Subaru Legacy III (2000-2003 year). Manual — part 137

EN(H4SO)-160

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Z: DTC P0139 — O2 SENSOR CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 2)

—

• DTC DETECTING CONDITION:

• Two consecutive driving cycles with fault

CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode<Ref. to EN(H4SO)-47, OPER-
ATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4SO)-40, OPERATION, Inspection
Mode.> .
• WIRING DIAGRAM:

EN-01122

BATTERY

F44

B61

6

T5

B19

2

B47

MAIN RELAY

1

2

3

5

4

6

F44

1 2 3 4
5 6 7 8

C4

B14

B19

D15

C16

C5

REAR

OXYGEN SENSOR

ECM

4

1

3

1

4

3

2

8

B22

B83

B19

T5

T6

E3

B47

B19

B22

1 2 3 4
5 6 7 8
9 10 11 12

13 14 15 16

3

4

5

6

1

2

T6

4 3

2 1

2

1

FG

3

B135

B:

C: B136

D: B137

SBF-5

B136

5 6

7

2

1

9

8

4

3

23

21 22

24

10 11 12 13 14

25 26

15 16 17

18 19 20

B137

4

1
5

3

2
6

18

15

16

7 8 9 10 11

17

19 20

12 13

14

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

B135

B83

1 2 3 4 5 6

4

EG

: FOR G.C.C COUNTRIES MODEL

: EXCEPT FOR G.C.C COUNTRIES MODEL

FG

EG

EN(H4SO)-161

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK ANY OTHER DTC ON DISPLAY.
Is any other DTC displayed?

DTC indicated.

Inspect the rele-
vant DTC using
“List of Diagnostic
Trouble Code
(DTC)”. <Ref. to
EN(H4SO)-83, List
of Diagnostic
Trouble Code
(DTC).>

NOTE:
In this case, it is
not necessary to
inspect DTC
P0139.

Replace rear oxy-
gen sensor. <Ref.
to FU(H4SO)-43,
Rear Oxygen Sen-
sor.>

EN(H4SO)-162

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

AA:DTC P0171 — SYSTEM TOO LEAN (BANK 1) —

NOTE:
For the diagnostic procedure, refer to DTC P0172. <Ref. to EN(H4SO)-164, DTC P0172 — SYSTEM TOO
RICH (BANK 1) —, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

EN(H4SO)-163

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

MEMO: