Subaru Impreza 2003 Service Manual page 506

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
Step
1 CHECK OUTPUT SIGNAL FROM ECM.
1)Turn ignition switch to ON.
2)Measure voltage between ECM and chassis
ground.
Connector & terminal
(B134) No. 12 (+) — Chassis ground ( − − − − ):
2 CHECK OUTPUT SIGNAL FROM ECM.
1)Turn ignition switch to OFF.
2)Disconnect connector from air assist injector
solenoid valve.
3)Turn ignition switch to ON.
4)Measure voltage between ECM and chassis
ground.
Connector & terminal
(B134) No. 12 (+) — Chassis ground ( − − − − ):
3 CHECK OUTPUT SIGNAL FROM ECM.
Measure voltage between ECM and chassis
ground.
Connector & terminal
(B134) No. 12 (+) — Chassis ground ( − − − − ):
Check
Is the voltage more than 10 V? Go to step 2.
Is the voltage more than 10 V? Repair battery
Does the voltage change by
shaking the ECM harness and
connector?
EN(H4SO)-94
Yes
Go to step 3.
Replace air assist
short circuit in har- injector solenoid
ness between valve <Ref. to
ECM and air assist FU(H4SO)-37, Air
injector solenoid Assist Injector
valve connector. Solenoid Valve.>
After repair, and ECM <Ref. to
replace ECM. FU(H4SO)-48,
<Ref. to Engine Control
FU(H4SO)-48, Module (ECM).>
Engine Control
Module (ECM).>
Repair battery Contact with your
short circuit in har- Subaru distributor
ness between service.
ECM and air assist
NOTE:
injector solenoid
Inspection by DTM
valve connector.
is required,
After repair,
cause
replace ECM.
cause is deteriora-
<Ref. to
tion of
FU(H4SO)-48,
parts.
Engine Control
Module (ECM).>
No
be-
probable
multiple