Subaru Legacy (2005 year). Manual - part 130

EN(H4SO 2.0)(diag)-109

ENGINE (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

Q: DTC P0132 O2 SENSOR CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 1)

DTC DETECTING CONDITION:
Immediately at fault recognition

CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode <Ref. to EN(H4SO 2.0)(diag)-
38, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4SO 2.0)(diag)-32, PRO-
CEDURE, Inspection Mode.>.
WIRING DIAGRAM:

EN-03475

3

4

1

2

5

6

B47

SBF-5

E

B47

E24

5
3

4
6

2
1

C34

C35

C33

B3

B2

B1

B135

E

B5

B6

52

B21

E2

B21

E2

50

51

3

4

E2

B21

E

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

E24

ECM

BATTERY

FRONT OXYGEN

(A/F) SENSOR

MAIN RELAY

B136

B:

C:

1

2

3

4

B135

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

B:

B136

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

C:

E24

3

2

*

1

*

*

3

  LHD : 4

RHD : 1

*

1

*

*

2

3

3

1

6 5 4

2

: RHD

: LHD

LHD : 1

RHD : 4

LHD : 2

RHD : 6

EN(H4SO 2.0)(diag)-110

ENGINE (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

Step

Check

Yes

No

1

CHECK HARNESS BETWEEN ECM AND 
FRONT OXYGEN (A/F) SENSOR CONNEC-
TOR.
1) Turn the ignition switch to ON.
2) Disconnect the connector from front oxygen 
(A/F) sensor.
3) Measure the voltage of harness between 
ECM connector and chassis ground.

Connector & terminal

(B136) No. 33 (+) — Chassis ground (

−

):

(B136) No. 35 (+) — Chassis ground (

−

):

Is the voltage more than 8 V?

Replace the front 
oxygen (A/F) sen-
sor. <Ref. to 
FU(H4SO 2.0)-32, 
Front Oxygen (A/
F) Sensor.>

Repair the battery 
short circuit of har-
ness between 
ECM and front 
oxygen (A/F) sen-
sor connector.

EN(H4SO 2.0)(diag)-111

ENGINE (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

R: DTC P0133 O2 SENSOR CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 1)

DTC DETECTING CONDITION:
Detects when malfunction occurs in 2 continuous driving cycles.

CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode <Ref. to EN(H4SO 2.0)(diag)-
38, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4SO 2.0)(diag)-32, PRO-
CEDURE, Inspection Mode.>.
WIRING DIAGRAM:

EN-03475

3

4

1

2

5

6

B47

SBF-5

E

B47

E24

5
3

4
6

2
1

C34

C35

C33

B3

B2

B1

B135

E

B5

B6

52

B21

E2

B21

E2

50

51

3

4

E2

B21

E

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

E24

ECM

BATTERY

FRONT OXYGEN

(A/F) SENSOR

MAIN RELAY

B136

B:

C:

1

2

3

4

B135

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

B:

B136

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

C:

E24

3

2

*

1

*

*

3

  LHD : 4

RHD : 1

*

1

*

*

2

3

3

1

6 5 4

2

: RHD

: LHD

LHD : 1

RHD : 4

LHD : 2

RHD : 6

EN(H4SO 2.0)(diag)-112

ENGINE (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

Step

Check

Yes

No

1

CHECK ANY OTHER DTC ON DISPLAY.

Is any other DTC displayed?

Check DTC using 
“List of Diagnostic 
Trouble Code 
(DTC)”. <Ref. to 
EN(H4SO 
2.0)(diag)-64, List 
of Diagnostic Trou-
ble Code (DTC).>

NOTE:
In this case, it is
not necessary to
inspect DTC
P0133.

Go to step 2.

2

CHECK EXHAUST SYSTEM.

NOTE:

Check the following items.
• Loose installation of front portion of exhaust 
pipe onto cylinder heads
• Loose connection between front exhaust 
pipe and front catalytic converter
• Damage of exhaust pipe resulting in a hole

Is there any fault in exhaust 
system?

Repair the exhaust 
system.

Replace the front 
oxygen (A/F) sen-
sor. <Ref. to 
FU(H4SO 2.0)-32, 
Front Oxygen (A/
F) Sensor.>