1997 SUBARU LEGACY fuel

H2M1257B
11) Measure resistance of harness between fuel tank
pressure sensor connector and chassis ground.
: Connector & terminal
(R47) No. 1—Chassis ground:
Is the resistance more than 500 kΩ?
: Go to next.
: Repair ground short circuit in harness between
ECM and fuel tank pressure sensor connector.
: Is there poor contact in fuel tank pressure
sensor connector?
: Repair poor contact in fuel tank pressure sensor
connector.
: Replace fuel tank pressure sensor.
478
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostic Chart with Trouble Code for RHD Vehicles

B2M1016A
11AX1CONNECT SUBARU SELECT MONITOR
OR THE OBD-II GENERAL SCAN TOOL,
AND READ DATA.
1) Turn ignition switch to OFF.
2) Remove fuel filler cap.
3) Install fuel filler cap.
4) Connect Subaru Select Monitor or the OBD-II general
scan tool to data link connector.
5) Turn ignition switch to ON and Subaru Select Monitor or
the OBD-II general scan tool switch to ON.
H2M1326
6) Read the data on Subaru Select Monitor or the OBD-II
general scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F43

F43: Display shows pressure signal value sent from fuel
tank pressure sensor.
: Is the value more than 2.8 kPa in function
mode F43?
: Go to step11AX4.
: Go to step11AX2.

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
B2M0535A
11AX2CHECK INPUT SIGNAL FOR ECM.
(USING VOLTAGE METER AND SUBARU
SELECT MONITOR.)
1) Measure voltage between ECM connector and chassis
ground.
: Connector & terminal
(B84) No. 21 (+)—Chassis ground ():
Is the voltage more than 4.5 V?
: Go to next step 2).
: Go to next.
480
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostic Chart with Trouble Code for RHD Vehicles

B2M0535A
: Does the voltage change more than 4.5 V by
shaking harness and connector of ECM
while monitoring the value with voltage
meter?
: Repair poor contact in ECM connector.
: Contact with SOA service.
NOTE:
Inspection by DTM is required, because probable cause is
deterioration of multiple parts.
H2M1374B
2) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 4 (+)—Chassis ground ():
Is the voltage less than 0.2 V?
: Go to step11AX3.
: Go to next step 3).
H2M1326
3) Read data on Subaru Select Monitor.

Subaru Select Monitor
Designate mode using function key.
Function mode: F43

F43: Display shows pressure signal value sent from fuel
tank pressure sensor.
: Does the value change more than2.8 kPa
by shaking harness and connector of ECM
while monitoring the value with Subaru
select monitor?
: Repair poor contact in ECM connector.
: Go to step11AX3.
481
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostic Chart with Trouble Code for RHD Vehicles

B2M0927
11AX3CHECK HARNESS BETWEEN ECM AND
FUEL TANK PRESSURE SENSOR CON-
NECTOR.
1) Turn ignition switch to OFF.
2) Detach right side rear quarter trim panel.
3) Remove right side rear quarter trim pocket.
4) Detach right side rear quarter insulator.
H2M1255B
5) Disconnect connector from fuel tank pressure sensor.
6) Turn ignition switch to ON.
7) Measure voltage between fuel tank pressure sensor
connector and chassis ground.
: Connector & terminal
(R47) No. 3 (+)—Chassis ground ():
Is the voltage more than 4.5 V?
: Go to next step 8).
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between ECM and fuel tank
pressure sensor connector

Poor contact in coupling connector (B97)
H2M1375B
8) Turn ignition switch to OFF.
9) Disconnect connector from ECM.
10) Measure resistance of harness between ECM and
pressure sensor connector.
: Connector & terminal
(B84) No. 4—(R47) No. 2:
Is the resistance less than 1Ω?
: Go to next.
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between ECM and fuel tank
pressure sensor connector

Poor contact in coupling connector (B97)
482
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostic Chart with Trouble Code for RHD Vehicles

H2M1376B
: Connector & terminal
(B84) No. 20—(R47) No. 1:
Is the resistance less than 1Ω?
: Go to next.
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between ECM and fuel tank
pressure sensor connector

Poor contact in coupling connector (B97)
: Is there poor contact in fuel tank pressure
sensor connector?
: Repair poor contact in fuel tank pressure sensor
connector.
: Replace fuel tank pressure sensor.
B2M0927
11AX4CHECK HARNESS BETWEEN ECM AND
FUEL TANK PRESSURE SENSOR CON-
NECTOR.
1) Turn ignition switch to OFF and Subaru Select Monitor
or the OBD-II general scan tool switch to OFF.
2) Detach right side rear quarter trim panel.
3) Remove right side rear quarter trim pocket.
4) Detach right side rear quarter insulator.
H2M1326
5) Disconnect connector from fuel tank pressure sensor.
6) Remove fuel filler cap.
7) Install fuel filler cap.
8) Turn ignition switch to ON and Subaru Select Monitor or
the OBD-II general scan tool switch to ON.
9) Read data on Subaru select monitor or the OBD-II gen-
eral scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F43
: Is the value more than 2.8 kPa in function
mode F43?
: Repair battery short circuit in harness between
ECM and fuel tank pressure sensor connector.
: Replace fuel tank pressure sensor.

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
483
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostic Chart with Trouble Code for RHD Vehicles

B2M1101
AY: DTC P0461
—FUEL LEVEL SENSOR CIRCUIT RANGE/
PERFORMANCE PROBLEM—
DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
WIRING DIAGRAM:
B2M1021
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

484
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostic Chart with Trouble Code for RHD Vehicles

11 AY 1CHECK 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“11. Diagnos-
tics Chart with Trouble Code”. [T11TA0].>
NOTE:
In this case, it is not necessary to inspect this trouble.
: Replace fuel sending unit and fuel sub meter unit.
485
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostic Chart with Trouble Code for RHD Vehicles

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

Two consecutive driving cycles with fault
WIRING DIAGRAM:
B2M1021
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

486
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostic Chart with Trouble Code for RHD Vehicles