Subaru Legacy 2004 Service Manual page 1410

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step
1 CHECK POWER SUPPLY LINE.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from fuel injector.
3) Turn the ignition switch to ON.
4) Measure the 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 (
2 CHECK FUEL INJECTOR.
1) Turn the ignition switch to OFF.
2) Measure the resistance between fuel injec-
tor terminals on faulty cylinder.
Terminals
No. 1 — No. 2:
3 CHECK OUTPUT SIGNAL FROM ECM.
1) Connect the connector to the fuel injector.
2) Turn the ignition switch to ON.
3) Measure the voltage between ECM con-
nector and chassis ground on faulty cylinders.
Connector & terminal
#1 (B136) No. 6 (+) — Chassis ground (
#2 (B136) No. 5 (+) — Chassis ground (
#3 (B136) No. 4 (+) — Chassis ground (
#4 (B136) No. 3 (+) — Chassis ground (
4 CHECK GROUND CIRCUIT FOR ECM.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Measure the resistance between ECM con-
nector and chassis ground.
Connector & terminal
(B137) No. 7 — Chassis ground:
Check
Is the voltage more than 10 V? Go to step 2.
"
):
"
):
"
):
"
):
Is the resistance less than 11
— 12 '?
Is the voltage more than 10 V? Go to step 4.
"
):
"
):
"
):
"
):
Is the resistance less than 5
'?
EN(H4DOTC)(diag)-121
ENGINE (DIAGNOSTICS)
Yes
Repair the har-
ness and connec-
tor.
NOTE:
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 connec-
tor
• Poor contact in
fuel injector con-
nector on faulty
cylinders
Go to step 3. Replace the faulty
fuel injector and
ECM. <Ref. to
FU(H4DOTC)-30,
Fuel Injector.>
Repair the har-
ness and connec-
tor.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
ECM and fuel
injector connector
• Poor contact in
coupling connector
Repair the poor Repair ground
contact in fuel open circuit in
injector and ECM ECM.
connector.
No