Subaru Legacy 2002 Service Manual page 1403

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Engine (DIAGNOSTICS)
No.
2 CHECK OUTPUT SIGNAL FROM ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM connector
and chassis ground on faulty cylinders.
Connector & terminal
#1 (B137) No. 1 (+) — Chassis ground
(−):
#2 (B136) No. 6 (+) — Chassis ground
(−):
#3 (B136) No. 5 (+) — Chassis ground
(−):
#4 (B136) No. 4 (+) — Chassis ground
(−):
#5 (B136) No. 3 (+) — Chassis ground
(−):
#6 (B136) No. 1 (+) — Chassis ground
(−):
3 CHECK HARNESS BETWEEN FUEL INJEC-
TOR AND ECM CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from fuel injector on
faulty cylinders.
3) Measure voltage between ECM connector
and engine ground on faulty cylinders.
Connector & terminal
#1 (E5) No. 1 — Engine ground:
#2 (E16) No. 1 — Engine ground:
#3 (E6) No. 1 — Engine ground:
#4 (E17) No. 1 — Engine ground:
#5 (E43) No. 1 — Engine ground:
#6 (E44) No. 1 — Engine ground:
4 CHECK HARNESS BETWEEN FUEL INJEC-
TOR AND ECM CONNECTOR.
Measure resistance of harness connector
between ECM connector and fuel injector on
faulty cylinders.
Connector & terminal
#1 (B137) No. 1 — (E5) No. 1:
#2 (B136) No. 6 — (E16) No. 1:
#3 (B136) No. 5 — (E6) No. 1:
#4 (B136) No. 4 — (E17) No. 1:
#5 (B136) No. 3 — (E43) No. 1:
#6 (B136) No. 1 — (E44) No. 1:
5 CHECK FUEL INJECTOR.
Measure resistance between fuel injector ter-
minals on faulty cylinder.
Terminals
No. 1 — No. 2:
Step
Is the voltage more than 10
V?
Is the resistance less than
10 Ω?
Is the resistance less than
1 Ω?
Is the resistance between 5
and 20 Ω?
EN(H6)-196
Check Yes
Go to step 7.
Repair ground
short circuit in
harness between
fuel injector and
ECM connector.
Go to step 5.
Go to step 6.
No
Go to step 3.
Go to step 4.
Repair harness
and connector.
NOTE:
In this case,
repair the follow-
ing:
¼ Open circuit in
harness between
ECM and fuel
injector connector
¼ Poor contact in
coupling connec-
tor
Replace faulty
fuel injector. <Ref.
to FU(H6)-39,
Fuel Injector.>