1997 SUBARU LEGACY tire pressure

1. Supplemental Restraint System
“Airbag”
Airbag system wiring harness is routed near the ABS
sensor, ABS control module and hydraulic control unit.
CAUTION:

All Airbag system wiring harness and connectors
are colored yellow. Do not use electrical test equip-
ment on these circuit.

Be careful not to damage Airbag system wiring har-
ness when servicing the ABS sensor, ABS control
module and hydraulic control unit.
2. Pre-inspection
Before performing diagnostics, check the following items
which might affect ABS problems:
A: MECHANICAL INSPECTION
1. POWER SUPPLY
1) Measure battery voltage and specific gravity of electro-
lyte.
Standard voltage: 12 V, or more
Specific gravity: Above 1.260
2) Check the condition of the main and other fuses, and
harnesses and connectors. Also check for proper ground-
ing.
2. BRAKE FLUID
1) Check brake fluid level.
2) Check brake fluid leakage.
3. BRAKE DRAG
Check brake drag.
4. BRAKE PAD AND ROTOR
Check brake pad and rotor.
5. TIRE SPECIFICATIONS, TIRE WEAR AND AIR
PRESSURE
Check tire specifications, tire wear and air pressure. to 4-2 [S1A1], 4-2 [S1A2].>
2
4-4dBRAKES [ABS 5.3i TYPE]
1. Supplemental Restraint System“Airbag”- 2. Pre-inspection

Condition a) Brakes Deceleration : g
Continuous /Intermittent
b) Accelerator Acceleration : g
Continuous /Intermittent
c) Vehicle speed km/h MPH
Advancing
Accelerating
Reducing speed
Low speed
Turning
Others :
d) Tire inflation pressure Front RH tire : kPa
Front LH tire : kPa
Rear RH tire : kPa
Rear LH tire : kPa
e) Degree of wear Front RH tire :
Front LH tire :
Rear RH tire :
Rear LH tire :
f) Genuine parts are used. :Ye s /No
g) Chain is passed around tires. :Ye s /No
h) T tire is used. :Ye s /No
i) Condition of suspension alignment :
j) Loading state :
k) Repair parts are used. :Ye s /No

What :
l) Others :
13
4-4dBRAKES [ABS 5.3i TYPE]
6. Diagnostics Chart for On-board Diagnosis System

8J1CHECK IF THE WHEELS HAVE TURNED
FREELY FOR A LONG TIME.
: Check if the wheels have been turned freely
for more than one minute, such as when the
vehicle is jacked-up, under full-lock corner-
ing or when tire is not in contact with road
surface.
: The ABS is normal. Erase the trouble code.
NOTE:
When the wheels turn freely for a long time, such as when
the vehicle is towed or jacked-up, or when steering wheel
is continuously turned all the way, this trouble code may
sometimes occur.
: Go to step8J2.
8J2
CHECK TIRE SPECIFICATIONS.
: Are the tire specifications correct?
: Go to step8J3.
: Replace tire.
8J3
CHECK WEAR OF TIRE.
: Is the tire worn excessively?
: Replace tire.
: Go to step8J4.
8J4
CHECK TIRE PRESSURE.
: Is the tire pressure correct?
: Go to step8J5.
: Adjust tire pressure.
8J5CHECK INSTALLATION OF ABS SEN-
SOR.
Tightening torque:
32±10 N⋅m (3.3±1.0 kg-m, 24±7 ft-lb)
: Are the ABS sensor installation bolts tight-
ened securely?
: Go to step8J6.
: Tighten ABS sensor installation bolts securely.
43
4-4dBRAKES [ABS 5.3i TYPE]
8. Diagnostics Chart with Trouble Code by ABS Warning Light

10M1CHECK IF THE WHEELS HAVE TURNED
FREELY FOR A LONG TIME.
: Check if the wheels have been turned freely
for more than one minute, such as when the
vehicle is jacked-up, under full-lock corner-
ing or when tire is not in contact with road
surface.
: The ABS is normal. Erase the trouble code.
NOTE:
When the wheels turn freely for a long time, such as when
the vehicle is towed or jacked-up, or when steering wheel
is continuously turned all the way, this trouble code may
sometimes occur.
: Go to step10M2.
10M2
CHECK TIRE SPECIFICATIONS.
Turn ignition switch to OFF.
: Are the tire specifications correct?
: Go to step10M3.
: Replace tire.
10M3
CHECK WEAR OF TIRE.
: Is the tire worn excessively?
: Replace tire.
: Go to step10M4.
10M4
CHECK TIRE PRESSURE.
: Is the tire pressure correct?
: Go to step10M5.
: Adjust tire pressure.
10M5CHECK INSTALLATION OF ABS SEN-
SOR.
Tightening torque:
32±10 N⋅m (3.3±1.0 kg-m, 24±7 ft-lb)
: Are the ABS sensor installation bolts tight-
ened securely?
: Go to step10M6.
: Tighten ABS sensor installation bolts securely.
120
4-4dBRAKES [ABS 5.3i TYPE]
10. Diagnostics Chart with Select Monitor

11. General Diagnostics Table
A: SYMPTOMS AND PROBABLE CAUSES
Symptom Probable faulty units/parts
Vehicle instability during brakingVehicle pulls to either side.
ABSCM&H/U (solenoid valve)

ABS sensor

Brake (caliper & piston, pads)

Wheel alignment

Tire specifications, tire wear and air pressures

Incorrect wiring or piping connections

Road surface (uneven, camber)
Vehicle spins.
ABSCM&H/U (solenoid valve)

ABS sensor

Brake (pads)

Tire specifications, tire wear and air pressures

Incorrect wiring or piping connections
Poor brakingLong braking/stopping distance
ABSCM&H/U (solenoid valve)

Brake (pads)

Air in brake line

Tire specifications, tire wear and air pressures

Incorrect wiring or piping connections
Wheel locks.
ABSCM&H/U (solenoid valve, motor)

ABS sensor

Incorrect wiring or piping connections
Brake dragging
ABSCM&H/U (solenoid valve)

ABS sensor

Master cylinder

Brake (caliper & piston)

Parking brake

Axle & wheels

Brake pedal play
Long brake pedal stroke
Air in brake line

Brake pedal play
Vehicle pitching
Suspension play or fatigue (reduced damping)

Incorrect wiring or piping connections

Road surface (uneven)
Unstable or uneven braking
ABSCM&H/U (solenoid valve)

ABS sensor

Brake (caliper & piston, pads)

Tire specifications, tire wear and air pressures

Incorrect wiring or piping connections

Road surface (uneven)
Vibration and/or noise (while
driving on slippery roads)Excessive pedal vibration
Incorrect wiring or piping connections

Road surface (uneven)
Noise from ABSCM&H/U
ABSCM&H/U (mount bushing)

ABS sensor

Brake piping
Noise from front of vehicle
ABSCM & H/U (mount bushing)

ABS sensor

Master cylinder

Brake (caliper & piston, pads, rotor)

Brake piping

Brake booster & check valve

Suspension play or fatigue
Noise from rear of vehicle
ABS sensor

Brake (caliper & piston, pads, rotor)

Parking brake

Brake piping

Suspension play or fatigue
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4-4dBRAKES [ABS 5.3i TYPE]
11. General Diagnostics Table