1997 SUBARU LEGACY ignition

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.
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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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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.
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10. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0145A
10H1CONNECT 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.
B2M0479
5) Read data on Subaru Select Monitor or OBD-II general
scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F04

F04: Water temperature is indicated in“°C”and“°F”.
: Is the value greater than 150°Cor300°Fin
function mode F04?
: Go to step10H2.
: Repair poor contact.
NOTE:
In this case, repair the following:

Poor contact in engine coolant temperature sensor

Poor contact in ECM

Poor contact in coupling connector (B21)

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
OBD0618A
10H2CHECK HARNESS BETWEEN ENGINE
COOLANT TEMPERATURE SENSOR AND
ECM CONNECTOR.
1) Turn ignition switch to OFF.
2) Remove idle air control solenoid valve by-pass air hose.
3) Disconnect connector from engine coolant temperature
sensor.
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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10. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0145A
10I1CONNECT 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.
B2M0479
5) Read data on Subaru Select Monitor or OBD-II general
scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F04

F04: Water temperature is indicated in“°C”and“°F”.
: Is the value less than40°Cor40°Fin
function mode F04?
: Go to step10I3.
: Repair poor contact.
NOTE:
In this case, repair the following:

Poor contact in engine coolant temperature sensor

Poor contact in ECM

Poor contact in coupling connector (B21)

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
OBD0618A
10I2CHECK HARNESS BETWEEN ENGINE
COOLANT TEMPERATURE SENSOR AND
ECM CONNECTOR.
1) Turn ignition switch to OFF.
2) Remove idle air control solenoid valve by-pass air hose.
3) Disconnect connector from engine coolant temperature
sensor.
OBD0696A
4) Measure voltage between engine coolant temperature
sensor connector and engine ground.
: Connector & terminal
(E8) No. 1 (+)—Engine ground ():
Is the voltage more than 10 V?
: Repair battery short circuit in harness between
ECM and engine coolant temperature sensor con-
nector.
: Go to next step 5).
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10. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0696A
5) Turn ignition switch to ON.
6) Measure voltage between engine coolant temperature
sensor connector and engine ground.
: Connector & terminal
(E8) No. 1 (+)—Engine ground ():
Is the voltage more than 10 V?
: Repair battery short circuit in harness between
ECM and engine coolant temperature sensor con-
nector.
: Go to step10I3.
OBD0696A
10I3CHECK HARNESS BETWEEN ENGINE
COOLANT TEMPERATURE SENSOR AND
ECM CONNECTOR.
1) Measure voltage between engine coolant temperature
sensor connector and engine ground.
: Connector & terminal
(E8) No. 1 (+)—Engine 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 engine cool-
ant temperature sensor connector

Poor contact in engine coolant temperature sensor con-
nector

Poor contact in ECM connector

Poor contact in coupling connector (B21)
OBD0697A
2) Turn ignition switch to OFF.
3) Measure resistance of harness between engine coolant
temperature sensor connector and engine ground.
: Connector & terminal
(E8) No. 2—Engine ground:
Is the resistance less than 5Ω?
: Replace engine coolant temperature sensor.
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between ECM and engine cool-
ant temperature sensor connector

Poor contact in engine coolant temperature sensor con-
nector

Poor contact in ECM connector

Poor contact in coupling connector (B21)
159
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

OBD0145A
10K1CONNECT 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.
B2M0482
5) Read data on Subaru Select Monitor or OBD-II general
scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F07

F07: Throttle position sensor output signal is indicated.
: Is the value less than 0.1 V in function
mode F07?
: Go to step10G2.
: 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 throttle position sensor connector

Poor contact in ECM connector

Poor contact in coupling connector (B21)

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

OBD0700A
10K3CHECK HARNESS BETWEEN ECM AND
THROTTLE POSITION SENSOR CON-
NECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connectors from throttle position sensor.
3) Turn ignition switch to ON.
4) Measure voltage between throttle position sensor con-
nector and engine ground.
: Connector & terminal
(E13) No. 3 (+)—Engine ground ():
Is the voltage more than 4.5 V?
: Go to next step 5).
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between throttle position sensor
and ECM connector

Poor contact in throttle position sensor connector

Poor contact in ECM connector

Poor contact in coupling connector (B21)
B2M0543A
5) Turn ignition switch to OFF.
6) Measure resistance of harness between ECM connec-
tor and throttle position sensor connector.
: Connector & terminal
(B84) No. 6—(E13) No. 2:
Is the resistance less than 1Ω?
: Go to next step 7).
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between throttle position sensor
and ECM connector

Poor contact in ECM connector

Poor contact in throttle position sensor connector

Poor contact in coupling connector (B21)
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles