1995 SUBARU LEGACY ignition switch

4
CHECK HARNESS.
1) Turn ignition switch to OFF.
2) Disconnect connector from rear oxygen sensor.
3) Turn ignition switch to ON.
OBD0707A
4) Measure voltage between rear oxygen sensor harness
connector and body.
: Connector & terminal
(T6) No. 4—Body/0.2 V, or more
: Repair harness and connector.
NOTE:
In this case, the following are the possible causes.

1Open circuit of harness between rear oxygen sensor
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.
5
CHECK EXHAUST SYSTEM.
: Check the following items.

Looseness of installation portions

Damage (crack, hole etc.) of parts

Looseness and opening of parts between
front oxygen sensor and rear oxygen sen-
sor.
: Repair or replace faulty parts.
: Replace rear oxygen sensor.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

OBD0145A
1CONNECT 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.
OBD0708
5) Read data on Subaru Select Monitor or OBD-II general
scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F30

F30: Rear oxygen sensor heater current is indicated.
: Is the reading of F30 0.2 A, or more?
: Go to step 2.
: Repair connector.
NOTE:
In this case, poor contact of rear oxygen sensor connector
and ECM connector can be the possible cause.

OBD-II scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
OBD0709A
2CHECK OUTPUT SIGNAL FROM ECM. (USING
VOLTAGE METER.)
1) Start and idle the engine.
2) Measure voltage between ECM and body.
: Connector & terminal
(B84) No. 43—Body/1.0 V, or less
: Go to step 3.
: Go to next.
: Is the voltage less than 1.0 V while shaking
harness and connector of ECM?
: Repair poor contact in ECM connector.
: Go to next step.
196
2-7ON-BOARD DIAGNOSTICS II SYSTEM
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
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

1
CHECK EXHAUST SYSTEM.
: Are there holes or loose bolts on exhaust
system?
: Repair exhaust system.
: Go to step 2.
2
CHECK AIR INTAKE SYSTEM.
: Are there holes, loose bolts or disconnec-
tion of hose on air intake system?
: Repair air intake system.
: Go to step 3.
B2M0047
3
CHECK FUEL PRESSURE.
1) Release fuel pressure.
(1) Remove fuel pump access hole lid located on the
right rear of trunk compartment floor (Sedan) or lug-
gage compartment floor (Wagon).
(2) Disconnect connector from fuel tank.
(3) Start the engine, and run it until it stalls.
(4) After stopping the engine, crank the engine for 5 to
7 seconds to reduce fuel pressure.
(5) Turn ignition switch to OFF.
B2M0047
2) Connect connector to fuel tank.
199
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

4CHECK ENGINE COOLANT TEMPERATURE
SENSOR.
< REF. TO“F: DTC P0115 [T11F0].”>
1) Turn ignition switch to OFF.
OBD0145A
2) Connect the Subaru Select Monitor or the OBD-II gen-
eral scan tool to data link connector.
3) Start the engine and warm-up completely.
OBD0176
OBD0177
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: F05 or F06

F05: Water temperature is indicated in“°F”.

F06: Water temperature is indicated in“°C”.
: Is temperature indicated on Subaru Select
Monitor (F05) greater than 140°F?
Is temperature indicated on Subaru Select
Monitor (F06) greater than 60°C?
: Go to step 5.
: Replace engine coolant temperature sensor.

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
201
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

OBD0145A
5
CHECK MASS AIR FLOW SENSOR.
1) Turn ignition switch to OFF.
2) Connect the Subaru Select Monitor or the OBD-II gen-
eral scan tool to data link connector.
3) Start the engine and warm-up engine until coolant tem-
perature is greater than 60°C (140°F).
OBD0616
4) Read data on Subaru Select Monitor or OBD-II general
scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F47

F47: Mass air flow is shown on display.
: Is the voltage within the specifications
shown in the following table?
Engine speed Specified value
Idling 1.9—3.6 (g/sec)
2,500 rpm 7.0—14.8 (g/sec)
: Replace mass air flow sensor.
: Contact with SOA service.
Note: Inspection by DTM is required.
Probable cause: Deterioration of plural parts

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
202
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11. Diagnostics Chart with Trouble Code

OBD0712A
1
CHECK OUTPUT SIGNAL FROM ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM connector and body on
faulty cylinders.
: Connector & terminal
#1 (B84) No. 2—Body/10 V, or more
#2 (B84) No. 1—Body/10 V, or more
#3 (B84) No. 18—Body/10 V, or more
#4 (B84) No. 17—Body/10 V, or more
: Go to step 2.
: Go to step 3.
OBD0712A
2
CHECK HARNESS.
1) Turn ignition switch to OFF.
2) Disconnect connector from fuel injector on faulty cylin-
der.
3) Turn ignition switch to ON.
4) Measure voltage between ECM connector and body on
faulty cylinders.
: Connector & terminal
#1 (B84) No. 2—Body/10 V, or more
#2 (B84) No. 1—Body/10 V, or more
#3 (B84) No. 18—Body/10 V, or more
#4 (B84) No. 17—Body/10 V, or more
: Repair short circuit of harness between ECM and
fuel injector. After repair, replace ECM.
: Go to next step.
G2M0464
5) Turn ignition switch to OFF.
6) Measure resistance between fuel injector terminals on
faulty cylinder.
: Terminals
No. 1—No. 2/1Ω, or less
: Replace faulty fuel injector and ECM.
: Go to next.
207
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

: Is there poor contact in ECM connector?
: Repair poor contact in ECM connector.
: Replace ECM.
OBD0713A
3
CHECK HARNESS.
1) Turn ignition switch to OFF.
2) Disconnect connector from fuel injector on faulty cylin-
ders.
3) Measure resistance between fuel injector on faulty cyl-
inders and body.
: Connector & terminal
#1 (E5) No. 1—Body/10Ω, or less
#2 (E16) No. 1—Body/10Ω, or less
#3 (E6) No. 1—Body/10Ω, or less
#4 (E17) No. 1—Body/10Ω, or less
: Repair short circuit of harness between fuel injec-
tor and body.
: Go to the next step.
OBD0714A
4) Measure resistance of harness connector between
ECM connector and fuel injector on faulty cylinders.
: Connector & terminal
#1 (B84) No. 2—(E5) No. 1/10Ω, or less
#2 (B84) No. 1—(E16) No. 1/10Ω, or less
#3 (B84) No. 18—(E6) No. 1/10Ω, or less
#4 (B84) No. 17—(E17) No. 1/10Ω, or less
: Repair open circuit of harness between ECM and
fuel injector.
: Go to step 4.
208
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code