1997 SUBARU LEGACY fuel pump

OBD0145A
10V1CONNECT SUBARU SELECT MONITOR
OR THE OBD-II GENERAL SCAN TOOL,
AND READ DATA.
1) Turn ignition switch to OFF.
2) Connect Subaru Select Monitor or the OBD-II general
scan tool to data link connector.
3) Turn ignition switch to ON and Subaru Select Monitor or
OBD-II general scan tool switch to ON.
4) Start engine.
H2M1308
5) Read data on Subaru Select Monitor or OBD-II general
scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F44

F44: Fuel temperature is indicated in“°C”and“°F”.
: Is the value greater than 150°Cor300°Fin
function mode F44?
: Go to step10V2.
: Even if MIL lights up, the circuit has returned to a
normal condition at this time.

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
G2M0340
10V2CHECK HARNESS BETWEEN FUEL TEM-
PERATURE SENSOR AND ECM CON-
NECTOR.
1) Turn ignition switch to OFF.
2) Remove access hole lid.
3) Disconnect connector from fuel pump.
OBD0145A
4) Connect Subaru Select Monitor or the OBD-II general
scan tool to data link connector.
5) Turn ignition switch and Subaru Select Monitor or
OBD-II general scan tool switch to ON.
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H2M1308
6) Read data on Subaru Select Monitor or the OBD-II gen-
eral scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F44

F44: Fuel temperature is indicated in“°C”and“°F”.
: Is the value less than40°Cor40°Fin
function mode F44?
: Replace fuel temperature sensor.
: Repair ground short circuit in harness between fuel
pump and ECM connector.

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
199
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0145A
10W1CONNECT SUBARU SELECT MONITOR
OR THE OBD-II GENERAL SCAN TOOL,
AND READ DATA.
1) Turn ignition switch to OFF.
2) Connect Subaru Select Monitor or the OBD-II general
scan tool to data link connector.
3) Turn ignition switch to ON and Subaru Select Monitor or
OBD-II general scan tool switch to ON.
4) Start engine.
H2M1308
5) Read data on Subaru Select Monitor or OBD-II general
scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F44

F44: Fuel temperature is indicated in“°C”and“°F”.
: Is the value less than40°Cor40°Fin
function mode F44?
: Go to step10W2.
: Repair poor contact.
NOTE:
In this case, repair the following:

Poor contact in fuel pump connector

Poor contact in ECM connector

Poor contact in coupling connector (B22, B98 and R57)

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
G2M0340
10W2CHECK HARNESS BETWEEN FUEL TEM-
PERATURE SENSOR AND ECM CON-
NECTOR.
1) Turn ignition switch to OFF.
2) Remove access hole lid.
3) Disconnect connector from fuel pump.
B2M0917A
4) Measure voltage between fuel pump connector and
chassis ground.
: Connector & terminal
(R58) No. 6 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Repair battery short circuit in harness between
ECM and fuel pump connector.
: Go to next step 5).
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M0917A
5) Turn ignition switch to ON.
6) Measure voltage between fuel pump connector and
chassis ground.
: Connector & terminal
(R58) No. 6 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Repair battery short circuit in harness between
ECM and fuel pump connector.
: Go to step10W3.
B2M0917A
10W3CHECK HARNESS BETWEEN FUEL TEM-
PERATURE SENSOR AND ECM CON-
NECTOR.
1) Measure voltage between fuel pump connector and
chassis ground.
: Connector & terminal
(R58) No. 6 (+)—Chassis ground ():
Is the voltage more than 4 V?
: Go to next step 2).
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between ECM and fuel pump
connector

Poor contact in fuel pump connector

Poor contact in ECM connector

Poor contact in coupling connectors (B98 and R57)
B2M0918A
2) Turn ignition switch to OFF.
3) Measure resistance of harness between fuel pump con-
nector and chassis ground.
: Connector & terminal
(R58) No. 5—Chassis ground:
Is the resistance less than 5Ω?
: Replace fuel temperature sensor.
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between ECM and fuel pump
connector

Poor contact in fuel pump connector

Poor contact in ECM connector

Poor contact in coupling connectors (B22, B98 and R57)
202
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

H2M1414B
10AZ3CHECK INPUT SIGNAL FOR ECM.
(USING VOLTAGE METER AND SUBARU
SELECT MONITOR.)
1) Turn ignition switch to ON. (Engine OFF)
2) Measure voltage between ECM connector and chassis
ground.
: Connector & terminal
(B84) No. 27 (+)—Chassis ground ():
Is the voltage less than 0.12 V?
: Go to step10AZ4.
: Go to next.
H2M1327
: Does the value change less than 0.12 V by
shaking harness and connector of ECM
while monitoring the value with Subaru
Select Monitor?

