Subaru Legacy 2003 Service Manual page 2064

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Step
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?
2 CHECK POOR CONTACT.
Check poor contact in ECM connector.
Is there poor contact in ECM connector?
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?
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?
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?
Value
10 V
There is poor contact.
10 V
1 Ω
There are poor contacts.
EN(H4DOSTC)-225
ENGINE (DIAGNOSTICS)
Yes
Go to step 3. Go to step 2.
Repair the poor Replace the ECM.
contact in ECM <Ref. to
connector. FU(H4DOSTC)-
40, Engine Con-
trol Module.>
Repair the battery Go to step 4.
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.>
Replace the relief Go to step 5.
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.>
Repair the poor Replace the ECM.
contact in ECM <Ref. to
connector. FU(H4DOSTC)-
40, Engine Con-
trol Module.>
No