) — Chassis ground (–):

Is the voltage 2 V or more?

Even if DTC is 
detected, the cir-
cuit has returned to 
a normal condition 
at this time. Repro-
duce the failure, 
and then perform 
the diagnosis 
again.

NOTE:
In this case, tem-
porary poor con-
tact of connector
may be the cause.

Repair the poor 
contact of ECM 
connector.

EN(H6DO)(diag)-220

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BV:DTC P0332 KNOCK SENSOR 2 CIRCUIT LOW (BANK 2)

DTC DETECTING CONDITION:
• Immediately at fault recognition
• GENERAL DESCRIPTION <Ref. to GD(H6DO)-96, DTC P0332 KNOCK SENSOR 2 CIRCUIT LOW
(BANK 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>
TROUBLE SYMPTOM:
• Driving performance problem
• Knocking is occurred.

CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode <Ref. to EN(H6DO)(diag)-52,
OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H6DO)(diag)-44, PROCEDURE,
Inspection Mode.>.
WIRING DIAGRAM:

EN-06875

B21

1 2 3 4 5 6 7 8 9 10 11

12 13 14 15 16 17 18 19 20 21 22
23 24 25 26 27 28 29 30 31 32 33

34

35

42

43

36

37

38

39

48

49

50

51

52

53

54

40

41

44

45

46

47

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

1 2

1 2 3 4
5 6 7 8
9 10 11 12

13 14 15 16

E

2

1

E14

2

1

E48

13

B20

E1

B21

E2

14

15

25

ECM

B134

16

29

E14

E48

B134

B20

19

KNOCK

SENSOR

2 (LH)

KNOCK

SENSOR

1 (RH)