Subaru Legacy III (2000-2003 year). Manual - part 513

EN(H4DOSTC)-222

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

6

CHECK POOR CONTACT.
Check poor contact in relief valve control sole-
noid valve 1 and ECM connectors.
Are there poor contact in relief valve control 
solenoid valve 1 and ECM connectors?

There are poor contacts.

Repair the poor 
contact in relief 
valve control sole-
noid valve 1 and 
ECM connectors.

Contact SUBARU 
distributor service.

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

Step

Value

Yes

No

EN(H4DOSTC)-223

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

MEMO:

EN(H4DOSTC)-224

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

BG:DTC P1248 — RELIEF VALVE CONTROL SOLENOID VALVE 1 CIRCUIT 

HIGH —

• TROUBLE SYMPTOM:

• Poor driving performance

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-00939

B220

B47

E

BATTERY

MAIN RELAY

3

B136

ECM

SBF-5

5

2
1

4

6

B47

3

4

1

2

5

6

B220

SOLENOID 
BOX ASSY

1

2

3

4

5

6

7

8

9

10

11

12

(A)

(B)

(C)

(D)

(E)

(F)

(A): RELIEF VALVE SOLENOID 2
(B): RELIEF VALVE SOLENOID 1
(C): EXHAUST VALVE CONTROL SOLENOID VALVE
       (NEGATIVE PRESSURE)
(D): EXHAUST VALVE CONTROL SOLENOID VALVE
       (POSITIVE PRESSURE)
(E): INTAKE AIR CONTROL SOLENOID VALVE
(F): EXHAUST VALVE CONTROL DUTY SOLENOID VALVE

C:

B137

D:

C11

C12

C3

C1

D22

D11

1 2 3 4
5 6 7 8
9 10 11 12

B136

1 2

7

8 9

5

6

3

4

10 11 12
19 20 21

13 14 15 16

17 18

22 23 24

B137

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

EN(H4DOSTC)-225

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

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

chassis ground.

Connector & terminal

(B136) No. 12 (+) — Chassis ground (

−−−−

):

Does the measured value exceed the spec-
ified value?

10 V

Go to step 3.

Go to step 2.

2

CHECK POOR CONTACT.
Check poor contact in ECM connector. 
Is there poor contact in ECM connector?

There is poor contact.

Repair the poor 
contact in ECM 
connector.

Replace the ECM.  
<Ref. to 
FU(H4DOSTC)-
40, Engine Con-
trol Module.>

3

CHECK HARNESS BETWEEN RELIEF 
VALVE CONTROL SOLENOID VALVE 1 AND 
ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from relief valve 

control solenoid valve 1.

3) Turn the ignition switch to ON.
4) Measure the voltage between ECM and 

chassis ground.

Connector & terminal

(B136) No. 12 (+) — Chassis ground (

−−−−

):

Does the measured value exceed the spec-
ified value?

10 V

Repair the battery 
short circuit in har-
ness between 
ECM and relief 
valve control sole-
noid valve 1 con-
nector. After 
repair, replace the 
ECM.  <Ref. to 
FU(H4DOSTC)-
40, Engine Con-
trol Module.>

Go to step 4.

4

CHECK RELIEF VALVE CONTROL SOLE-
NOID VALVE 1.
1) Turn the ignition switch to OFF.
2) Measure the resistance between relief 

valve control solenoid valve 1 terminals.

Terminals

No. 3 — No. 4:

Is the measured value less than the speci-
fied value?

1 

Ω

Replace the relief 
valve control sole-
noid valve 1 <Ref. 
to IN(H4DOSTC)-
19, Solenoid Box 
Assembly.> and 
replace ECM.  
<Ref. to 
FU(H4DOSTC)-
40, Engine Con-
trol Module.>

Go to step 5.

5

CHECK POOR CONTACT.
Check poor contact in ECM and relief valve 
control solenoid valve 1 connetors.
Are there poor contact in ECM and relief valve 
control solenoid valve 1 connetors?

There are poor contacts.

Repair the poor 
contact in ECM 
connector.

Replace the ECM.  
<Ref. to 
FU(H4DOSTC)-
40, Engine Con-
trol Module.>