Subaru Legacy III (2000-2003 year). Service manual — part 487

EN(H4DOSTC)-118

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

R: DTC P0245 — TURBO/SUPER CHARGERWASTEGATESOLENOID “A” LOW

—

• TROUBLE SYMPTOM:

• Erroneous idling

CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(H4DOSTC)-35,
OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4DOSTC)-33, Inspection
Mode.> .
• WIRING DIAGRAM:

EN-00938

MAIN RELAY

B47

1

2

3

5

4

6

BATTERY

E

B47

B137

F81

F44

B137

F81

WASTEGATE
CONTROL SOLENOID
VALVE

ECM

24

1

2

SBF-5

3

4

1

2

5

6

1

2

7

8

9

5

6

3

4

10 11 12

19 20 21
29 30 31

13 14 15 16 17

27 28

18

22 23 24 25 26

1 2

B62

F45

B62

B61

F44

1

5

21

9

32

1 2 3 4

5 6

10 11 12 13 14 15

7

16

23

30

19 20

22

26 27 28 29

8

17

24

31

18

25

1 2

3

4 5 6 7 8

EN(H4DOSTC)-119

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK OUTPUT SIGNAL FROM ECM.
1) Turn the ignition switch to ON.
2) Measure the voltage between ECM and

chassis ground.

Connector & terminal

(B137) No. 24 (+) — Chassis ground (

−−−−

):

Does the measured value exceed the spec-
ified value?

10 V

Even if MI lights
up, the circuit has
returned to a nor-
mal condition at
this time. Contact
with your Subaru
distributor.

NOTE:
Inspection by DTM
is required, be-
cause probable
cause is deteriora-
tion of multiple
parts.

Go to step 2.

2

CHECK HARNESS BETWEEN WASTEGATE
CONTROL SOLENOID VALVE AND ECM
CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from wastegate

control solenoid valve and ECM.

3) Measure the resistance of harness

between wastegate control solenoid valve
connector and engine ground.

Connector & terminal

(F81) No. 1 — Engine ground:

Does the measured value exceed the spec-
ified value?

1 M

Ω

Go to step 3.

Repair the ground
short circuit in har-
ness between
ECM and waste-
gate control sole-
noid valve
connector.

3

CHECK HARNESS BETWEEN WASTEGATE
CONTROL SOLENOID VALVE AND ECM
CONNECTOR.
Measure the resistance of harness between
ECM and wastegate control solenoid valve of
harness connector.

Connector & terminal

(B137) No. 24 — (F81) No. 1:

Is the measured value less than the specified
value?

1

Ω

Go to step 4.

Repair the open
circuit in harness
between ECM and
wastegate control
solenoid valve
connector.

NOTE:
In this case, repair
the following:
• Open circuit in
harness between
ECM and waste-
gate control sole-
noid valve
connector

4

CHECK WASTEGATE CONTROL SOLE-
NOID VALVE.
1) Remove the wastegate control solenoid

valve.

2) Measure the resistance between wastegate

control solenoid valve terminals.

Terminals

No. 1 — No. 2:

Is the measured value within the specified
value?

30 — 34

Ω

Go to step 5.

Replace the
wastegate control
solenoid valve.
<Ref. to
IN(H4DOSTC)-21,
Wastegate Con-
trol Solenoid
Valve.>

EN(H4DOSTC)-120

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

5

CHECK POWER SUPPLY TO WASTEGATE
CONTROL SOLENOID VALVE.
1) Turn the ignition switch to ON.
2) Measure the voltage between wastegate

control solenoid valve and engine ground.

Connector & terminal

(F81) No. 2 (+) — Engine ground (

−−−−

):

Does the measured value exceed the spec-
ified value?

10 V

Go to step 6.

Repair the open
circuit in harness
between main
relay and waste-
gate control sole-
noid valve
connector.

6

CHECK POOR CONTACT.
Check poor contact in wastegate control sole-
noid valve connector.
Is there poor contact in wastegate control sole-
noid valve connector?

There is poor contact.

Repair the poor
contact in waste-
gate control sole-
noid valve
connector.

Contact with your
Subaru distributor.

NOTE:
Inspection by DTM
is required, be-
cause probable
cause is deteriora-
tion of multiple
parts.

Step

Value

Yes

No

EN(H4DOSTC)-121

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

MEMO: