SUBARU LEGACY 1995 Service Repair Manual

G4M0451
4) Install front ABS sensor on strut and wheel apron
bracket.
Tightening torque:
32±10 N⋅m (3.3±1.0 kg-m, 24±7 ft-lb)
5) Place a thickness gauge between ABS sensor’s pole
piece and tone wheel’s tooth face. After standard clearance
is obtained over the entire perimeter, tighten ABS sensor
on housing to specified torque.
ABS sensor standard clearance:
0.9—1.4 mm (0.035—0.055 in)
Tightening torque:
32±10 N⋅m (3.3±1.0 kg-m, 24±7 ft-lb)
CAUTION:
Check the marks on the harness to make sure that no
distortion exists. (RH: white, LH: yellow)
NOTE:
If the clearance is outside specifications, readjust.
2. REAR ABS SENSOR
1) Install rear tone wheel on hub, then rear housing on
hub.
G4M0445
2) Temporarily install rear ABS sensor on back plate.
CAUTION:
Be careful not to strike ABS sensor’s pole piece and
tone wheel’s teeth against adjacent metal parts during
installation.
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14. ABS Sensor

3) Install rear drive shaft to rear housing and rear differen-
tial spindle.
G4M0453
4) Install rear sensor harness on rear trailing link.
Tightening torque:
32±10 N⋅m (3.3±1.0 kg-m, 24±7 ft-lb)
5) Place a thickness gauge between ABS sensor’s pole
piece and tone wheel’s tooth face. After standard clearance
is obtained over the entire perimeter, tighten ABS sensor
on back plate to specified torque.
ABS sensor standard clearance:
0.7—1.2 mm (0.028—0.047 in)
Tightening torque:
32±10 N⋅m (3.3±1.0 kg-m, 24±7 ft-lb)
CAUTION:
Check the marks on the harness to make sure that no
distortion exists. (RH: white, LH: yellow)
NOTE:
If the clearance is outside specifications, readjust.
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14. ABS Sensor

15. Hydraulic Unit for ABS System
B4M0069A
1Connector

2Cap

3Motor relay

4Valve relay

5Hydraulic control unit

6Front-RH outlet

7Rear-LH outlet
8Rear-RH outlet

9Front-LH outlet

10Primary inlet

11Secondary inlet

12Bracket
Tightening torque: N⋅m (kg-m, ft-lb)
T1: 1.2±0.2
(0.125±0.025, 0.9±0.2)
T2: 18±5 (1.8±0.5, 13.0±3.6)
T3: 29±7 (3.0±0.7, 21.7±5.1)
T4: 32±10 (3.3±1.0, 24±7)
A: REMOVAL
1) Remove air intake duct.
2) Remove canister from engine compartment to facilitate
removal of hydraulic unit.
3) Disconnect brake pipes from hydraulic unit and plug
open joints to prevent entry of foreign particles.
G4M0455
4) Remove nuts and bolts which secure hydraulic unit, and
remove hydraulic unit from engine compartment.
CAUTION:

Hydraulic unit cannot be disassembled. Do not
attempt to loosen bolts and nuts.

Do not drop or bump hydraulic unit.

Do not turn the hydraulic unit upside down or place
it on its side.
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15. Hydraulic Unit for ABS System

Be careful to prevent foreign particles from getting into
hydraulic unit.

When a new hydraulic unit is installed, apply a coat of
rust-preventive wax (Nippeco LT or GB) to bracket attach-
ing bolts after tightening.

Do not pull harness disconnecting harness connector.
B: INSPECTION
1. CHECKING HYDRAULIC UNIT
1) Check connected and fixed condition of connector.
2) Open hydraulic unit relay box and check for discontinu-
ity or short circuits.
Condition Terminal number Standard Diagram Terminal location
Valve relayTurning off
electricity.85—86 93—11 3Ω
G4M0456G4M0457
30—87a 0Ω
30—87
Turning on
electricity between
85 and 86.
(DC 12 V)30—87a
30—87 0Ω
Motor relayTurning off
electricity.85—86 72—88Ω
G4M0458G4M0459
30—87
Turning on
electricity between
85 and 86.
(DC 12 V)30—87 0Ω
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15. Hydraulic Unit for ABS System

2. CHECKING THE HYDRAULIC UNIT OPERATION BY
PRESSURE GAUGE
1) Remove the FL and FR pipes from the hydraulic unit.
G4M0460
2) Connect two pressure gauges to the hydraulic unit.
CAUTION:

Pressure gauges used exclusively for brake fluid
must be used.

Do not employ pressure gauge previously used for
transmission since the piston seal is expanded which
may lead to malfunction of the brake.
3) Bleed air from the pressure gauges.
4) Perform sequence control.
B4M0082A
(1) Connect diagnosis terminals to 3 terminals (K) and
6 terminals (L) of the diagnosis connector beside driver
seat heater unit.
(2) Turn ignition switch ON.
(3) The ABS warning light comes on.
(4) Depress the brake pedal within 0.5 seconds after
the warning light goes out so that the pressure gauge
registers a pressure equal to the initial value.
CAUTION:
Do not depress the clutch pedal.
NOTE:
The engine must not be operating.
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15. Hydraulic Unit for ABS System

5) When the hydraulic unit begins to work, and first the FL
side performs decompression, holding, and compression,
and then the FR side performs decompression, holding,
and compression.
6) Read values indicated on the pressure gauge and
check if the fluctuation of the values between decompres-
sion and compression meets the standard values. Also
check if any irregular brake pedal tightness is felt.
Initial value When decompressed When compressed
Front wheel 3,432 kPa (35 kg/cm
2, 498 psi) 490 kPa (5 kg/cm2, 71 psi) 3,432 kPa (35 kg/cm2, 498 psi)
Rear wheel 3,432 kPa (35 kg/cm
2, 498 psi) 490 kPa (5 kg/cm2, 71psi) 3,432 kPa (35 kg/cm2, 498 psi)

In case of hydraulic unit plunger piston malfunction:
Initial value When decompressed When compressed
Rear right wheel 3,432 kPa (35 kg/cm
2, 498 psi) 490 kPa (5 kg/cm2, 71 psi) 3,432 kPa (35 kg/cm2, 498 psi)
Rear left wheel 3,432 kPa (35 kg/cm
2, 498 psi) 3,432 kPa (35 kg/cm2, 498 psi) 3,432 kPa (35 kg/cm2, 498 psi)
7) Remove pressure gauges and RL and RR pipes from
the hydraulic unit.
8) Connect the FL and FR pipes to the hydraulic unit.
9) Connect two pressure gauges to the hydraulic unit.
10) Bleed air from the pressure gauges and the FL and FR
wheel cylinders.
11) Repeat step 4) procedures.
12) The hydraulic unit begins to work, and simultaneously
the RL and RR wheel cylinders perform decompression,
holding, and compression.
13) Read values indicated on the pressure gauges and
check if they meet the standard value.
14) After checking, remove the pressure gauges from the
RL and RR pipes and connect the RL and RR pipes to the
hydraulic unit, and bleed air.
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15. Hydraulic Unit for ABS System

G4M0462
3. CHECKING THE HYDRAULIC UNIT WITH BRAKE
TESTER
1) In the case of AWD vehicles, install a spare fuse with
the FWD connector in the engine compartment to simulate
FWD vehicles.
B4M0082A
2) Connect diagnosis terminals to 3 terminals (K) and 6
terminals (L) of the diagnosis connector beside driver seat
heater unit.
G4M0464
3) Set the front wheels or rear wheels on the brake tester
and set the select lever’s position at“neutral”.
4) Operate the brake tester.
5) Perform sequence control.
(1) Turn ignition switch ON.
(2) The ABS warning light comes on.
(3) Depress the brake pedal within 0.5 seconds after
the warning light goes out so that the brake tester reg-
isters a pressure equal to the initial value.
CAUTION:
Do not depress the clutch pedal.
NOTE:
The engine must not be operating.
6) Hydraulic unit begins to work; and check the following
working sequence.
(1) The left front wheel performs decompression,
holding, and compression in sequence, and subse-
quently the right front wheel repeats the cycle.
(2) Simultaneously both right and left rear wheel per-
form decompression, holding, and compression in
sequence.
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15. Hydraulic Unit for ABS System

7) Read values indicated on the brake tester and check if
the fluctuation of values, when decompressed and
compressed, meet the standard values.
Initial value When decompressed When compressed
Front wheel 1,961 N (200 kg, 441 lb) 245 N (25 kg, 55 lb) 1,961 N (200 kg, 441 lb)
Rear wheel 686 N (70 kg, 154 lb) 245 N (25 kg, 55 lb) 686 N (70 kg, 154 lb)

In case of hydraulic unit plunger piston malfunction:
Initial value When decompressed When compressed
Rear right wheel 686 N (70 kg, 154 lb) 245 N (25 kg, 55 lb) 686 N (70 kg, 154 lb)
Rear left wheel 686 N (70 kg, 154 lb) 686 N (70 kg, 154 lb) 686 N (70 kg, 154 lb)
8) After checking, also check if any irregular brake pedal
tightness is felt.
9) In case of AWD vehicles, remove the spare fuse from
the FWD connector in the engine compartment to return to
the original AWD state.
C: SEQUENCE CONTROL
Under the sequence control, after the hydraulic unit sole-
noid valve is driven, the operation of the hydraulic unit can
be checked by means of the brake tester or pressure
gauge.
B4M0082A
1. OPERATIONAL GUIDELINES OF THE SEQUENCE
CONTROL
1) Connect diagnosis terminals to 3 terminals (K) and 6
terminals (L) of the diagnosis connector beside driver seat
heater unit.
2) Set the speed of all wheels at 4 km/h (2 MPH) or less.
3) Within 0.5 seconds after the ABS warning lamp goes
out, immediately after the ignition switch is turned to on,
depress the brake pedal and hold.
CAUTION:
Do not depress the clutch pedal.
NOTE:

When the ignition switch is set to on, the brake pedal
must not be depressed.

Engine must not operate.
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15. Hydraulic Unit for ABS System

2. CONDITIONS FOR COMPLETION OF SEQUENCE
CONTROL
1) When the speed of at least one wheel reaches 10 km/h
(6 MPH), the operation is returned to the normal control
mode.
2) When L terminal is separated from ground, the opera-
tion is returned to the normal control mode.
3) When K terminal is separated from ground, the opera-
tion goes to the trouble code display mode.
4) When the brake pedal is released during sequence con-
trol and the braking lamp switch is set to off, the operation
is returned to the normal control mode.
5) After completion of the sequence control, the operation
is returned to the normal control mode.
B4M0116A
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15. Hydraulic Unit for ABS System

G4M0455
D: INSTALLATION
1) Install relay box cover on hydraulic unit.
2) Install hydraulic unit to bracket.
Tightening torque:
18±5 N⋅m (1.8±0.5 kg-m, 13.0±3.6 ft-lb)
3) Tighten bracket and motor ground lead as a unit.
Tightening torque:
32±10 N⋅m (3.3±1.0 kg-m, 24±7 ft-lb)
4) Connect brake pipes to their correct hydraulic unit con-
nections.
Tightening torque:
15
+3
2N⋅m (1.5+0.3
0.2kg-m, 10.8+2.2
1.4ft-lb)
16. ABS Control Module
A: REMOVAL
1) Remove floor mat located under lower right side of front
seat.
G4M0468
2) Remove screw which secure ABS control module from
the body.
G4M0469
3) Disconnect connector from ABS control module.
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15. Hydraulic Unit for ABS System - 16. ABS Control Module