1997 SUBARU LEGACY service

BRAKES
44

Page

S
SPECIFICATIONS
AND
SERVICE
DATA

1
.
Brakes

C
COMPONENT
PARTS
...........
.
.
.
.....................
.
.
......
..
.
.
.
..........................

1
.
FrontDisc
Brake

2
.
Rear
Disc
Brake

3
.
Rear
Drum
Brake

4
.
Master
Cylinder

5
.
Brake
Booster

6
.
ABS
System
7
.
Hill
Holder

8
.
Parking
(Hand)
Brake
9
.
ABS/TCS
System

10
.
ABS
System(ABS
5
.3i
Type)
...
....
.
...
..........................
.
.
...
.
.............

W
SERVICE
PROCEDURE
...............
.
.
......
.
.
...
.
....................
.
.
.
.
.
.
...
.
...
.
.......

1
.
Front
Disc
Brake
2
.
Rear
Disc
Brake

3
.
Rear
Drum
Brake
4
.
Parking
Brake
(Rear
Disc
Brake)
5
.
Master
Cylinder

6
.
Brake
Booster

7
.
Brake
Hose
8
.
Hill
Holder

9
.
Parking
Brake
Lever

10
.
Parking
Brake
Cable

11
.
Air
Bleeding
(Without
TCS
model)

12
.
Brake
Fluid
Replacement

13
.
Proportioning
Valve

14
.
ABS
Sensor

15
.
Hydraulic
Unit
for
ABS
System

16
.
ABS
Control
Module

17
.
G
Sensor
for
ABS
System

18
.
Brake
Hose
and
Pipe
am
.
.
.....
.
.................................
.
.
...
.
.....
..

19
.
Air
Bleeding
(With
TCS
model)

20
.
Hydraulic
Unit
for
ABS/TCS
System

21
.
ABS/TCS
Control
Module

22
.
Hydraulic
Unit
for
ABS
System
(ABS
5
.3
Type)

23
.
ABS
Control
Module
(ABS
5
.3
Type)

24
.
G
Sensor
for
ABS
System
(ABS
5
.3
Type)

25
.
ABS
Control
Module
and
Hydraulic
Control
Unit
(ABSCM&H/U)
[ABS
5
.3i
Type]
.
.
.
.
.
.
.
...
.
.
.
.
.
..
.
.
...................................
.
...
.
.
.........
..........
26
.
ABS
Sensor
(ABS
5
.3i
Type)
....
...........................................
.
.
....
.
...
.
27
G
Sensor
(ABS
5
3i
T
e)

2

....
.2

....
.4

........
.
.
..
.4

....
..
.15

....
..
.15
yp
....
.
.
......
...
.
...................................
.
.
.
.
.......
.
.
.....

K
DIAGNOSTICS

1
.
Entire
BrakeSystem

2
.
Hill
Holder

PRECAUTION
FORSUPPLEMENTAL
RESTRAINT
SYSTEM
"AIRBAG"
The
Supplemental
Restraint
System
"Airbag"
helps
to
reduce
the
risk
or
severity
of
injury
to
the
driver
in
a
frontal
collision
.
The
Supplemental
Restraint
System
consists
of
an
airbag
module
(located
in
the
center
of
the
steer-
ing
wheel),sensors,
a
control
module,warning
light,
wiring
harness
and
roll
connector
.
Information
necessary
to
servicethe
safety
is
included
in
the"5-5
.
SUPPLEMENTAL
RESTRAINT
SYSTEM"
ofthis
Service
Manual
.
WARNING
:
"
To
avoid
rendering
the
Airbag
system
inoperative,
which
could
lead
to
personal
injury
or
death
in
the
event
of
a
severe
frontal
collision,
all
maintenance
must
be
performed
byan
authorized
SUBARU
dealer
.
"
Improper
maintenance,
including
incorrect
removal
and
installation
of
the
Airbag
system,
can
lead
to
personal
injury
caused
by
unintentional
activation
of
the
Airbag
system
.
"
All
Airbag
system
electrical
wiring
harnesses
and
connectors
are
covered
with
yellow
outer
insu-
lation
.
Do
not
use
electrical
test
equipment
on
any
circuit
relatedtothe
Supplemental
Restraint
System
"Airbag"
.

4-4
twisoot
SERVICE
PROCEDURE
18
.
Brake
Hose
and
Pipe

18
.
Brake
Hoseand
Pipe

SUPPLEMENTAL
RESTRAINT
SYSTEM
"AIRBAG"

Airbagsystem
wiring
harness
is
routed
near
the
center

brake
pipe
.

CAUTION
:

All
Airbag
system
wiring
harness
and
connectors
are

colored
yellow
.
Do
not
use
electrical
test
equipment
on

these
circuit
.

o
Be
careful
not
to
damage
Airbag
system
wiring
har-

ness
when
servicing
thecenter
brake
pipe
.

A
:
REMOVAL
AND
INSTALLATION

CAUTION
:

When
removing
and
installing
the
brake
pipe,
make

sure
that
it
is
notbent
.

"
After
installing
the
brake
pipe
and
hose,bleed
the
air
.

"
After
installing
the
brake
hose,
make
sure
that
if
does

not
touch
the
tire
or
suspension
assembly,
etc
.

4

SERVICE
PROCEDURE
[W18A5]
4-4
18
.
Brake
Hose
and
Pipe
5
.
MODELS
WITH
ABS
(ABS
5
.3i
TYPE)

B4M1221A

Union
bolt
~2
Front
brake
hose
RH

~3
Clip

~4
Valve
bracket

~5
Proportioning
valve

06
Front
brake
pipe
ASSY

~7
Front
brake
hose
LH

(V
Two-way
connector

Connector
bracket

~o
Rear
brake
hose
RH

Rear
brake
pipe
ASSY

~z
Rear
brake
hose
LH

Center
brake
pipe
ASSY

'
41

Tightening
torque
:
N~m
(kg-m,
ft-115)
TI
:
13f3
(1
.3f0
.3,
9
.4f2
.2)
T2
:
15±z(1
.5-0z,
10
.8±a)
T3
:
18f3
(1
.8f0
.3,
13
.0±
2
.2)
T4
:
18±
5
(1
.8
f
0
.5,
13
.0
f3
.6)

5

4-4
[w2soo1
SERVICE
PROCEDURE

25
.
ABS
Control
Module
and
Hydraulic
Control
Unit
(ABSCM&H/U)
[ABS
5
.3i
Type]

25
.
ABS
Control
Module
and
Hydraulic

Control
Unit
(ABSCM&H/U)
[ABS
5
.31

Type]

2
~D

/
T1

2
1
r~

\Y'

0

T1
Q

T2

I
III

B4M1220A
I

Stud
boltO6
Front-RH
outlet

~2
Damper
~7
Primary
inlet

~3
ABS
control
module
and
hydraulic
~8
Rear-LH
outlet

control
unit~9
Rear-RH
outlet
~4
Front-LH
outlet
~o
Bracket

~5
Secondary
inlet

,,t-

Tightening
torque
:
N~m
(kg-m,
It-Ib)
TI
:
18
f
5
(1
.8
f
0
.5,
13
.0
f3
.6)
T2
:
29f7
(3
.0f0
.7,
21,7f5
.1)
T3
:
32
±
10
(3.3
f
1
.0,
24
f
7)

6

SERVICE
PROCEDURE
[w2sao1
4-4

25
.
ABS
Control
Module
and
Hydraulic
Control
Unit
(ABSCM&H/U)
[ABS
5
.3i
Type]

A
:
REMOVAL

1)
Disconnect
ground
cablefrom
battery
.

2)
Remove
air
intake
duct
fromengine
compartment
to

facilitate
removal
of
ABSCM&H/U
.

3)
Use
an
air-gun
to
get
rid
of
water
around
the

ABSCM&H/U
.

CAUTION
:

The
contact
will
be
insufficient
if
the
terminal
gets
wet
.

4)
Pull
on
the
lock
of
the
ABSCM&H/U
connector
to

remove
it
.

5)
Disconnect
connector
from
ABSCM&H/U
.

CAUTION
:

Be
careful
not
tolet
water
or
other
foreign
matter
con-

tact
the
ABSCM&H/U
terminal

6)
Unlock
cable
clip
.

7)
Disconnect
brake
pipes
from
ABSCM&H/U
.

CAUTION
:

Wrap
brake
pipes
with
vinyl
bag
to
avoid
spilling
brake

fluid
on
vehicle
body
.

8)
Remove
ABSCM&H/U
fromengine
compartment
.

CAUTION
:

9
ABSCM&H/U
cannotbe
disassembled
.
Do
not
attempt

to
loosen
bolts
and
nuts
.

"
Do
not
drop
or
bump
ABSCM&H/U
.

"
Do
not
turn
the
ABSCM&H/U
upside
down
or
place
it

on
its
side
.

*
Be
careful
to
prevent
foreign
particles
from
getting

into
ABSCM&H/U
.

9
Apply
acoat
of
rust-preventive
wax
(Nippeco
LT
or

GB)
to
bracket
attaching
bolt
after
tightening
.

*
Do
not
pull
harness
disconnecting
harness
connector
.

7

4-4
[w2sBO]
SERVICE
PROCEDURE

25
.
ABS
Control
Module
and
Hydraulic
Control
Unit
(ABSCM&H/U)
[ABS
5
.3i
Type]

B
:
INSPECTION

i
Mark

>
ABSCM&H/U
B4M
1248A

/Pressure
ga
u
ge
\
'
/\

B4M0633A

1)
Check
connected
and
fixed
condition
of
connector
.

2)
Check
specifications
of
the
mark
with
ABSCM&H/U
.

Mark
Model

C3
AWD
AT

C4
AWD
MT

C
:
CHECKING
THE
HYDRAULIC
UNIT
ABS

OPERATION

1
.
CHECKINGTHE
HYDRAULIC
UNIT
ABS
OPERATION

BY
PRESSURE
GAUGE

1)
Lift-up
vehicle
and
remove
wheels
.

2)
Disconnect
the
air
bleeder
screwsfrom
the
FL
andFR

caliper
bodies
.

3)
Connect
two
pressure
gauges
to
the
FL
andFR
cali-

perbodies
.

CAUTION
:

Pressure
gauges
used
exclusively
for
brake
fluid

must
be
used
.

e
Do
not
employ
pressure
gauge
previously
used
for

transmission
since
the
piston
seal
is
expanded
which

may
lead
to
malfunction
of
the
brake
.

NOTE
:

Wrap
sealing
tape
around
the
pressure
gauge
.

8

SERVICE
PROCEDURE
[w2scI]
4-4

25
.
ABS
Control
Module
and
Hydraulic
Control
Unit
(ABSCM&H/U)
[ABS
5
.3i
Type]

4)
Bleed
air
from
the
pressure
gauges
.

5)
Perform
ABS
sequence
control
.

Ref
.
to
[W25D0]
.*10
>

6)
When
thehydraulic
unit
begins
to
work,
and
first
the

FL
side
performs
decompression,
holding,
and

compression,
and
then
the
FR
side
performs

decompression,
holding,
and
compression
.

7)
Read
values
indicated
on
the
pressure
gauge
and

check
if
the
fluctuationof
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/cmz,
498
psi)
490kPa
(5
kg/cm2,
71
psi)
3,432
kPa
(35
kg/cm2,
498
psi)

or
less
or
more

Rear
wheel
3,432
kPa
(35
kg/cm2,
498
psi)
490kPa
(5
kg
/cm2,
71
psi)
3,432
kPa
(35
kg/cm2,
498
psi)

or
less
or
more

8)
Remove
pressure
gauges
from
FL
and
FR
caliper
bod-

ies
.

9)
Remove
air
bleeder
screws
from
the
RL
andRR
caliper

bodies
.

10)
Connect
the
air
bleeder
screws
to
the
FL
and
FR
cal-

iper
bodies
.

11)
Connect
two
pressure
gauges
to
the
RL
and
RR
cal-
iper
bodies
.

12)
Bleed
air
from
the
pressure
gauges
and
the
FL
and

FR
caliper
bodies
.

13)
Perform
ABS
sequence
control
.

<
Ref
.
to
[W25D0]
.*10
>

14)
When
thehydraulic
unit
begins
to
work,
at
first
the
RR

side
performs
decompression,
holding,
and
compression,

and
then
the
RL
side
performs
decompression,
holding,

and
compression
.

15)
Read
values
indicated
on
the
pressure
gauges
and

check
if
they
meet
thestandardvalue
.

16)
After
checking,
remove
the
pressure
gauges
from
cal-

iper
bodies
.

17)
Connect
the
air
bleeder
screws
to
RL
and
RR
caliper

bodies
.

18)
Bleed
air
from
brake
line
.

9

4-4
[wzsc2]
SERVICE
PROCEDURE

25
.
ABS
Control
Module
and
Hydraulic
Control
Unit
(ABSCM&H/U)
(ABS
5
.3i
Type]

{~~Y+)~

_~00

G4M0464

2
.
CHECKINGTHE
HYDRAULIC
UNIT
ABS
OPERATION

WITH
BRAKE
TESTER

1)
In
the
case
of
AWD
AT
vehicles,
install
aspare
fuse
with

the
FWD
connector
in
the
engine
compartment
to
simu-

late
FWD
vehicles
.

2)
Prepare
for
operating
ABS
sequence
control
.
<
Ref,to

[W25D1
]*10
or
[W25D2]
.*10
>

3)
Setthe
front
wheels
orrear
wheels
on
the
brake
tester

and
set
the
select
lever's
position
at
"neutral"
.

4)
Operate
the
brake
tester
.

5)
Perform
ABS
sequence
control
.
<
Ref
.
to
[W25D1]*10

step
1
or
[W25D2]*10
step
1
.
>

6)
Hydraulic
unit
begins
to
work
;
and
check
the
following

working
sequence
.

(1)
The
FL
wheel
performs
decompression,
holding,

and
compression
in
sequence,
and
subsequently
the

FR
wheel
repeats
the
cycle
.

(2)
The
RR
wheel
performs
decompression,
holding,

and
compression
in
sequence,
and
subsequently
the

RL
wheel
repeats
the
cycle
.

7)
Read
values
indicated
on
the
brake
tester
and
check

if
the
fluctuationof
values,
when
decompressed
and

compressed,
meet
the
standard
values
.

Unit
:
N
(kg,
Ib)

Initial
value
When
decompressed
When
compressed

Front
wheel
981
(100,
221)
490
(50,
110)or
less
981
(100,
221)
or
more

Rear
wheel
981
(100,
221)
490
(50,
110)
or
less
981
(100,
221)or
more

8)
After
checking,
also
check
if
any
irregular
brake
pedal

tightness
is
felt
.

10