1997 SUBARU LEGACY check engine light

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

BRAKES
[ABS
5
.31
TYPE]
IT8V3]4-4d

8
.
Diagnostics
Chad
with
Trouble
Codeby
ABS
Warning
Light

F49

1
1
213141516
1
7
1
89
101112131415
161718192
21
23
242526
728293031

D
n

SL
B4M1243A

00000
E3
[']C~oo
oooovoa
onoooo
.ooo~
"
oo

°~
1

IIII
`
84M1272A

18V-,
CHECK
INPUT
VOLTAGE
OF
ABSCM&H/U
.

1)
Turn
ignition
switch
to
OFF
.

2)
Disconnect
connector
from
ABSCM&H/U
.

3)
Run
the
engine
at
idle
.

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

chassis
ground
.

Connector
&
terminal

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

(F49)
No
.
24
(+)
-
Chassis
ground
(
)
:

CHEGK
:
Is
the
voltage
between
10
V
and
15
V?

YES
:
Go
to
step
8V2
.

No
:
Repair
harness
connector
between
battery
and

ABSCM&H/U
.

8V2
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
leis
than0
.5
0?

Go
to
step
8V3
.

No
:
Repair
ABSCM&H/U
ground
harness
.

8V3
CHECK
VALVE
.
RELAY
IN
ABSCM&H/U
.

Measure
resistance
between
ABS,CM&H/U
and
terminals
.

Terminals

No
.
23
(+)
-
-
No
.
24
(-)

CHECK
:
Is
theresistance
amore
than
1'
MSZ?

YES
:
Go
to
step
8V4
.

No
:
Replace
ABSCM&H/U
.

75