1997 SUBARU LEGACY fuel

10AY1CHECK DTC P0462 OR P0463 ON DIS-
PLAY.
: Does the Subaru select monitor or OBD-II
general scan tool indicate DTC P0462 or
P0463?
: Inspect DTC P0462 or P0463 using“10. Diagnos-
tics Chart with Trouble Code”. [T10A0].>
NOTE:
In this case, it is not necessary to inspect this trouble.
: Replace fuel sending unit and fuel sub meter unit.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M1102
AZ: DTC P0462
—FUEL LEVEL SENSOR CIRCUIT LOW
INPUT—
DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
WIRING DIAGRAM:
B2M0933
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

269
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
10. Diagnostic Chart with Trouble Code for LHD Vehicles

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.
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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

B2M0945A
4) Measure resistance of harness between combination
meter connector and chassis ground.
: Connector & terminal
(i10) No. 3—Chassis ground:
Is the resistance less than 200Ω?
: Go to step10AZ6.
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between combination meter con-
nector and junction A on rear wiring harness

Poor contact in coupling connectors (i3 and B99)
10AZ6
CHECK COMBINATION METER.
1) Disconnect speedometer cable from combination meter
and remove combination meter.
: Is the fuel meter installation screw tightened
securely?
: Go to next step 2).
: Tighten fuel meter installation screw securely.
2) Remove printed circuit plate assembly from combina-
tion meter assembly.
: Is there flaw or burning on printed circuit
plate assembly?
: Replace printed circuit plate assembly.
: Replace fuel meter assembly.
274
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M1103
BA: DTC P0463
—FUEL LEVEL SENSOR CIRCUIT HIGH
INPUT—
DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
WIRING DIAGRAM:
B2M0933
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

275
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