SUBARU LEGACY 1997 Service Owner's Guide

4-4d
[T1oo]
BRAKES
[ABS
5
.31
TYPE]

1
.
Supplemental
Restraint
System
"Airbag"
-
2
.
Pre-inspection

1
.
Supplemental
Restraint
System

"Airbag"

Airbagsystem
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
equipment
on

these
circuit
.

e
Be
careful
not
to
damage
Airbag
system
wiring
har-

ness
when
servicing
the
ABS
sensor,
ABS
control
mod-

ule
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
fluidlevel
.

2)
Check
brake
fluid
leakage
.

3
.
BRAKEDRAG

Check
brake
drag
.
<
Ref
.
to
4-4
[K100].*1
>

4
.
BRAKE
PADAND
ROTOR

Check
brake
padand
rotor
.
<
Ref
.
to
4-4
[K100].*1
>

5
.
TIRE
SPECIFICATIONS,
TIRE
WEARAND
AIR

PRESSURE

Check
tire
specifications,
tire
wear
and
air
pressure
.
<
Ref
.

to
4-2
[S1
A1
],
[S1
A2]
.*1
>

2

4-4d
[T1oo]
BRAKES
[ABS
5
.31
TYPE]

1
.
Supplemental
Restraint
System
"Airbag"
-
2
.
Pre-inspection

1
.
Supplemental
Restraint
System

"Airbag"

Airbagsystem
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
equipment
on

these
circuit
.

e
Be
careful
not
to
damage
Airbag
system
wiring
har-

ness
when
servicing
the
ABS
sensor,
ABS
control
mod-

ule
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
fluidlevel
.

2)
Check
brake
fluid
leakage
.

3
.
BRAKEDRAG

Check
brake
drag
.
<
Ref
.
to
4-4
[K100].*1
>

4
.
BRAKE
PADAND
ROTOR

Check
brake
padand
rotor
.
<
Ref
.
to
4-4
[K100].*1
>

5
.
TIRE
SPECIFICATIONS,
TIRE
WEARAND
AIR

PRESSURE

Check
tire
specifications,
tire
wear
and
air
pressure
.
<
Ref
.

to
4-2
[S1
A1
],
[S1
A2]
.*1
>

2

BRAKES
[ABS
5
.3i
TYPE]
[TZBi]
4-4d

2
.
Pre-inspection

B
:
ELECTRICAL
INSPECTION

1
.
WARNING
LIGHT
ILLUMINATION
PATTERN

START

ON
r~
ON
OFF
Ignition
key
switch

Illuminates
.

Goes
out
.
Goes
out
.
ABS
warning
light1.5s
4
111

B4M0781A

1)
When
the
ABS
warning
light
does
not
illuminate
in

accordance
with
this
illumination
pattern,
there
must
be
an
electrical
malfunction
.

2)
When
the
ABS
warning
light
remains
constantly
OFF,

repair
the
ABS
warning
light
circuit
or
diagnosis
circuit
.

<Ref
.
to
4-4d
[T7A0]
.*10>

NOTE
:

Even
though
the
ABS
warning
light
does
not
go
out
1
.5

seconds
after
it
illuminates,
the
ABS
system
operates
nor-

mally
when
the
warning
light
goes
out
while
driving
at

approximately
12
km/h
(7
MPH)
.
However,
the
Anti-lock

brakes
do
not
work
while
the
ABS
warning
light
is
illumi-

nated
.

3

4-4d
[Taoo1
BRAKES
[ABS
5
.31
TYPE]

3
.
Electrical
Components
Location

3
.
Electrical
Components
Location

84M
1225A

ABS
control
module
and
hydraulic
control
unit

(ABSCM&H/U)
~2
Proportioning
valve

03
Diagnosisconnector

~4
ABS
warning
light

~5
Data
link
connector
(for
Subaru
select
monitor)

~6
Transmission
control
module
(only
AT
vehicle)

Tone
wheel

%
ABS
sensor

Wheel
cylinder

(*
G
sensor
(only
AWD
vehicle)

~t
Brake
switch

#
Master
cylinder

4

BRAKES
[ABS
5
.31
TYPE]
[Mo]
4-4d

3
.
Electrical
Components
Location

O

.a
4

.OeF
r~
~
12p
Y1
"
N,
~
'
o~
~~
m
en
.
7
2
1
O

---~
4

~-
)~
134M1226A
134100230D
I
134M0786C

7I
I
~
~
~l
\

°o

i

5
~-~s~v

'
Diag
.
terminal

3
terminal
6
terminal

B4M0646D
1341002311341002
1)
311)
84M06451)

5

4-4d
[raoo]
BRAKES
[ABS
5
.31
TYPE]

4
.
Schematic

4
.
Schematic

10

14

BATTERY
16

-----I

---
IGN

17
----I

=
O_
.__J

C5
19

U6

--
-
------
H
!
20

-----------
g

10

1
-
~
11

----------
----
r
12
23
`
&#34;
...
.,`
@
.

Twisted
w
ire

B
4M1227A

ABS
control
module
and
hydraulic
control
unit

(ABSCM&H/U)

~2
ABS
control
module
area

~3
Valve
relay

~a
Motor
relay

~5
Motor

06
Front
left
inlet
solenoid
valve

07
Front
left
outlet
solenoid
valve

~8
Front
right
inlet
solenoid
valve

Front
right
outlet
solenoid
valve
~o
Rear
left
inlet
solenoid
valve

Rear
left
outlet
solenoid
valve

g
Rear
right
inlet
solenoid
valve

Rear
right
outlet
solenoid
valve

~a
Transmission
control
module
(only
AT
model)

~5
Diagnosis
connector

~s
Data
link
connector

ABS
warning
light

Qe
Stop
light
switch

Stop
light

~o
G
sensor
(only
AWD
model)

Front
left
ABS
sensor

~2
Front
right
ABS
sensor

Rear
left
ABS
sensor

Rear
right
ABS
sensor

6

4-4d
[TSOi1
BRAKES
[ABS
5
.31
TYPE]

5
.
Control
Module
I/OSignal
5
.
Control
Module
I/O
Signal

1
.
I/O
SIGNAL
VOLTAGE

ABS
control
moduleand
hydraulic
control
unit
connector

Ell

30000000

00000

Connector
switch

i

F49

1
21314
5
1
6
1
7
1
8
1
9
1
10
1
11
1
12
1
13
1
14
1
15

16
171819
20
2122
232425
26
1
27
1
28
1
29
1
30
1
31
1

84M1228A

NOTE
:

*
The
terminal
numbers
in
the
ABS
control
module
and

hydraulic
control
unit
connector
are
as
shown
in
the
fig-

ure
.

9
When
the
connector
is
removed
from
the
ABSCM&H/U,

the
connector
switchcloses
the
circuit
between
terminal

No
.
21
andNo
.
23
.
The
ABS
warning
light
illuminates
.

8

BRAKES
[ABS
5
.31
TYPE]
'
[T501]
4-4d

5
.
Control
Module
I/O
Signal

Terminal

N
Input/Output
signal
Contents
o
.

_)
Measured
value
andmeasuring
conditions

ABS
Front
left
wheel
9-10

sensor'2
Front
right
wheel
11-12
0
.12
-
1
V
(Wheel

speed
Rear
left
wheel
7-8
(When
it
is
20Hz
.)

sensor)
Rear
right
wheel
14-15

Valve
relay
power
supply
24-23
10
-
15
Vwhen
ignition
switch
is
ON
.

Motor
relay
power
supply
25-23
10
-
15
Vwhen
ignition
switch
is
ON
.

G
sensor'2
Power
supply
30-28
4
.75
-
5
.25
V

(AWD
model
ground
28
-

only)
output
6-28
2
.3f0
.2
V
when
vehicle
isin
horizontal
position
.

Stop
light
switch*1
2-23
Less
than
1
.5
V
when
the
stop
light
is
OFF
and,10
-
15
V

when
thestop
light
is
ON
.

ABS
warning
light`2
21-23
Less
than
1.5
V
during
1
.5
seconds
when
ignition
switch
is

ON,and
10
-
15
V
after
1.5
seconds
.

AT
ABS
signal'2

(AT
model
only)
31-23
Less
than
1
.5
V
when
the
ABS
control
does
not
operate
still

and
more
than5
.5
V
when
ABS
operates
.

ABS
operation
signal
monitor*2
3--23
Less
than
1
.5
V
when
the
ABS
control
does
not
operate
still

and
more
than5
.5
V
when
ABS
operates
.

Select
Data
is
received
.
20-23
Less
than
1
.5
V
when
no
data
is
received
.

monitor'2
Data
is
sent
.
5--23
4
.75
-
5
.25
V
when
no
data
is
sent
.

ABS
Terminal
No
.
3
29-23
10
-
15
V
when
ignition
switch
is
ON
.
diagnosis

connector*2
Terminal
No
.
6
4-23
10
-
15
V
when
ignition
switch
is
ON
.

Power
supply'1
1-23
10
-
15
V
when
ignition
switch
is
ON
.

Grounding
line
23
-

Grounding
line
~26

*1
:
Measure
the
I/O
signal
voltage
after
removing
the
connector
from
the
ABSCM&H/U
terminal
.
'2
:
Measure
the
I/O
signal
voltage
at
connector
(F2)
or
(Fi)
.

9

4-4d
[TSOZ]
BRAKES
[ABS
5
.31
TYPE]

5
.
Control
Module
I/O
Signal

2
.
I/O
SIGNAL
DIAGRAM

Ignition
key
switch

84101229A

10

BRAKES
[ABS
5
.31
TYPE]
[rsao]
4-4d

6
.
Diagnostics
Chart
for
On-board
Diagnosis
System

I
TROUBLE
OCCURS
.I

Is
Select
Monitor
available?
I
Yes
1
10
.
Diagnostic
Chart
with
Select
1
Monitor
.

Ask
the
customer
when
and
how
the
trouble
occurred
using
interview
check
list
.

6
.
Diagnostics
Chart
for
On-board

Diagnosis
System

A
:
BASIC
DIAGNOSTICS
PROCEDURE

I
PRE-INSPECTION
I

I
CALLING
UPA
TROUBLE
CODE
.
I

No
trouble
code
is
readable
.
Inspection
using
Diagnostic
Chart
for
Warning
Light
Failure
.

Record
all
trouble
codes
.
Only
the
start
code
is
issued
.

Trouble
codes
are
issued
.

Perform
diagnostics
in
accordance
with
trouble
code
.

Trouble
code
I
Repair
.
designated
.

Clear
memory
.

I
INSPECTION
MODE
I

I
CALLING
UPA
TROUBLE
CODE
.

Only
the
star
t
code
is
issued
.

CONFIRMATION
TEST

END

Inspection
using
General
Diagnostics
chart
.

B4M
1051
A

CAUTION
:

Remove
foreign
matter
(dust,
water,
etc
.)
from
the

ABSCM&H/U
connector
during
removal
and
installation
.

NOTE
:

e
To
check
harness
for
broken
wires
or
short
circuits,

shake
it
while
holding
it
or
the
connector
.

*
When
ABS
warning
light
illuminates,
read
and
record

trouble
code
indicated
by
ABS
warning
light
.

11