Subaru Legacy 2003 Service Manual page 2080

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Step
1 CHECK OUTPUT SIGNAL FROM ECM.
1) Start engine, and warm-up the engine.
2) Turn ignition switch to OFF.
3) Disconnect connector from TCM.
4) Turn ignition switch to ON.
5) Measure voltage between ECM and chas-
sis ground.
Connector & terminal
(B136) No. 14 (+) — Chassis ground ( − − − − ):
Is the measured value less than the speci-
fied value?
2 CHECK HARNESS BETWEEN ECM AND
TCM CONNECTOR.
1) Turn ignition switch to OFF.
2) Measure voltage between ECM and chas-
sis ground.
Connector & terminal
(B136) No. 14 (+) — Chassis ground ( − − − − ):
Does the measured value exceed the spec-
ified value by shaking harness and connec-
tor of ECM while monitoring the value with
voltage meter?
Value
3 V
10 V
EN(H4DOSTC)-241
ENGINE (DIAGNOSTICS)
Yes
Go to step 2. Repair battery
short circuit in har-
ness between
ECM and TCM
connector. After
repair, replace
ECM. <Ref. to
FU(H4DOSTC)-
40, Engine Con-
trol Module.>
Repair battery Contact SUBARU
short circuit in har- distributor service.
ness between
NOTE:
ECM and TCM
Inspection by DTM
connector. After
is required,
repair, replace
cause
ECM. <Ref. to
cause is deteriora-
FU(H4DOSTC)-
tion of
40, Engine Con-
parts.
trol Module.>
No
be-
probable
multiple