Subaru 2009 IMPREZA, Service Manual

Page: 1301 / 3619

EN(H4DOTC)(diag)-80
Diagnostics for Engine Starting Failure
ENGINE (DIAGNOSTICS)
Step Check Yes No
1 CHECK OPERATION OF EACH FUEL INJEC-
TOR.
While cranking the engine, check each fuel
injector emits operating sound. Use a sound
scope or attach a screwdriver to the injector for
this check.
Does the fuel injector emit
operating sound? Check the fuel
pressure. <Ref. to
ME(H4DOTC)-25,
INSPECTION,
Fuel Pressure.> Go to step 2 .
2 CHECK POWER SUPPLY TO EACH FUEL IN-
JECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from fuel injector.
3) Turn the ignition switch to ON.
4) Measure the power supply voltage between
fuel injector connector and the engine ground.
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 (–):
Is the voltage 10 V or more? Go to step 3 . Repair the harness
and connector.
NOTE:
In this case, repair
the following item:
• Open circuit in
harness between
main relay connec-
tor and fuel injector
connector
• Poor contact of
main relay connec-
tor
• Poor contact of
coupling connector
3 CHECK HARNESS BETWEEN ECM AND
FUEL INJECTOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM.
3) Measure the resistance of harness between
ECM and fuel injector connector.
Connector & terminal
(B137) No. 8 — (E5) No. 1:
(B137) No. 9 — (E16) No. 1:
(B137) No. 10 — (E6) No. 1:
(B137) No. 11 — (E17) No. 1:
Is the resistance less than 1
:
? Go to step 4 . Repair the harness
and connector.
NOTE:
In this case, repair
the following item:
• Open circuit in
harness between
ECM and fuel in-
jector connector
• Poor contact of
coupling connector
4 CHECK HARNESS BETWEEN ECM AND
FUEL INJECTOR CONNECTOR.
Measure the resistance of harness between
ECM and chassis ground.
Connector & terminal
(B137) No. 8 — Chassis ground:
(B137) No. 9 — Chassis ground:
(B137) No. 10 — Chassis ground:
(B137) No. 11 — Chassis ground:
Is the resistance 1 M
:
or
more?
Go to step 5 . Repair the short
circuit to ground in
harness between
ECM and fuel
injector connector.
5 CHECK EACH FUEL INJECTOR.
Measure the resistance between each fuel
injector terminals.
Terminals
No. 1 — No. 2:
Is the resistance 5 — 20
:
? Go to step 6 . Replace the faulty
fuel injector. <Ref.
to FU(H4DOTC)-
41, Fuel Injector.>
6 CHECK POOR CONTACT.
Check for poor contact of ECM connector.
Is there poor contact of ECM
connector? Repair the poor
contact of ECM
connector. Inspection using
“General Diagnostic
Table”. <Ref. to
EN(H4DOTC)(diag)
-367, INSPEC-
TION, General
Diagnostic Table.>