Chassis SUBARU LEGACY 1997 Service Owners Manual

B2M0560A
10AJ1CHECK HARNESS BETWEEN KNOCK
SENSOR AND ECM CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from ECM.
3) Measure resistance between ECM harness connector
and chassis ground.
: Connector & terminal
(B84) No. 3—Chassis ground:
Is the resistance more than 700 kΩ?
: Go to step10AJ2.
: Go to next.
B2M0560A
: Connector & terminal
(B84) No. 3—Chassis ground:
Is the resistance less than 400 kΩ?
: Go to step10AJ3.
: Go to step10AJ4.
B2M1090
10AJ2
CHECK KNOCK SENSOR.
1) Disconnect connector from knock sensor.
2) Measure resistance between knock sensor connector
terminal and engine ground.
: Terminal
No. 2—Engine ground:
Is the resistance more than 700 kΩ?
: Go to next.
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between knock sensor and ECM
connector

Poor contact in knock sensor connector

Poor contact in coupling connector (B21)
: Is the knock sensor installation bolt tight-
ened securely?
: Replace knock sensor.
: Tighten knock sensor installation bolt securely.
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B2M1090
10AJ3
CHECK KNOCK SENSOR.
1) Disconnect connector from knock sensor.
2) Measure resistance between knock sensor connector
terminal and engine ground.
: Terminal
No. 2—Engine ground:
Is the resistance less than 400 kΩ?
: Replace knock sensor.
: Repair ground short circuit in harness between
knock sensor connector and ECM connector.
NOTE:
The harness between both connectors is shielded. Repair
short circuit of harness together with shield.
B2M0561A
10AJ4
CHECK INPUT SIGNAL FOR ECM.
1) Connect connectors to ECM and knock sensor.
2) Turn ignition switch to ON.
3) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 3 (+)—Chassis ground ():
Is the voltage more than 2 V?
: Even if MIL lights up, the circuit has returned to a
normal condition at this time. (However, the pos-
sibility of poor contact still remains.)
NOTE:
In this case, repair the following:

Poor contact in knock sensor connector

Poor contact in ECM connector

Poor contact in coupling connector (B21)
: Repair poor contact in ECM connector.
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10AP1
CHECK ENGINE/TRANSMISSION TYPE.
: Is engine/transmission type 2200 cc/MT?
: Check AT/MT identification circuit. [T10DD0].>
: Go to step10AP2.
B2M0566A
10AP2
CHECK OUTPUT SIGNAL FROM ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 71 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Go to next.
: Go to step10AP3.
: Is there poor contact in ECM connector?
: Repair poor contact in ECM connector.
: Even if MIL lights up, the circuit has returned to a
normal condition at this time. (However, the pos-
sibility of poor contact still remains.)
NOTE:
In this case, repair the following:

Poor contact in EGR solenoid valve connector

Poor contact in ECM connector

Poor contact in coupling connector (B21)
OBD0678A
10AP3CHECK HARNESS BETWEEN EGR
SOLENOID VALVE AND ECM CONNEC-
TOR.
1) Turn ignition switch to OFF.
2) Disconnect connectors from EGR solenoid valve and
ECM.
3) Measure resistance of harness between EGR solenoid
valve connector and engine ground.
: Connector & terminal
(E18) No. 2—Engine ground:
Is the resistance less than 10Ω?
: Repair ground short circuit in harness between
ECM and EGR solenoid valve connector.
: Go to next step 4).
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B2M0570A
10AT1
CHECK OUTPUT SIGNAL FROM ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 72 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Even if MIL lights up, the circuit has returned to a
normal condition at this time. Contact with SOA
service.
NOTE:
Inspection by DTM is required, because probable cause is
deterioration of multiple parts.
: Go to step10AT2.
OBD0680A
10AT2CHECK HARNESS BETWEEN PURGE
CONTROL SOLENOID VALVE AND ECM
CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connectors from purge control solenoid
valve and ECM.
3) Measure resistance of harness between purge control
solenoid valve connector and engine ground.
: Connector & terminal
(E4) No. 2—Engine ground:
Is the resistance less than 10Ω?
: Repair ground short circuit in harness between
ECM and purge control solenoid valve connector.
: Go to next step 4).
B2M0571A
4) Measure resistance of harness between ECM and
purge control solenoid valve of harness connector.
: Connector & terminal
(B84) No. 72—(E4) No. 2:
Is the resistance less than 1Ω?
: Go to step10AT3.
: Repair open circuit in harness between ECM and
purge control solenoid valve connector.
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H2M1370B
10AU1
CHECK OUTPUT SIGNAL FROM ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 35 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Go to next.
: Go to stepAU2.
: Is there poor contact in ECM connector?
: Repair poor contact in ECM connector.
: Even if MIL lights up, the circuit has returned to a
normal condition at this time. (However, the pos-
sibility of poor contact still remains.)
NOTE:
In this case, repair the following:

Poor contact in vent control solenoid valve connector

Poor contact in ECM connector

Poor contact in coupling connectors (B97, B98 and R57)
H2M1239C
10AU2CHECK HARNESS BETWEEN VENT
CONTROL SOLENOID VALVE AND ECM
CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connectors from vent control solenoid valve
and ECM.
3) Measure resistance of harness between vent control
solenoid valve connector and chassis ground.
: Connector & terminal
(R69) No. 2—Chassis ground:
Is the resistance less than 10Ω?
: Repair ground short circuit in harness between
ECM and vent control solenoid valve connector.
: Go to next step 4).
H2M1371B
4) Measure resistance of harness between ECM and vent
control solenoid valve connector.
: Connector & terminal
(B84) No. 35—(R69) No. 2:
Is the voltage less than 1Ω?
: Go to step10AU3.
: Repair harness and connector.
NOTE:
In this case, repair the following:
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Open circuit in harness between ECM and vent control
solenoid valve connector

Poor contact in coupling connectors (B98 and R57)
H2M1238A
10AU3CHECK VENT CONTROL SOLENOID
VA LV E .
Measure resistance between vent control solenoid valve
terminals.
: Terminals
No. 1—No. 2:
Is the resistance between 10 and 100Ω?
: Go to step10AU4.
: Replace vent control solenoid valve.
H2M1241C
10AU4CHECK POWER SUPPLY TO VENT CON-
TROL SOLENOID VALVE.
1) Turn ignition switch to ON.
2) Measure voltage between vent control solenoid valve
and chassis ground.
: Connector & terminal
(R69) No. 1 (+)—Chassis ground ():
Is the voltage more than 10 V?
: Go to next.
: Repair harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between main relay and vent
control solenoid valve

Poor contact in coupling connectors (B97 and R57)

Poor contact in main relay connector
: Is there poor contact in vent control sole-
noid valve connector?
: Repair poor contact in vent control solenoid valve
connector.
: Contact with SOA service.
NOTE:
Inspection by DTM is required, because probable cause is
deterioration of multiple parts.
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OBD0145A
10AW1CONNECT 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 less than2.8 kPa in function
mode F43?
: Go to step10AW2.
: 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
10AW2CHECK 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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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 step10AW3.
: 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 step10AW3.
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B2M0927
10AW3CHECK HARNESS BETWEEN ECM AND
FUEL TANK PRESSURE SENSOR CON-
NECTOR.
1) Turn ignition switch to OFF.
2) Detach right side trunk side trim panel (Sedan) or right
side rear quarter trim panel (Wagon).
3) Remove right side rear quarter trim pocket (Wagon
model only).
4) Detach right side rear quarter insulator (Wagon model
only).
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)
8) Turn ignition switch to OFF.
9) Disconnect connector from ECM.
10) Measure resistance of harness between ECM and
pressure sensor connector.
H2M1376B
: Connector & terminal
(B84) No. 20—(R47) No. 1:
Is the resistance less than 1Ω?
: Go to next step 11).
: 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 (B98)
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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.
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