Subaru Legacy 2003 Service Manual page 567

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
5 CHECK FUEL INJECTOR.
Measure resistance between fuel injector ter-
minals on faulty cylinder.
Terminals
No. 1 — No. 2:
Is the measured value within the specified
range?
6 CHECK POWER SUPPLY LINE.
1) Turn ignition switch to ON.
2) Measure voltage between fuel injector and
engine ground on faulty cylinders.
Connector & terminal
#1 (E5) No. 2 (+) — Engine ground ( − − − − ):
#2 (E16) No. 2 (+) — Engine ground ( − − − − ):
#3 (E6) No. 2 (+) — Engine ground ( − − − − ):
#4 (E17) No. 2 (+) — Engine ground ( − − − − ):
Does the measured value exceed the spec-
ified value?
7 CHECK HARNESS BETWEEN FUEL INJEC-
TOR AND ECM CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from fuel injector on
faulty cylinder.
3) Turn ignition switch to ON.
4) Measure voltage between ECM connector
and chassis ground on faulty cylinders.
Connector & terminal
#1 (B134) No. 34 (+) — Chassis ground
( − − − − ):
#2 (B134) No. 23 (+) — Chassis ground
( − − − − ):
#3 (B134) No. 22 (+) — Chassis ground
( − − − − ):
#4 (B134) No. 8 (+) — Chassis ground
( − − − − ):
Does the measured value exceed the spec-
ified value?
8 CHECK FUEL INJECTOR.
1) Turn ignition switch to OFF.
2) Measure resistance between fuel injector
terminals on faulty cylinder.
Terminals
No. 1 — No. 2:
Is the measured value less than the speci-
fied value?
9 CHECK INSTALLATION OF CAMSHAFT PO-
SITION SENSOR/CRANKSHAFT POSITION
SENSOR.
Is camshaft position sensor or crankshaft posi-
tion sensor loosely installed?
Step
EN(H4SO)-170
Value
5 - 20 Ω
10 V
10 V
1 Ω
Loosely installed.
Yes
Go to step 6. Replace faulty fuel
injector. <Ref. to
FU(H4SO)-36,
Fuel Injector.>
Repair poor con- Repair harness
tact in all connec- and connector.
tors in fuel injector
NOTE:
circuit.
In this case, repair
the following:
• Open circuit in
harness between
main relay and fuel
injector connector
on faulty cylinders
• Poor contact in
coupling connector
• Poor contact in
main relay con-
nector
• Poor contact in
fuel injector con-
nector on faulty
cylinders
Repair battery Go to step 8.
short circuit in har-
ness between
ECM and fuel
injector. After
repair, replace
ECM. <Ref. to
FU(H4SO)-45,
Engine Control
Module.>
Replace faulty fuel Go to step 9.
injector <Ref. to
FU(H4SO)-36,
Fuel Injector.> and
replacce ECM
<Ref. to
FU(H4SO)-45,
Engine Control
Module.>
Tighten camshaft Go to step 10.
position sensor or
crankshaft posi-
tion sensor.
No