1997 SUBARU LEGACY service

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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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.
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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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.
272
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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10. Diagnostic Chart with Trouble Code for LHD Vehicles

: Connector & terminal
(B84) No. 14—Chassis ground:
Is the resistance less than 10Ω?
: Repair ground short circuit in harness between
ECM and idle air control solenoid valve connector.
: Go to next.
: Is there poor contact in idle air control sole-
noid valve connector?
: Repair poor contact in idle air control solenoid
valve connector.
: Contact with SOA service.
NOTE:
Inspection by DTM is required, because probable cause is
deterioration of multiple parts.
288
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

B2M0589A
10BY1
CHECK INPUT SIGNAL FOR ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM and chassis ground.
: Connector & terminal
(B84) No. 82 (+)—Chassis ground ():
Is the voltage between 4.5 and 5.5 V in neu-
tral position?
: Go to next.
: Go to step10BY2.
B2M0589A
: Connector & terminal
(B84) No. 82 (+)—Chassis ground ():
Is the voltage less than1Vinother posi-
tions?
: Go to next.
: Go to step10BY2.
: Is there poor contact in ECM connector?
: Repair poor contact in ECM connector.
: Contact with SOA service.
NOTE:
Inspection by DTM is required, because probable cause is
deterioration of multiple parts.
332
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10. Diagnostic Chart with Trouble Code for LHD Vehicles

: Repair poor contact in ECM connector.
: Contact with SOA service.
NOTE:
Inspection by DTM is required, because probable cause is
deterioration of multiple parts.
OBD0488A
10CA2CHECK HARNESS BETWEEN ECM AND
PRESSURE SOURCES SWITCHING
SOLENOID VALVE CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from pressure sources switching
solenoid valve and ECM.
3) Measure resistance of harness between pressure
sources switching solenoid valve connector and engine
ground.
: Connector & terminal
(B1) No. 1—Engine ground:
Is the resistance less than 10Ω?
: Repair ground short circuit in harness between
ECM and pressure sources switching solenoid
valve connector.
: Go to next step 4).
B2M0597A
4) Measure resistance of harness between ECM and pres-
sure sources switching solenoid valve connector.
: Connector & terminal
(B84) No. 15—(B1) No. 1:
Is the resistance less than 1Ω?
: Go to step10CA3.
: Repair open circuit in harness between ECM and
pressure sources switching solenoid valve con-
nector.
B2M1120
10CA3CHECK PRESSURE SOURCES SWITCH-
ING SOLENOID VALVE.
Measure resistance between pressure sources switching
solenoid valve connector terminals.
: Terminals
No. 1—No. 2:
Is the resistance between 10 and 100Ω?
: Go to step10CA4.
341
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

: Replace pressure sources switching solenoid
valve.
OBD0676A
10CA4CHECK POWER SUPPLY TO PRESSURE
SOURCES SWITCHING SOLENOID
VA LV E .
1) Turn ignition switch to ON.
2) Measure voltage between pressure sources switching
solenoid valve harness connector and engine ground.
: Connector & terminal
(B1) No. 2 (+)—Engine ground ():
Is the voltage more than 10 V?
: Go to next.
: Repair open circuit in harness between main relay
and pressure sources switching solenoid valve
connector.
: Is there poor contact in pressure sources
switching solenoid valve connector?
: Repair poor contact in pressure sources switching
solenoid valve connector.
: Contact with SOA service.
NOTE:
Inspection by DTM is required, because probable cause is
deterioration of multiple parts.
342
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles