1997 SUBARU LEGACY sensor

OBD0145A
10F1CONNECT 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
the OBD-II general scan tool switch to ON.
4) Start engine.
B2M0756
5) Read the data on Subaru Select Monitor or the OBD-II
general scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F21

F21: Display shows pressure signal value sent from
pressure sensor.
: Is the value less than 0 kPa in function
mode F21?
: Go to step10F2.
: 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.
B2M0535A
10F2CHECK 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.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD 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.
B2M0536A
2) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 26 (+)—Chassis ground ():
Is the voltage less than 0.2 V?
: Go to step10F3.
: Go to next step 3).
B2M0755
3) Read data on Subaru Select Monitor.

Subaru Select Monitor
Designate mode using function key.
Function mode: F20

F20: Display shows pressure signal value sent from
pressure sensor.
: Does the value change more than 0 kPa by
shaking harness and connector of ECM
while monitoring the value with Subaru
select monitor?
: Repair poor contact in ECM connector.
: Go to step10F3.
OBD0693A
10F3CHECK HARNESS BETWEEN ECM AND
PRESSURE SENSOR CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from pressure sensor.
3) Turn ignition switch to ON.
4) Measure voltage between pressure sensor connector
and engine ground.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

: Connector & terminal
(B2) No. 3 (+)—Engine ground ():
Is the voltage more than 4.5 V?
: Go to next step 5).
: Repair open circuit in harness between ECM and
pressure sensor connector.
B2M1065A
5) Turn ignition switch to OFF.
6) Disconnect connector from ECM.
7) Measure resistance of harness between ECM and pres-
sure sensor connector.
: Connector & terminal
(B84) No. 20—(B2) No. 1:
Is the resistance less than 1Ω?
: Go to next step 8).
: Repair open circuit in harness between ECM and
pressure sensor connector.
OBD0695A
8) Measure resistance of harness between pressure sen-
sor connector and engine ground.
: Connector & terminal
(B2) No. 2—Engine ground:
Is the resistance more than 500 kΩ?
: Go to next.
: Repair ground short circuit in harness between
ECM and pressure sensor connector.
: Is there poor contact in pressure sensor
connector?
: Repair poor contact in pressure sensor connector.
: Replace pressure sensor.
148
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M1066
G: DTC P0108
—PRESSURE SENSOR CIRCUIT HIGH
INPUT—
DTC DETECTING CONDITION:

Immediately at fault recognition
WIRING DIAGRAM:
B2M1308
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0145A
10G1CONNECT 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
the OBD-II general scan tool switch to ON.
4) Start engine.
B2M0756
5) Read the data on Subaru Select Monitor or the OBD-II
general scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F21

F21: Display shows pressure signal value sent from
pressure sensor.
: Is the value more than 140 kPa in function
mode F21?
: Go to step10G4.
: Go to step10G2.

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
B2M0535A
10G2CHECK 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.
150
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD 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.
B2M0536A
2) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 26 (+)—Chassis ground ():
Is the voltage less than 0.2 V?
: Go to step10G3.
: Go to next step 3).
B2M0755
3) Read data on Subaru Select Monitor.

Subaru Select Monitor
Designate mode using function key.
Function mode: F20

F20: Display shows pressure signal value sent from
pressure sensor.
: Does the value change more than 0 kPa by
shaking harness and connector of ECM
while monitoring the value with Subaru
select monitor?
: Repair poor contact in ECM connector.
: Go to step10G3.
151
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0693A
10G3CHECK HARNESS BETWEEN ECM AND
PRESSURE SENSOR CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from pressure sensor.
3) Turn ignition switch to ON.
4) Measure voltage between pressure sensor connector
and engine ground.
: Connector & terminal
(B2) No. 3 (+)—Engine ground ():
Is the voltage more than 4.5 V?
: Go to next step 5).
: Repair open circuit in harness between ECM and
pressure sensor connector.
B2M0537A
5) Turn ignition switch to OFF.
6) Disconnect connector from ECM.
7) Measure resistance of harness between ECM and pres-
sure sensor connector.
: Connector & terminal
(B84) No. 26—(B2) No. 2:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between ECM and
pressure sensor connector.
: Connector & terminal
(B84) No. 20—(B2) No. 1:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between ECM and
pressure sensor connector.
: Is there poor contact in pressure sensor
connector?
: Repair poor contact in pressure sensor connector.
: Replace pressure sensor.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M0756
10G4CHECK HARNESS BETWEEN ECM AND
PRESSURE SENSOR CONNECTOR.
1) Turn ignition switch to OFF and Subaru Select Monitor
or the OBD-II general scan tool switch to OFF.
2) Disconnect connector from pressure sensor.
3) Turn ignition switch to ON and Subaru Select Monitor or
the OBD-II general scan tool switch to ON.
4) Read data on Subaru select monitor or the OBD-II gen-
eral scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F21
: Is the value more than 140 kPa in function
mode F21?
: Repair battery short circuit in harness between
ECM and pressure sensor connector.
: Replace pressure sensor.

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
153
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles