1995 SUBARU LEGACY relay

OBD0689A
2CHECK INPUT SIGNAL FOR ECM. (USING
VOLTAGE METER AND SUBARU SELECT
MONITOR.)
Measure voltage between ECM and body while engine is
idling.
: Connector & terminal
(B84) No. 26—Body/0.3 V, or less
: Go to step 3.
: Go to next.
G2M0527
: Is the voltage more than 0.3 V while shaking
harness and connector of ECM and monitor-
ing the value with Subaru select monitor?
: Repair poor contact in ECM connector.
: Replace ECM with a new one.
B2M0623A
3CHECK POWER SUPPLY TO MASS AIR
FLOW SENSOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from mass air flow sensor.
3) Turn ignition switch to ON.
4) Measure voltage between mass air flow sensor connec-
tor and body.
: Connector & terminal
(B3) No. 1—Body/10 V, or more
: Go to step 4.
: Repair open circuit of harness between main relay
connector and mass air flow sensor connector.
139
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11. Diagnostics Chart with Trouble Code

OBD0216A
3) Disconnect connector from front oxygen sensor.
4) Measure voltage between ECM and body.
: Connector & terminal
(B84) No. 44—Body/1.0 V, or less
: Replace ECM.
: Repair short circuit of harness between ECM and
front oxygen sensor connector. After repair short
circuit of harness, replace ECM.
OBD0667A
3CHECK POWER SUPPLY TO FRONT OXYGEN
SENSOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from front oxygen sensor.
3) Turn ignition switch to ON.
4) Measure voltage between front oxygen sensor connec-
tor and body.
: Connector & terminal
(B18) No. 2—Body/10 V, or more
: Go to step 4.
: Repair power supply line.
NOTE:
In this case, repair poor contact in connector or open cir-
cuit of harness between main relay and front oxygen sen-
sor.
OBD0706
4
CHECK FRONT OXYGEN SENSOR.
1) Turn ignition switch to OFF.
2) Measure resistance between front oxygen sensor con-
nector terminals.
: Terminals
No. 1—No. 2/30Ω, or less
: Repair harness and connector.
NOTE:
In this case, repair the following:

1Open circuit of harness between the front oxygen sen-
sor connector and the ECM connector

2Poor contact in front oxygen sensor connector

3Poor contact in ECM connector
: Replace front oxygen sensor.
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11. Diagnostics Chart with Trouble Code

OBD0709A
3) Disconnect connector from rear oxygen sensor.
4) Measure voltage between ECM and body.
: Connector & terminal
(B84) No. 43—Body/1.0 V, or less
: Replace ECM.
: Repair short circuit of harness between ECM and
rear oxygen sensor connector. After repair short
circuit of harness, replace ECM.
OBD0710A
3CHECK POWER SUPPLY TO REAR OXYGEN
SENSOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from rear oxygen sensor.
3) Turn ignition switch to ON.
4) Measure voltage between rear oxygen sensor connec-
tor and body.
: Connector & terminal
(T6) No. 2—Body/10 V, or more
: Go to step 4.
: Repair power supply line.
NOTE:
In this case, repair poor contact in connector or open cir-
cuit of harness between main relay and rear oxygen sen-
sor.
OBD0706
4
CHECK REAR OXYGEN SENSOR.
1) Turn ignition switch to OFF.
2) Measure resistance between rear oxygen sensor con-
nector terminals.
: Terminals
No. 1—No. 2/30Ω, or less
: Repair harness and connector.
NOTE:
In this case, repair the following.

1Open circuit of harness between rear oxygen sensor
connector and ECM connector

2Poor contact in rear oxygen sensor connector

3Poor contact in ECM connector

4Poor contact in rear oxygen sensor connecting harness
connector
: Replace rear oxygen sensor.
197
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11. Diagnostics Chart with Trouble Code

G2M0464
4
CHECK FUEL INJECTOR.
Measure resistance between fuel injector terminals on
faulty cylinder.
: Terminals
No. 1—No. 2/5—20Ω
: Replace faulty fuel injector.
: Go to step 5.
OBD0715A
5
CHECK POWER SUPPLY.
1) Turn ignition switch to ON.
2) Measure voltage between fuel injector and body on
faulty cylinders.
: Connector & terminal
#1 (E5) No. 2—Body/10 V, or more
#2 (E16) No. 2—Body/10 V, or more
#3 (E6) No. 2—Body/10 V, or more
#4 (E17) No. 2—Body/10 V, or more
: Check and repair the following items.

