sensor SUBARU LEGACY 1995 Service Repair Manual

B5M0098
2) Remove four bolts and then carefully remove airbag
module.
3) Refer to“CAUTION”for handling of a removed airbag
module.
B: INSTALLATION
Installation is in reverse order of removal procedures.
Observe the following: Make sure that ignition switch is off.
CAUTION:
Do not allow harness and connectors to interfere or
get caught with other parts.
G5M0291
4. Front Sensor
CAUTION:
If the front end of the vehicle body is damaged by a
collision, be sure to check the left and right front
sensors, even if the airbag was not inflated. If any dam-
age to the sensor or any deformation of the sensor
mount is found, replace with a new genuine part.
G5M0310
When painting or performing sheet metal work on
the front part of vehicle body, including the front wheel
apron, front fender and front side frame, take utmost
care not to apply dryer heat, painting mist, or the flame
of the welding burner directly to the front sensors and
wire harness of the airbag system.
A: REMOVAL
1) Turn ignition switch off.
2) Disconnect ground cable from battery and wait for at
least 20 seconds before starting work.
13
5-5SERVICE PROCEDURE
3. Airbag Module - 4. Front Sensor

G5M0312
3) Remove lower cover.
Disconnect airbag connector (AB3) and (AB8) below steer-
ing column.
CAUTION:
Do not reconnect airbag connector at steering column
until front sensors are securely re-installed.
G5M0313
4) Remove console box. Discon-
nect 2-pin blue connector (AB4) (right side front sensor)
and 2-pin orange connector (AB5) (left side front sensor)
from airbag control module.
G5M0314
5) Roll up floor mat and side sill cover. [W5A10].> Remove front sensor harness from clip and pro-
tector.
6) Remove front wheels.
7) Remove front mud guard.
G5M0315
8) Remove wiring harness clips.
G5M0316
9) Remove grommet.
14
5-5SERVICE PROCEDURE
4. Front Sensor

B5M0102
10) Remove front sensor.
B: INSTALLATION
Installation is in reverse order of removal procedures.
5. Main Harness
A: REMOVAL
1) Turn ignition switch off.
2) Disconnect ground cable from battery and wait for at
least 20 seconds before starting work.
G5M0312
3) Remove lower cover.
Disconnect airbag connector (AB3) and (AB8) below steer-
ing column.
CAUTION:
Do not reconnect airbag connector at steering column
until main harness are securely re-installed.
G5M0313
4) Remove console box. Discon-
nect 12-pin yellow connector (AB6) from airbag control
module.
15
5-5SERVICE PROCEDURE
4. Front Sensor - 5. Main Harness

B5M0102
10) Remove front sensor.
B: INSTALLATION
Installation is in reverse order of removal procedures.
5. Main Harness
A: REMOVAL
1) Turn ignition switch off.
2) Disconnect ground cable from battery and wait for at
least 20 seconds before starting work.
G5M0312
3) Remove lower cover.
Disconnect airbag connector (AB3) and (AB8) below steer-
ing column.
CAUTION:
Do not reconnect airbag connector at steering column
until main harness are securely re-installed.
G5M0313
4) Remove console box. Discon-
nect 12-pin yellow connector (AB6) from airbag control
module.
15
5-5SERVICE PROCEDURE
4. Front Sensor - 5. Main Harness

14. Vehicle Speed Sensor 2
A: GENERAL PRECAUTIONS
1) Be careful not to drop or bump sensor as this may break
built-in magnet.
2) Drive key is designed to separate from vehicle speed
sensor 2. Be careful not to lose it or forget to install.
3) Vehicle speed sensor 2 is installed in part (which con-
tains bearings, etc., finished to a high degree of accuracy).
Do not allow foreign matter (filings, sand, etc.) to get into
it.
4) When checking output of vehicle speed sensor 2 as a
single unit, ensure test leads are connected to their correct
terminals. Failure to do this may damage internal IC.
5) Discard vehicle speed sensor 2 after removal; replace
with new one.
B: REMOVAL
CAUTION:

Be careful when removing vehicle speed sensor 2
immediately after driving vehicle for a while, as tem-
perature around it is high.

Before removing vehicle speed sensor 2, clean dirt,
etc. from surrounding areas. Take care not to allow
foreign matter to get into mounting hole.
B2M0211
1) Remove collector cover.
2) Disconnect vehicle speed sensor 2 connector.
3) Turn and remove vehicle speed sensor 2.
4) Remove key and packing.
35
6-2SERVICE PROCEDURE
14. Vehicle Speed Sensor 2

C: INSTALLATION
CAUTION:

Ensure sensor mounting hole is clean and free of
foreign matter.

Apply grease to tip end of key to prevent key from
falling off sensor.

Align tip end of key with key groove on end of
speedometer shaft during installation.
1) Hand tighten vehicle speed sensor 2, then tighten it
using suitable tool.
Tightening torque required for sensor to reach bottom of
transmission is as follows:
Tightening torque:
0.39—0.88 N⋅m (4.0—9.0 kg-cm, 3.5—7.8 in-lb)
CAUTION:

When torque must be applied that exceeds 0.88 N⋅m
(9.0 kg-cm, 7.8 in-lb), the key and key groove on end of
speedometer may not be aligned properly. Remove the
key, align it correctly and reassemble.

