Subaru 2006 Legacy, Manual

Page: 418 / 4302

EN(H4SO)(diag)-66
Diagnostics for Engine Starting Failure
ENGINE (DIAGNOSTICS)
Step Check Yes No
1 CHECK OPERATING SOUND OF FUEL
PUMP.
Check if the fuel pump operates for two sec-
onds when turning the ignition switch to ON.
NOTE:
Fuel pump operation can also be executed us-
ing Subaru Select Monitor.
Refer to “Compulsory Valve Operation Check
Mode” for procedures. <Ref. to EN(H4SO)(di-
ag)-44, Compulsory Valve Operation Check
Mode.>
Does the fuel pump emit oper-
ating sound? Check the fuel
injector circuit.
<Ref. to
EN(H4SO)(diag)-
68, FUEL INJEC-
TOR CIRCUIT,
Diagnostics for
Engine Starting
Failure.> Go to step
2
.
2 CHECK GROUND CIRCUIT OF FUEL PUMP.
1) Turn the ignition switch to OFF.
2) Remove the fuel pump access hole lid.
3) Disconnect the connector from fuel pump.
4) Measure the resistance of harness connec-
tor between fuel pump and chassis ground.
Connector & terminal
(R58) No. 6 — Chassis ground:
Is the resistance less than 5
Ω
?
Go to step 3 . Repair the har-
ness and connec-
tor.
NOTE:
In this case, repair
the following item:
Open circuit in har-
ness between fuel
pump
connector
and chassis
grounding terminal
3 CHECK POWER SUPPLY TO FUEL PUMP.
1) Turn the ignition switch to ON.
2) Measure the voltage of power supply circuit
between fuel pump connector and chassis
ground.
Connector & terminal
(R58) No. 5 (+) — Chassis ground (–):
Is the voltage more than 10 V? Replace the fuel
pump. <Ref. to
FU(H4SO)-50,
Fuel Pump.>
Go to step
4
.
4 CHECK HARNESS BETWEEN FUEL PUMP
AND FUEL PUMP RELAY CONNECTOR.
1) Turn the ignition switch to OFF.
2) Measure the resistance of harness connec-
tor between fuel pump and fuel pump relay.
Connector & terminal
(R58) No. 5 — (B362) No. 2:
Is the resistance less than 1
Ω
?
Go to step
5
. Repair the har-
ness and connec-
tor.
NOTE:
In this case, repair
the following item:
• Open circuit in
harness between
fuel pump connec-
tor and chassis
grounding terminal
• Poor contact of
coupling connector
5 CHECK HARNESS BETWEEN FUEL PUMP
AND FUEL PUMP RELAY CONNECTOR.
Measure the resistance of harness between
fuel pump and fuel pump relay connector.
Connector & terminal
(R58) No. 5 — Chassis ground:
Is the resistance more than 1
M
Ω
?
Go to step 6 . Repair the short
circuit of harness
between fuel pump
and fuel pump
relay connector.
6 CHECK FUEL PUMP RELAY.
1) Disconnect the connectors from fuel pump
relay and main relay.
2) Remove the fuel pump relay and main relay
with bracket.
3) Connect the battery to fuel pump relay con-
nector terminals No. 3 and No. 4.
4) Measure the resistance between connector
terminals of fuel pump relay.
Terminals
No. 1 — No. 2:
Is the resistance less than 10
Ω
?
Go to step
7
. Replace the fuel
pump relay. <Ref.
to FU(H4SO)-50,
Fuel Pump.>
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