Open circuit of harness between main relay
and fuel injector for faulty cylinders

Poor contact in main relay connector

Poor contact in fuel injector connector for the
faulty cylinders
: Check for poor contact of all connectors in WIR-
ING DIAGRAM on page 205, 206.
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11. Diagnostics Chart with Trouble Code

: Repair short circuit of harness between ECM con-
nector and EGR solenoid valve connector.
: Go to the next step.
OBD0677A
4) Measure resistance of harness connector between
ECM and EGR solenoid valve.
: Connector & terminal
(B84) No. 60—(E18) No. 2 / 10Ω, or less
: Go to step 5.
: Repair open circuit of harness between ECM con-
nector and EGR solenoid valve connector.
OBD0327
5
CHECK EGR SOLENOID VALVE.
Measure resistance between connector terminals of EGR
solenoid valve.
: Terminals
No. 1—No. 2 / 10—100Ω
: Go to step 6.
: Replace EGR solenoid valve.
OBD0328A
6CHECK POWER SUPPLY TO EGR SOLENOID
VA LV E .
1) Turn ignition switch to ON.
2) Measure voltage between EGR solenoid valve harness
connector and body.
: Connector & terminal
(E18) No. 1—Body / 10 V, or more
: Confirm good connection at EGR solenoid valve
connector.
: Repair open circuit of harness between main relay
connector and EGR solenoid valve connector.
239
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11. Diagnostics Chart with Trouble Code

OBD0339A
5CHECK POWER SUPPLY TO PURGE CON-
TROL SOLENOID VALVE.
1) Turn ignition switch to ON.
2) Measure voltage between purge control solenoid valve
connector and body.
: Connector & terminal
(E4) No. 1—Body / 10 V, or more
: Confirm good connection at purge control sole-
noid valve connector.
: Repair open circuit of harness between main relay
connector and purge control solenoid valve con-
nector.
252
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11. Diagnostics Chart with Trouble Code

OBD0676A
6CHECK POWER SUPPLY TO PRESSURE
SOURCES SWITCHING SOLENOID VALVE.
1) Turn ignition switch to ON.
2) Measure voltage between pressure sources switching
solenoid valve harness connector and body.
: Connector & terminal
(B1) No. 2—Body / 10 V, or more
: Confirm good connection at pressure sources
switching solenoid valve connector.
: Repair open circuit of harness between main relay
connector and pressure sources switching sole-
noid valve connector.
324
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11. Diagnostics Chart with Trouble Code

OBD0527
BI: DTC P1500
—RADIATOR FAN RELAY 1 CIRCUIT
MALFUNCTION (FAN
—1)—
DESCRIPTION:

The engine cooling system consists of a down-flow
radiator which features high heat-dissipation performance,
an electric motor fan, an engine coolant pump, a
thermostat, and an engine coolant temperature sensor.

The ON-OFF control of the radiator fan is governed by
the ECM which receives signals sent from the engine cool-
ant temperature sensor. On models which are equipped
with an air conditioning system, the ECM receives signals
sent from the engine coolant temperature sensor, vehicle
speed sensor 2 and A/C switch. These signals simulta-
neously turn ON or OFF the radiator main fan and radiator
sub fan as well as setting them at“HI”or“LO”speed.
[Without A/C models]
Engine coolant temperature signal *1ECM output signal Operation of radiator fan
Radiator fan relay 1 Main
ON ON ON
OFF OFF OFF
*1 ON: Above 95°C (203°F), OFF: Below 89°C (192°F)
[With A/C models]
Engine coolant
temperature
signal *2A/C compressorVehicle speed
signal *3ECM output signal Operation of radiator fan
Radiator fan
relay 1Radiator fan
relay 2Main Sub
ONONON ON ON HI HI
OFF ON ON HI HI
OFFON ON ON HI HI
OFF ON OFF LO LO
OFFONON ON ON HI HI
OFF ON OFF LO LO
OFFON OFF OFF OFF OFF
OFF OFF OFF OFF OFF
*2 ON: Above 95°C (203°F), OFF: Below 89°C (192°F)
*3 ON: Above 20 km/h (12 MPH), OFF: Below 10 km/h (6 MPH)
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11. Diagnostics Chart with Trouble Code