Subaru Legacy IV (2008 year). Service manual — part 354

EN(H4DOTC)(diag)-237

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BU:DTC P0459 EVAPORATIVE EMISSION SYSTEM PURGE CONTROL VALVE

CIRCUIT HIGH

DTC DETECTING CONDITION:
• Two consecutive driving cycles with fault
• GENERAL DESCRIPTION <Ref. to GD(H4DOTC)-136, DTC P0459 EVAPORATIVE EMISSION SYS-
TEM PURGE CONTROL VALVE CIRCUIT HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>
TROUBLE SYMPTOM:
Improper idling

CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode <Ref. to EN(H4DOTC)(diag)-
52, OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4DOTC)(diag)-43, PRO-
CEDURE, Inspection Mode.>.
WIRING DIAGRAM:

EN-05679

SBF-7

E4

B47

E

5
3

6
4

2
1

2

1

C17

C28

D29

C7

R15

R213

R68

R144

R1

B97

14

15

2

2

1

1

7

1

5

E52

2

1

E52

R144

E4

B47

R67

B97

R213

R68

1 2

3

4

1

2

5

6

B21

1 2

1 2

3

4 5 6 7 8

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

1

2

3 4 5 6

1 2 3 4

5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

R46

R67

6

B21

E2

11

48

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:

B137

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

D:

B136

C:

B137

D:

44

MAIN RELAY

ECM

BATTERY

DRAIN VALVE

PRESSURE

CONTROL

SOLENOID VALVE

PURGE CONTROL

SOLENOID VALVE 1

PURGE CONTROL

SOLENOID VALVE 2

EN(H4DOTC)(diag)-238

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step

Check

Yes

No

1

OPEN CIRCUIT IN HARNESS BETWEEN
ECM AND PURGE CONTROL SOLENOID
VALVE.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM and
purge control solenoid valve.
3) Turn the ignition switch to ON.
4) Measure the voltage between ECM and
chassis ground.

Connector & terminal

(B137) No. 29 (+) — Chassis ground (–):

Is the voltage 10 V or more?

Repair the short
circuit to power in
the harness
between ECM and
purge control sole-
noid valve connec-
tor.

Go to step 2.

2

CHECK PURGE CONTROL SOLENOID
VALVE.
1) Turn the ignition switch to OFF.
2) Measure the resistance between purge con-
trol solenoid valve terminals.

Terminals

No. 1 — No. 2:

Is the resistance less than 1

:? Replace the purge

control solenoid
valve. <Ref. to
EC(H4DOTC)-9,
Purge Control
Solenoid Valve.>

Repair the poor
contact of ECM
connector.

EN(H4DOTC)(diag)-239

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BV:DTC P0461 FUEL LEVEL SENSOR “A” CIRCUIT RANGE/PERFORMANCE

DTC DETECTING CONDITION:
• Two consecutive driving cycles with fault
• GENERAL DESCRIPTION <Ref. to GD(H4DOTC)-138, DTC P0461 FUEL LEVEL SENSOR “A” CIRCUIT
RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode <Ref. to EN(H4DOTC)(diag)-
52, OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4DOTC)(diag)-43, PRO-
CEDURE, Inspection Mode.>.

BW:DTC P0462 FUEL LEVEL SENSOR “A” CIRCUIT LOW

NOTE:
For the diagnostic procedure, refer to DTC P0463. <Ref. to EN(H4DOTC)(diag)-239, DTC P0463 FUEL LEV-
EL SENSOR “A” CIRCUIT HIGH, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

BX:DTC P0463 FUEL LEVEL SENSOR “A” CIRCUIT HIGH

DTC DETECTING CONDITION:
• Two consecutive driving cycles with fault
• GENERAL DESCRIPTION <Ref. to GD(H4DOTC)-142, DTC P0463 FUEL LEVEL SENSOR “A” CIRCUIT
HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode <Ref. to EN(H4DOTC)(diag)-
52, OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4DOTC)(diag)-43, PRO-
CEDURE, Inspection Mode.>.

Step

Check

Yes

No

1

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

Check the appro-
priate DTC using
the “List of Diag-
nostic Trouble
Code (DTC)”.
<Ref. to
EN(H4DOTC)(diag)
-81, List of Diag-
nostic Trouble
Code (DTC).>

Replace the fuel
level sensor and
fuel sub level sen-
sor. <Ref. to
FU(H4DOTC)-72,
Fuel Level Sen-
sor.> <Ref. to
FU(H4DOTC)-73,
Fuel Sub Level
Sensor.>

Step

Check

Yes

No

1

CHECK FOR ANY OTHER DTC ON DISPLAY. Is DTC P0462 or P0463 dis-

played on the Subaru Select
Monitor?

Check the combi-
nation meter. <Ref.
to IDI-13, CHECK
FUEL LEVEL
SENSOR,
INSPECTION,
Combination Meter
System.>

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.

EN(H4DOTC)(diag)-240

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BY:DTC P0464 FUEL LEVEL SENSOR CIRCUIT INTERMITTENT

DTC DETECTING CONDITION:
• Two consecutive driving cycles with fault
• GENERAL DESCRIPTION <Ref. to GD(H4DOTC)-144, DTC P0464 FUEL LEVEL SENSOR CIRCUIT IN-
TERMITTENT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode <Ref. to EN(H4DOTC)(diag)-
52, OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4DOTC)(diag)-43, PRO-
CEDURE, Inspection Mode.>.

BZ:DTC P0500 VEHICLE SPEED SENSOR “A”

DTC DETECTING CONDITION:
• Immediately at fault recognition
• GENERAL DESCRIPTION <Ref. to GD(H4DOTC)-147, DTC P0500 VEHICLE SPEED SENSOR “A”, Di-
agnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode <Ref. to EN(H4DOTC)(diag)-
52, OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4DOTC)(diag)-43, PRO-
CEDURE, Inspection Mode.>.

Step

Check

Yes

No

1

CHECK FOR ANY OTHER DTC ON DISPLAY. Is DTC P0464 displayed on the

display?

Check the combi-
nation meter. <Ref.
to IDI-13, CHECK
FUEL LEVEL
SENSOR,
INSPECTION,
Combination Meter
System.>

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.

Step

Check

Yes

No

1

CHECK DTC OF ABS OR VDC.
Check DTC of ABS or VDC.

Is DTC of ABS or VDC dis-
played?

Perform the diag-
nosis according to
DTC. <Ref. to
ABS(diag)-29, List
of Diagnostic Trou-
ble Code (DTC).>
<Ref. to
VDC(diag)-34, List
of Diagnostic Trou-
ble Code (DTC).>

Repair the poor
contact of ECM
connector.