Subaru Legacy 2004 Service Manual page 494

ENGINE (DIAGNOSTICS)
Step
1 CHECK OPERATING SOUND OF FUEL
PUMP.
Check if the fuel pump is in operation for two
seconds 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
2.0)(diag)-39, Compulsory Valve Operation
Check Mode.>
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:
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 (
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. 1:
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:
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. 2 — No. 1:
Diagnostics for Engine Starting Failure
Does the fuel pump produce
operating sound?
Is the resistance less than 5
&?
Is the voltage more than 10 V? Replace the fuel
"
):
Is the resistance less than 1
&?
Is the resistance more than 1
M&?
Is the resistance less than 10
&?
EN(H4SO 2.0)(diag)-62
Check Yes
Check the fuel
injector circuit.
<Ref. to EN(H4SO
2.0)(diag)-64,
FUEL INJECTOR
CIRCUIT, Diag-
nostics for Engine
Starting Failure.>
Go to step 3.
pump. <Ref. to
FU(H4SO 2.0)-47,
Fuel Pump.>
Go to step 5.
Go to step 6.
Go to step 7.
No
Go to step 2.
Repair the har-
ness and connec-
tor.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
fuel pump connec-
tor and chassis
grounding terminal
Go to step 4.
Repair the har-
ness and connec-
tor.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
fuel pump connec-
tor and chassis
grounding terminal
• Poor contact in
coupling connector
Repair the short
circuit in harness
between fuel pump
and fuel pump
relay connector.
Replace the fuel
pump relay. <Ref.
to FU(H4SO 2.0)-
47, Fuel Pump.>