Sensor threads are secured by Locktite. The reas-
sembly must be completed within 5 minutes before
Locktite dries.
2) Tighten vehicle speed sensor 2 further to specified
torque.
Tightening torque:
5.9±1.5 N⋅m (60±15 kg-cm, 52±13 in-lb)
36
6-2SERVICE PROCEDURE
14. Vehicle Speed Sensor 2

3. Combination Meter
A: DIAGNOSTICS PROCEDURE
If speedometer does not operate, or operates abnormally,
check combination meter circuit (shown in flow chart as
described below).
CAUTION:
Make sure that trouble code of vehicle speed sensor 2
system appears in electrical system on-board diagno-
sis.
Speedometer does not operate, or operates
abnormally.
1. Check power supply for combination meter.
OK
Not OK

Check for disconnection of the combination meter
connector terminal.

Check for open circuit between combination meter
and battery.
,Repair or replace wiring harness.
2. Check ground circuit of combination meter.
OK
Not OK
Repair or replace wiring harness.
3. Check harness connector between
combination meter and vehicle speed sensor
2.
OK
Not OK
Repair or replace wiring harness.
4. Check vehicle speed sensor 2.
OK
Not OK
Replace vehicle speed sensor 2.
Failure of the speedometer.





70
6-2DIAGNOSTICS
3. Combination Meter

B6M0530A
1. CHECK POWER SUPPLY FOR COMBINATION
METER.
1) Remove combination meter.
2) Turn ignition switch to ON.
3) Measure voltage at combination meter connector termi-
nal.
Connector & terminal / Specified voltage:
(i14) No. 11—Body / 10 V, or more
B6M0252B
2. CHECK GROUND CIRCUIT OF COMBINATION
METER.
1) Turn ignition switch to OFF.
2) Measure resistance of harness connector between
combination meter and body.
Connector & terminal / Specified voltage:
(i12) No. 1—Body / 10Ω, max.
B6M0294B
3. CHECK HARNESS CONNECTOR BETWEEN
COMBINATION METER AND VEHICLE SPEED
SENSOR 2.
1) Disconnect connector from vehicle speed sensor 2.
2) Measure resistance of harness connector between
vehicle speed sensor 2 and combination meter.
Connector & terminal / Specified resistance:
(B17) No. 1—(i11)No.2/10Ω, max.
(B17) No. 2—(i11)No.3/10Ω, max.
4. CHECK VEHICLE SPEED SENSOR 2.
NOTE:

If resistance between terminals of vehicle speed sensor
2 is out of specification, the sensor may have a failure.

If resistance is OK and voltage between terminals of
vehicle speed sensor 2 is out of specification, mechanical
trouble may be present between vehicle speed sensor 2
and speedometer shaft in transmission.
71
6-2DIAGNOSTICS
3. Combination Meter

B3M0289
1) Disconnect connector from vehicle speed sensor 2.
2) Measure resistance between terminals of vehicle speed
sensor 2.
Terminals / Specified resistance:
No. 1—No. 2 / 350—450Ω
B3M0256
WARNING:
Be careful not to be caught up by the running wheels.
3) Set the vehicle on free roller, or lift-up the vehicle and
support with safety stands.
4) Drive the vehicle at speed greater than 20 km/h (12
MPH).
5) Measure voltage between terminals of vehicle speed
sensor 2.
Terminals / Specified voltage:
No. 1—No.2/5V,min. (AC range)
B3M0257

Using an oscilloscope:
(1) Turn ignition switch to OFF.
(2) Set oscilloscope to vehicle speed sensor 2.
(3) Drive the vehicle at speed greater than 20 km/h (12
MPH).
(4) Measure signal voltage.
Specified voltage (V): 5 V, min.
B3M0254A
72
6-2DIAGNOSTICS
3. Combination Meter

1. General
1. GENERAL DESCRIPTION

The on-board diagnostics (OBD) system detects and
indicates a fault in various inputs and outputs of the com-
plex electronic control. CHECK ENGINE malfunction indi-
cator lamp (MIL) in the combination meter indicates occur-
rence of a fault or trouble.

Further, against such a failure or sensors as may disable
the drive, the fail-safe function is provided to ensure the
minimal driveability.

The OBD system incorporated with the vehicles within
this engine family complies with Section 1968.1, California
Code of Regulations (OBD-II regulation). The OBD system
monitors the components and the system malfunction
listed in Engine Section which affects on emissions.

When the system decides that a malfunction occurs, MIL
illuminates. At the same time of the MIL illumination or
blinking, a diagnostic trouble code (DTC) and a freeze
frame engine conditions are stored into on-board com-
puter.

The OBD system stores freeze frame engine condition
data (engine load, engine coolant temperature, fuel trim,
engine speed and vehicle speed, etc.) into on-board com-
puter when it detects a malfunction first.

If the OBD system detects the various malfunctions
including the fault of fuel trim or misfire, the OBD system
first stores freeze frame engine conditions about the fuel
trim or misfire.

When the malfunction does not occur again for three
trips, MIL is turned off, but DTC remains at on-board com-
puter.

The OBD-II system is capable of communication with a
general scan tool (OBD-II general scan tool) formed by ISO
9141 CARB.

The OBD-II diagnostics procedure is different from the
usual diagnostics procedure. When troubleshooting OBD-II
vehicles, connect Subaru select monitor or the OBD-II gen-
eral scan tool to the vehicle.
A: ENGINE
1. ENGINE AND EMISSION CONTROL SYSTEM

The Multipoint Fuel Injection (MFI) system is a system
that supplies the optimum air-fuel mixture to the engine for
all the various operating conditions through the use of the
latest electronic technology.
With this system fuel, which is pressurized at a constant
pressure, is injected into the intake air passage of the cyl-
inder head. The injection quantity of fuel is controlled by an
intermittent injection system where the electro-magnetic
injection valve (fuel injector) opens only for a short period
of time, depending on the quantity of air required for one
cycle of operation. In actual operation, the injection quan-
2
2-7ON-BOARD DIAGNOSTICS II SYSTEM
1. General