1997 SUBARU LEGACY brake sensor

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

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

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
`
"
...
.,`
@
.

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

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

4-4a
[TBAO1
BRAKES
[ABS
5
.31
TYPE]

8
.
Diagnostics
Chart
with
Trouble
Code
by
ABS
Warning
Light

8
.
Diagnostics
Chart
with
Trouble
Code

by
ABS
Warning
Light

A
:
LIST
OF
TROUBLE
CODE

Trouble
code
Contents
of
diagnosis
Ref
.
to
11

Start
code

e
Trouble
code
is
shown
afterstart
code
.

*
Only
start
code
is
shown
in
normal
condition
.

-

21
Front
right
ABS
sensor
[T8B0]*10

23
Abnormal
ABS
sensor
Front
left
ABS
sensor
[T8C0]*10

25
(Open
circuit
or
input
voltage
too
high)
Rear
right
ABS
sensor
[T8D0]*10

27
Rear
left
ABS
sensor
[T8E0]x10

22
Front
right
ABS
sensor
[T8F0]*10

24
Front
left
ABS
sensor
[T8G0]dr10

26
Abnormal
ABS
sensor

(Abnormal
ABS
sensor
signal)
Rear
right
ABS
sensor
[T8H0]*10

28
Rear
left
ABS
sensor
[T810]*10

29
Any
one
of
four
[T8J0]*10

31Front
rightinlet
valve
[T8K0]*10

32
Front
right
outlet
valve
[7800]*10

33
Front
left
inlet
valve
[TSLO]*10

34
Abnormal
solenoid
valve
circuit(s)
in
Front
left
outlet
valve
[T8PO]*10

35
ABS
control
module
and
hydraulic
unit
Rear
right
inlet
valve
[T8M0]*10

36Rear
right
outlet
valve
[T8QOj*10

37
Rear
left
inlet
valve
[T8N0]x10

38Rear
left
outlet
valve
[T8R0]*10

41
Abnormal
ABS
control
module
[T8SO1*10

42
Source
voltage
is
abnormal
.
[7870]*10

44
A
combination
of
AT
control
abnormal
[T8U0]t`r10

51
Abnormal
valve
relay
[T8V0]*10

52
Abnormal
motor
and/or
motor
relay
[T8W0]*10

54
Abnormal
stop
light
switch
(78X0]*10

56
Abnormal
G
sensor
output
voltage
[T8Y0)*10

30

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

8
.
Diagnostics
Chart
with
Trouble
Code
by
ABS
Warning
Light

B
:
TROUBLE
CODE
21
(FRONT
RH)

C
:
TROUBLE
CODE
23
(FRONT
LH)

D
:
TROUBLE
CODE
25
(REAR
RH)

E
:
TROUBLE
CODE
27
(REAR
LH)

-
ABNORMAL
ABS
SENSOR
(OPEN
CIRCUIT

OR
INPUT
VOLTAGE
TOO
HIGH)
-

DIAGNOSIS
:

"
Faulty
ABS
sensor
(Broken
wire,
input
voltage
too
high)

Faulty
harness
connector

TROUBLE
SYMPTOM
:

*
ABS
does
notoperate
.

WIRING
DIAGRAM
:

F49

ABS
control
module
and
hydraulic
control
unit

OUTBACK
with
steproof
model
B~5
O
O
P8
OO
Ft
100

1
3
1
10
70969
4
78

Rear
ABS
sensor
LH

RearABS
sensor
RH

r----------------
I
OUTBACK
with
steproof
model
I
I
Q
I

RearABS-C~l
sensor
LH

I
I

RearABS
j
~--m
sensor
RH

I
Q
I
------------J

Front
ABS
sensorLH

Front
ABS
sensor
RH

f{9

1
345678911112131415
1116
1
17
1
18
1
19
1
2
0
2
122
4
26
7
1
28
1
29
130131
1

B4M1238

32

BRAKES
[ABS
5
.31
TYPE]
[TSE2]4-4d

8
.
Diagnostics
Chart
with
Trouble
Code
by
ABS
Warning
Light

Except
OUTBACK
model

1
2

D

S2
B4MOSO6E

OUTBACK
model

Front
Rear

1
2
2
1

D

84M
1036C

Except
OUTBACK
model

1
2

-
L
Vq
f
1

B4MO807E

OUTBACK
model

Front
Rear

2
1

D

_v
B4M1037C

$E1
CHECK
ABS
SENSOR
.

1)
Turn
ignition
switch
to
OFF
.

2)
Disconnect
connector
from
ABS
sensor
.

3)
Measure
resistance
of
ABS
sensor
connector
terminals
.

Terminal

Front
RH
No
.
1
-
No
.
2
:

Front
LH
No
.
1
-
No
.
2
:

Rear
RH
No
.
1
-
No,
2
:

Rear
LHNo
.
1
-
No
.
2
:

CHECK
:
Is
the
resistance
between
0
.8
and
1
.2
kS2?

,rES
:
Go
to
step
8E2
.

No
:
Replace
ABS
sensor
.

8E2
I
CHECK
BATTERY
SHORT
OF
ABS
SENSOR
.

1)
Disconnect
connector
from
ABSCM&H1U
.

2)
Measure
voltage
between
ABS
sensor
and
chassis

ground
.

Terminal

Front
RH
No
.
1
(+)
-
Chassis
ground
(
)
:

Front
LH
No
.
1
(+)
-
Chassis
ground
(
)
:

Rear
RH
No
.
1
(
+)
-
Chassis
ground
(
)
:

Rear
LH
No
.
1
(+)
-
Chassis
ground
(
)
:

CHECK
:
Is
the
voltage
less
than
1
V?

vES
:
Go
to
step
8E3
.

No
:
Replace
ABS
sensor
.

33