1997 SUBARU LEGACY check engine

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

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

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

BRAKES
[ABS
5
.31
TYPE]
[T7A3]
4-4d

7
.
Diagnostics
Chart
for
ABS
Warning
Light
Circuit
and
Diagnosis
Circuit
Failure

B1
2345
678910
1112
1
13
1
14
1
15
1
16
1
17
1
18
1
19
.
)

D

V

-
B4M1273A

I7A1
ICHONECK
IF
OTHER
WARNING
LIGHTS
TURN

Turn
ignition
switch
to
ON
(engine
OFF)
.

CHECK
:
Do
other
warning
lights
turn
on?

,rES
:
Go
to
step
7A2
.

No
:
Repair
combination
meter
.

7A2
I
CHECK
ABS
WARNING
LIGHT
BULB
.

1)
Turn
ignition
switch
to
OFF
.

2)
Remove
combination
meter
.

3)
Remove
ABS
warning
light
bulb
from
combination

meter
.

CHECK
:
Is
ABS
warning
light
bulb
OK?

,mss
:
Go
to
step
7A3
.

No
:
Replace
ABS
warning
light
bulb
.

7A3
CHECK
BATTERY

NG
LIGHT
HARNESS

SHO
RT
OF
ABS
WARN-

1)
Disconnect
connector
(B100)
from
connector
(F2)
.

2)
Measure
voltage
between
connector
(B100)
and
chas-

sis
ground
.

Connector
&
terminal
(B100)
No
.
9
(+)
-
Chassis
ground
(
)
:

CHECK
:
Is
thevoltage
less
than
3
V?

vES
:
Go
to
step
7A4
.

No
:
Repair
warning
light
harness
.

19

4-4d
[T7BaI
BRAKES
[ABS
5
.3i
TYPE]

7
.
Diagnostics
Chart
for
ABS
Warning
Light
Circuit
and
Diagnosis
Circuit
Failure

1~
\

MV

B4M0430

71134
CHECKGENERATOR
.

1)
Start
the
engine
.

2)
Idle
theengine
.

3)
Measure
voltage
between
generator
and
chassis

ground
.

Terminal

Generator
8
terminal
(+)
-
Chassis
ground
(
)
:

CHECK
;
Is
the
voltage
between
10
and
15
V?

vES
:
Go
to
step
7B5
.

No
:
Repair
generator
.

7B5
CHECK
BATTERY
TERMINAL
.

Turn
ignition
switch
to
OFF
.

CHECK
:
Is
there
poor
contact
at
battery
terminal?

,rES
:
Repair
battery
terminal
.

No
:
Go
to
step
7B6
.

71136
CHECK
POWER
SUPPLY
OF
ABSCM
.

1)
Disconnect
connector
from
ABSCM&H/U
.

2)
Start
engine
.

3)
Idle
the
engine
.

4)
Measure
voltage
between
ABSCM&H/U
connector
and

chassis
ground
.

Connector
&
terminal

(F49)
No
.
1
(+)
-
Chassis
ground
(-)
:

CHECK
:
Is
thevoltage
between
10
and
15
V?

ves
:
Go
to
step
71137
.

No
:
Repair
ABSCM&H/U
power
supply
circuit
.

71137
1
CHECK
WIRING
HARNESS
.

1)
Disconnect
connector
(F2)
from
connector
(B100)
.

2)
Turn
ignition
switch
to
ON
.

CHECK
:
Does
the
ABS
warning
light
remain
off?

S
:
Go
to
step
7B8
.

No
:
Repair
front
wiring
harness
.

26

BRAKES
[ABS
5
.31
TYPE]
IT8N3I4-4d

8
.
DiagnosticsChart
with
Trouble
Code
by
ABS
Warning
Light

819
11
Oil
111
21131141

4

161171181191212112
9
23
24
25
26
1
2
81
2
1301
31
1

F=_1

V
B4
M
1234A

F49

1
1
2
1
3
1
4
1
5
1
6
1
7
1
8
1
9
101112131415
11
16
1
17
1
18
1
19
1
2
01
212
23
24
25
26
L-~
7
1
28
1
2001
11

]L
COO
B4M
1243A

$N1
I
CHECK
INPUT
VOLTAGE
OF
ABSCM&H/U
.

1)
Disconnect
connector
from
ABSCM&H/U
.

2)
Run
theengine
at
idle
.

3)
Measure
voltage
between
ABSCM&H/U
connector
and

chassis
ground
.

Connector
&
terminal

(F49)
No
.
1
(+)
-
Chassis
ground
(-)
:

CHECK
;
Is
the
voltage
between
10
V
and
15
V?

,rES
:
Go
tostep
8N2
.

No
:
Repair
harness
connector
between
battery,
igni-

tion
switch
and
ABSCM&H/U
.

$N2
I
CHECK
GROUND
CIRCUIT
OF
ABSCM&H/U
.

1)
Turn
ignition
switch
to
OFF
.

2)
Measure
resistance
between
ABSCM&H/U
connector

and
chassis
ground
.

Connector
&
terminal

(F49)
No
.
23
-
Chassis
ground
:

CHECK
:
Is
the
resistance
less
than
0
.5
S2?

Go
to
step
8N3
.

No
:
Repair
ABSCM&H/U
ground
harness
.

$N3
I
CHECKPOOR
CONTACT
IN
CONNECTORS
.

Is
there
poor
contact
in
connectors
between

generator,
battery
and
ABSCM&HlU?
<
Ref
.

to
FOREWORD
[T3C1]
.*10
>

YES
:
Repair
connector
.

No
:
Go
to
step
8N4
.

55

BRAKES
[ABS
5
.31
TYPE]
[T8R3]
4-4d

8
.
Diagnostics
Chart
with
Trouble
Code
by
ABS
Warning
Light

F49

1
1
213
1
4
1
5
1
6
1
7
1
8
9
1
10
1
11
1
12
1
131
415
1
16
1
17
1
18
1
19
1
2
21
23
242526
728293031
1

D
~

]LB4M1243A

181111
1
CHECK
INPUT
VOLTAGEOF
ABSCM&H/U
.

1)
Disconnect
connector
from
ABSCM&H/U
.

2)
Run
the
engine
at
idle
.

3)
Measure
voltage
between
ABSCM&H/U
connector
and

chassis
ground
.

Connector
&
terminal

(F49)
No
.
1
(+)
-
Chassis
ground
(-)
:

CHECK
:
Is
thevoltage
between
10
V
and
15V?

,rES
:
Go
to
step
8112
.

No
:
Repair
harness
connector
between
battery,igni-
tion
switch
and
ABSCM&H/U
.

181112
CHECK
GROUND
CIRCUIT
OF
ABSCM&H/U
.

1)
Turn
ignition
switch
to
OFF
.

2)
Measure
resistance
between
ABSCM&H/U
connector

and
chassis
ground
.

Connector
&
terminal

(F49)
No
.
23
-
chassis
ground
:

CHECK
:
Is
the
resistance
less
than0
.5
S2?

Go
to
step
8R3
.

No
:
Repair
ABSCM&H/U
ground
harness
.

18113
1
CHECK
POOR
CONTACT
IN
CONNECTORS
.

Is
there
poor
contact
in
connectors
between

generator,
battery
and
ABSCM&HIU?
c
Ref
.

to
FOREWORD
[T3C1
]
.*10
>

,rES
:
Repair
connector
.

No
:
Go
to
step
8114
.

59

BRAKES
[ABS
5
.3i
TYPE]
[T8T3]
4-4Q

8
.
DiagnosticsChart
with
Trouble
Code
by
ABS
Warning
Light

\
7<
1

o

~
-
%mnn>>fl
5

B4M0430

F49

1
234
5
6
7
819
110111112113114115

4
1
18
22112
W23193123
1
24
1
25
1
26

L
F
a=--]

V

B4M1234A

18T1
I
CHECKGENERATOR
.

1)
Start
engine
.

2)
Idling
after
warm-up
.

3)
Measure
voltage
between
generator
B
terminal
and

chassis
ground
.

Terminal

Generator
B
terminal
-
Chassis
ground
:

CHECK
:
Is
thevoltage
between
10
V
and
17
V?

Go
to
step
8T2
.

No
:
Repair
generator
.

8T2
CHECK
BATTERY
TERMINAL
.

Turn
ignition
switch
to
OFF
.

CHECK
:
Are
the
positive
and
negative
battery
termi-

nals
tightly
clamped?

ves
:
Go
to
step
8T3
.

No
:
Tighten
the
clamp
of
terminal
.

8T3
CHECK
INPUT
VOLTAGE
OF
ABSCM&H/U
.

1)
Disconnect
connectorfrom
ABSCM&H/U
.

2)
Run
the
engine
at
idle
.

3)
Measure
voltage
between
ABSCM&H/U
connector
and

chassis
ground
.

Connector
&
terminal

(F49)
No
.
1
(+)
-
Chassis
ground
(
)
:

CHECK
:
Is
thevoltage
between
10
V
and
17
V?

YES
:
Go
to
step
8T4
.

No
:
Repair
harness
connector
between
battery,
igni-

tion
switch
and
ABSCM&H/U
.

67