Subaru Select Monitor
Designate mode using function key.
Function mode: F45

F45: Fuel level sensor output signal is indicated.
: Repair poor contact in ECM connector.
: Even if MIL lights up, the circuit has returned to a
normal condition at this time. A temporary poor
contact of the connector may be the cause.
NOTE:
In this case, repair the following:

Poor contact in fuel pump connector

Poor contact in combination meter connector

Poor contact in ECM connector

Poor contact in coupling connector (i3, B99, B22, B98
and R57)
G2M0340
10AZ4CHECK HARNESS BETWEEN ECM, COM-
BINATION METER AND FUEL PUMP
CONNECTOR.
1) Turn ignition switch to OFF.
2) Remove fuel pump access hole lid located on the right
rear of trunk compartment floor (Sedan) or luggage com-
partment floor (Wagon).
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
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B2M0940A
3) Disconnect connector from fuel pump.
4) Measure resistance of harness between fuel pump con-
nector and chassis ground.
: Connector & terminal
(R58) No. 3—Chassis ground:
Is the resistance less than 10Ω?
: Go to next step 5).
: Go to step10AZ5.
G2M0863
5) Remove service hole cover located on the left rear of
trunk compartment floor (Sedan) or luggage compartment
floor (Wagon).
B2M0940A
6) Disconnect connector from fuel sub meter unit.
7) Measure resistance of harness between fuel pump con-
nector and chassis ground.
: Connector & terminal
(R58) No. 3—Chassis ground:
Is the resistance less than 10Ω?
: Repair ground short circuit in harness between
fuel pump and fuel sub meter unit connector.
: Go to next step 8).
B2M0941A
8) Separate fuel tank cord connector (R57) and rear wir-
ing harness connector (R15).
9) Measure resistance of harness between fuel sub meter
unit connector and chassis ground.
: Connector & terminal
(R59) No. 1—Chassis ground:
Is the resistance less than 10Ω?
: Repair ground short circuit in fuel tank cord.
: Go to next step 10).
B2M0942A
10) Separate rear wiring harness connector (R2) and bulk-
head wiring harness connector (B98).
11) Measure resistance of harness between rear wiring
harness connector and chassis ground.
: Connector & terminal
(R15) No. 3—Chassis ground:
Is the resistance less than 10Ω?
: Go to next step 12).
: Repair ground short circuit in bulkhead wiring har-
ness.
272
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M0943A
12) Separate rear wiring harness connector (R3) and bulk-
head wiring harness connector (B99).
13) Measure resistance of harness between rear wiring
harness connector and chassis ground.
: Connector & terminal
(R3) No. 20—Chassis ground:
Is the resistance less than 10Ω?
: Repair ground short circuit in rear wiring harness.
: Go to next step 14).
B2M0944A
14) Separate bulkhead wiring harness connector (B38)
and instrument panel wiring harness connector (i3).
15) Measure resistance of harness between bulkhead wir-
ing harness connector and chassis ground.
: Connector & terminal
(B99) No. 20—Chassis ground:
Is the resistance less than 10Ω?
: Repair ground short circuit in bulkhead wiring har-
ness.
: Repair ground short circuit in instrument panel
wiring harness.
B6M0121
10AZ5CHECK HARNESS BETWEEN COMBINA-
TION METER AND FUEL PUMP CONNEC-
TOR.
1) Connect connector to fuel pump.
2) Pull out combination meter from instrument panel. to 6-2 [W13A1].>
3) Disconnect connector from combination meter.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

H2M1414B
10BA3CHECK INPUT SIGNAL FOR ECM.
(USING VOLTAGE METER AND SUBARU
SELECT MONITOR.)
1) Turn ignition switch to ON. (Engine OFF)
2) Measure voltage between ECM connector and chassis
ground.
: Connector & terminal
(B84) No. 27 (+)—Chassis ground ():
Is the voltage more than 4.75 V?
: Go to step10BA4.
: Even if MIL lights up, the circuit has returned to a
normal condition at this time. A temporary poor
contact of the connector may be the cause.
NOTE:
In this case, repair the following:

Poor contact in fuel pump connector

Poor contact in combination meter connector

Poor contact in ECM connector

Poor contact in coupling connector (i3, B99, B22, B98
and R57)
G2M0340
10BA4
CHECK FUEL LEVEL SENSOR.
1) Turn ignition switch to OFF.
2) Remove fuel pump access hole lid located on the right
rear of trunk compartment floor (Sedan) or luggage com-
partment floor (Wagon).
B2M0935
3) Disconnect connector from fuel pump.
4) Measure resistance between connector terminals of
fuel pump.
: Terminals
No. 3—No. 5:
Is the resistance less than 100Ω?
: Go to step10BA5.
: Replace fuel sending unit.
G2M0863
10BA5
CHECK FUEL SUB LEVEL SENSOR.
1) Remove service hole cover located on the left rear of
trunk compartment floor (Sedan) or luggage compartment
floor (Wagon).
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles