1997 SUBARU LEGACY ignition

BRAKES
IM13-21
4-4
13
.
Anti-lock
Brake
System
(ABS)
[5
.3i
Type]

2
.
FUNCTIONS
OF
SENSORS
AND
ACTUATORS

Name
Function

ABS
control
moduleand
hydraulic
ABSCM-
e
Calculates
and
determine
the
conditionsof
the
wheels
and
body
from
control
unit
(ABSCM&H/U)
section
the
wheel
speedsand
makes
a
proper
decision
suitable
for
the
current
situation
to
control
the
hydraulic
unit
.

In
the
ABS
operation
mode,
the
module
outputs
a
cooperative
control
signal
to
the
AT
control
module
.
(AT
vehicles
only)

Whenever
the
ignition
switch
is
placed
at
ON,
the
module
makes
a
self
diagnosis
.
When
anything
wrong
is
detected,
the
module
cuts
off
the
system
.

Communicates
with
the
Subaru
select
monitor
.

H/U-section
In
the
ABS
operation
mode,
the
H/U
changes
fluid
passages
to
control

the
fluid
pressure
of
the
wheel
cylinders
in
response
to
an
instruction
from
the
ABSCM
.

The
H/U
also
constitutes
thebrake
fluid
passage
from
the
master
cylin-
der
to
the
wheel
cylinders
together
with
pipings
.

Valve
relay-
Serves
asa
power
switch
for
the
solenoid
valve
and
motor
relay
coil
in
section
response
to
an
instruction
from
the
ABSCM
.

Motor
relay-
Serves
as
a
power
switch
for
the
pump
motor
in
response
to
an
instruc-
section
tion
from
the
ABSCM
.

Wheel
speed
sensor
(ABS
sensor)
Detects
the
wheel
speed
in
terms
of
a
change
in
the
magnetic
flux
den-
sity
passingthrough
the
sensor,
converts
it
into
an
electrical
signal,
and
outputs
the
electrical
signal
to
the
ABSCM
.

Tone
wheel
Gives
a
change
in
the
magnetic
flux
density
by
the
teeth
around
the
tone
wheel
to
let
the
ABS
sensor
generate
an
electrical
signal
.

G
sensor
(AWD
vehicle
only)
Detects
a
change
in
G
in
the
longitudinal
direction
of
the
vehicle
and
outputs
it
to
the
ABSCM
in
terms
of
a
change
in
voltage
.

Stop
light
switch
Transmits
the
information
on
whether
the
brakepedal
is
depressed
or
not
to
the
ABSCM
for
use
as
a
condition
in
determining
ABS
operation
.

ABS
warning
light
Alerts
the
driver
to
an
ABS
fault
.
When
the
diagnosis
connector
and
diagnosis
terminal
are
connected,
the
light
flashes
to
indicate
a
trouble
codes
in
response
to
an
instruction
from
the
ABSCM
.

AT
control
module
(TCM)
(AT
vehicles
only)
Provides
shift
controls
(fixing
the
speed
at
3rd
or
changing
front
and
rear
wheel
transmission
characteristics
on
4WD
vehicle)
in
response
to
an
instruction
fromthe
ABSCM
.

SERVICE
PROCEDURE
[W25D21
4-4

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

Diagnosis
connector
--J

1

I`

--~
~
''-
Diagnosis
terminals

3
terminal
6
terminal
-
/

B4M0082D
D
:
ABS
SEQUENCE
CONTROL

1)
Under
the
ABS
sequence
control,
after
thehydraulic

unit
solenoid
valve
is
driven,
theoperation
of
thehydrau-

lic
unit
can
be
checked
by
means
of
the
brake
tester
or

pressure
gauge
.

2)
ABS
sequence
control
can
be
started
by
diagnosis

connector
or
select
monitor
.

1
.
OPERATIONAL
GUIDELINES
OF
THE
ABS

SEQUENCE
CONTROL
WITH
DIAGNOSIS
CONNECTOR

1)
Connect
diagnosis
terminals
to
terminals
No
.
3
andNo
.

6
of
the
diagnosis
connector
beside
driver's
seat
heater

unit
.

2)
Setthe
speed
of
all
wheels
at
4
km/h
(2
MPH)
or
less
.

3)
Turn
ignition
switch
OFF
.

4)
Within
0
.5
seconds
after
the
ABS
warning
light
goes

out,
depress
the
brake
pedal
and
hold
it
immediately
after

ignition
switch
is
turned
to
ON
.

CAUTION
:

Do
not
depress
the
clutch
pedal
.

NOTE
:

*
When
the
ignition
switch
is
setto
on,the
brake
pedal

must
not
be
depressed
.

Engine
must
not
operate
.

5)
After
completion
of
ABS
sequence
control,
turn
ignition

switch
OFF
.

2
.
OPERATIONAL
GUIDELINES
OF
THE
ABS

SEQUENCE
CONTROL
WITH
SELECT
MONITOR

NOTE
:

In
the
event
of
any
trouble,
the
sequence
control
may
not

be
operative
.
In
such
a
case,
activate
the
sequence

control,
referring
to
"OPERATIONAL
GUIDELINES
OF
THE

ABS
SEQUENCE
CONTROL
WITHDIAGNOSIS
CONNEC-

TOR
"
.
<
Ref
.
to
4-4
[W25D1],*10>

1)
Connect
select
monitor
to
data
link
connector
beside

driver's
seat
heater
unit
.

2)
Turn
ignition
switch
ON
.

3)
Put
select
monitor
to
ABS
mode
.

11

SERVICE
PROCEDURE
[w2sDa1
4-4

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

AB
S
FUNCTION

CHECK
END

B4M1030

MODE
RESTART?

0
:
YE
S
1
:
NO

H4M
1144

10)
After
completion
of
ABS
sequence
control
.

11)
Press0key
tostart
ABS
sequence
control
again
and

press
1
key
to
end
.

3
.
CONDITIONS
FOR
COMPLETIONOF
ABS

SEQUENCE
CONTROL

When
the
following
conditions
develop,
the
ABS
sequence

control
stops
and
ABS
operation
is
returned
to
the
normal

control
mode
.

1)
When
the
speed
ofat
least
one
wheel
reaches
10
km/h

(6
MPH)
.

2)
When
terminal
No
.
3
or
No
.
6
are
separated
from
diag-

nosis
terminals
.
(When
select
monitor
is
not
used
.)

3)
When
the
brakepedal
is
released
during
sequence

control
and
the
braking
lamp
switch
is
set
to
off
.

4)
When
brake
pedal
is
depressed
afterignition
key
is

turned
to
ON,
and
before
ABS
warning
light
goes
out
.

(When
select
monitor
is
not
used
.)

5)
When
brakepedal
is
not
depressed
after
ignition
key

is
turned
to
ON,
acrd
within
0
.5
seconds
after
ABS
warn-

ing
light
goes
out
.
(When
select
monitor
is
not
used
.)

6)
After
completion
of
the
sequence
control
.

7)
When
malfunction
is
detected
.
(When
select
monitor
is

used
.)

13

4-4
[W25D4]
SERVICE
PROCEDURE

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

4
.
CONDITIONS
FORABS
SEQUENCE
CONTROL

4
km/h

Speed
of
all
wheels

HIGF
Terminal
No
.3
and
No
.6
LOV1
Operational
guide
lineofIgnition
key
switch
O
sequence
OFF

control
O
ABS
warning
light
OFF

HIGF
Stop
light
switch
LO"

HIGF
AT
ABS
signal
LOW

Valve
relay
ON

OFF

FL
outlet
valve
ON
OFF

FL
inlet
valve
O
NOFF

Operational
FR
outlet
valve
ON
OFF
pattern
of
ON
sequence
FR
inlet
valve
OFF
control
RR
outlet
valve
OFF
RR
inlet
valve
ON
OAF

RL
outlet
valve
OFF

RL
inlet
valve
ONOFF

Pump
motor
OFF

Operational
Pressure
of
master
cylinder

pressure
of
Pressure
of
FLwheel
cylinder
Pressure
of
FR
wheel
cylinder
sequence
Pressure
of
RR
wheel
cylinder
control
Pressure
of
RL
wheel
cylinder

Unit
:
second

B4M1001A
I

NOTE
:

*
When
select
monitor
is
used,
control
operation
starts
at

point
A
.
The
patterns
from
IGN
key
ON
to
the
point
A
show

that
operation
is
started
by
diagnosis
connector
.

HIGH
means
high
voltage
.

LOW
means
low
voltage
.

14

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
.

.
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

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

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

6
.
Diagnostics
Chart
for
On-board
Diagnosis
System

B
:
CHECK
LIST
FOR
INTERVIEW

Check
the
following
items
about
the
vehicle's
state
.

1
.
THE
STATE
OF
THE
ABS
WARNING
LIGHT

ABS
warning
light
O
Always

comes
on
.
D
Sometimes

O
Onlyonce

O
Does
not
come
on
o
When
/how
long
does
it
come
on?
:

Ignition
key
position
O
LOCK

D
ACC

OON
(before
starting
engine)

D
START

O
On
afterstarting
(Engine
is
running)

O
On
after
starting
(Engine
is
stop)

Timing
O
Immediately
afterignition
is
ON
.
O
Immediately
after
ignition
starts
.

O
When
advancing
km/h
to
km/h

MPH
to
MPH

D
While
traveling
at
a
constant
speed
km/h
MPH

D
When
decelerating
km/h
to
km/h

MPH
to
MPH
OWhen
turning
to
right
Steering
angle
:
deg

Steering
time
:
sec

D
When
turning
to
left
Steering
angle
:
deg

Steering
time
:
sec

D
When
moving
other
electrical
parts
Parts
name
Operating
condition

2
.
SYMPTOMS

ABS
operating
D
Performsno
work
.

condition
D
Operates
only
when
abruptly
applying
brakes
.
Vehicle
speed
:
km/h

MPH

~
How
to
step
on
brake
pedal

a)
Operating
time
:
sec

b)
Operating
noise
:
O
Produce
/
D
Does
not
produce

oWhat
kind
of
noise?
O
Knock

O
Gong
gong

D
Bong

a
Buzz

D
Gong
gong
buzz

O
Others

c)
Reaction
force
of
brake
pedal

O
Stick
O
Press
down
once
with
a
clunk

O
Press
and
released

D
Others

12