hydraulic BMW 325i 1993 E36 Owner's Manual

121-
6



BATTERY
STARTER,
ALTERNATOR

Alternator,
removing
and
installing

(6-cylinder
engine)

A
replacement
alternator
should
have
the
same
rating
as

the
original
.
Alternator
manufacturer
and
ampere
rating
are

normally
marked
on
the
alternator
housing
.

1
.
Disconnect
negative
(-)
battery
cable
.

CAUTION-

Prior
to
disconnectiog
the
battery,
read
the
battery
disconnection
cautions
given
at
the
front
of
this
manual
onpage
viii
.

2
.
Remove
alternator
cooling
duct
and
air
filter
housing

assembly
from
car
.
Disconnect
wiring
from
rear
of
alter-

nator
.

3
.
Remove
radiator
cooling
fan
and
fan
shroud
.
See
170

Radiator
and
Cooling
System
.

4
.
Remove
alternator
drive
belt
from
alternator
pulley
.
On

engines
with
hydraulic
belt
tensioner,
remove
tensioner

idler
pulley
(upper
roller)
from
alternator
bracket
.
See

Fig
.
5
.

ALTERNATOR
SERVICE

Fig
.
5
.



Pry
off
cover
from
tensioner
and
then
lever
tensioner
clock-
wise
to
release
belt
tension
.
Remove
upper
roller
(A)
once
belt
ís
removed
.

NOTE-

If
reusing
drive
belt,
mark
direction
of
rotation
on
belt

before
removing
.

5
.
Remove
upper
and
lower
mounting
bolts
and
lift
out
al-

ternator
.

6
.
Installation
is
reverse
of
removal
.
Note
locating
notches
on
tensioner
idler
pulley
(upper
roller)
alternator
brack-

et
when
installing
pulley
.

Tightening
Torques

"
D+
wire
to
alternator
(M6
nut)
.......
7
Nm
(53
in-lb)

"
B+
wireto
alternator
(M8
nut)
.......
13
Nm
(10
ft-Ib)

"
Pulley
to
alternator
(M16
nut)
.......
60
Nm
(44
ft-Ib)

Voltage
regulator,
removing
and
installing

1
.
Disconnect
negative
(-)
cable
from
battery
.

NOTE-



2
.
Remove
alternator
as
described
earlier
.

The
radiator
cooling
fan
nut
(32
mm
wrench)has
left-
hand
threads
.



3
.
Remove
cooling
duct
from
rear
of
alternator
.
See
Fig
.
6
.

Alternator

.
.g-



p~
J

-..
.

Fig
.
6
.



Alternator
assemblyand
related
parts
.

Cooling
duct

0012524

4
.
Remove
voltage
regulator
mounting
screws
and
re-

move
regulator
from
alternator
.

5
.
Installation
is
reverse
of
removal
.
Clean
brush
contact

surfaces
in
alternator
and
check
brush
length
asde-

scribed
later
.

GENERAL
..
.
......
.
.
.
.....
.
...
.
.
.
.
.
.
.
.
200-1

Manual
Transmission
.
.
.....
.
.
.
.'
.
.
.
.
.
.
.
.
200-1

Automatic
Transmission
.........
.
.
.
.
.
.
.
.
200-1

Transmission
ID
Codes
..........
.
.
.
.
.
.
.
.
200-2

GENERAL

E36
models
areequipped
with
a
longitudinal
drivetrain
.
The

transmission
is
bolted
directly
to
the
rear
of
the
engine
.
A

driveshaft
connects
the
output
shaft
of
thetransmission
to
the

final
drive
.
The
final
drive
is
mounted
lo
the
rear
suspension

and
the
body
.
Individual
drive
axles
with
integrated
constant

velocity
joints
transfer
rotational
power
to
the
rear
wheels
.

Manual
Transmission

Due
to
different
power
characteristics
and
performance
re-

quirements,
four
different
manual
transmissions
are
used
in

the
models
coveredby
this
manual
.
Manual
transmission
ap-

plications
are
given
in
Table
a
.

TRANSMISSION-GENERAL
200-1

200
Transmission-General

TABLES

a
.
Manual
Transmission
Applications
..
...........
200-1
b
.
Automatic
Transmission
Applications
...........
200-1

Fig
.
1
.



ZF-manufacturedmanual
transmission
.

For
transmission
gear
ratio
information
and
repair
informa-

tion,
see
230
Manual
Transmission
.



Automatic
Transmission

E36
carswith
standard
transmission
use
a
single-disc
clutch
with
dual-mass
flywheel
.
For
further
information,
see
210
Clutch
.

Table
a
.
Manual
Transmission
Applications

Model
Year
Engine
Transmission
318ifisfC



1992-1995



M42



Getrag
S5D
200
G'

1996-1998



M44



Getrag
S5D
250
G

323is/iC



1998



M52



Getrag
S5D
250
G

325ifsriC



1992-1995



M50



Getrag
S5D
250
G

3281/isfC



1996-1998



M52



ZF
S5D320
Z

M3



1995



S50US



ZF
S5D310
Z

1996-1998



S52US



ZF
S5D320
Z

'The
1992
M42
engine
may
be
fitted
witheither
the
Getrag
SSD
200
G
trans-
mission
or
S5D
250
Getrag
.
The
S5D
200G
was
discontinued
in
production
in
as
of
9/92
.
Thistransmission
is
interchangeable
with
Getrag
S5D
250
G
.

Four
different
automatic
transmissions
are
used,
depend-

ing
on
model
and
model
year
and/or
production
date
.
All
of
the

automatic
transmissions
are
electrohydraulically
controlled

with
either
four
or
five
forward
speeds
.
Automatic
transmis-

sion
applications
are
given
in
Table
b
.

For
automatic
transmission
repair
information,
see
240Au-

tomatic
Transmission
.

Table
b
.
Automatic
Transmission
Applications

Model
1
Year
1
Engine
1
Transmission

318i1is/1C



1992-1995
~
M42
323isfiC



1998



M52



A4S
310
R
3251/is/1C
1992-1995
M50

3181/isfC



11996-1998



M44



A4S
270
R
328i/is/1C
1996-1998
M52

M3



1996-1998



S50US



I
A5S
310
Z
S52US

GENERAL

GENERAL
..
.
.
.
.
.
.
.
.
.
.
.
.
.
......
.
......
210-1



CLUTCH
MECHANICAL
.
.
.
.
.
...
.
.....
.
.
210-3

CLUTCH
HYDRAULICS
.
.
.
.............
210-1



Clutch,
removing
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
...
.
.
.
.
210-4

Clutch,inspecting
and
installing
.
.
.
.
.
.
.
.
.
.
.
.210-5Clutch
hydraulic
system,



Transmission
pilot
bearing,replacing
.
.
.
.
...
210-6
bleeding
and
flushing
.
.
.
.
.
.......
.
.....
210-2

Clutch
master
cylinder,
replacing
..
.
.
.
.
.
...
210-2



Table

Clutch
slave
cylinder,
replacing
...
.
.
.
.
.
.
.
.
210-3



a
.
Clutch
Disc
Diameter
.............
..
..
.
......
210-3

GENERAL



CLUTCH
HYDRAULICS

This
repair
group
covers
replacement
of
the
clutch
mechan-



The
Clutch
is
hydraulically
actuated
by
the
master
and
slave
¡cal
and
hydraulic
components
.
Special
tools
may
be
required



cylinders
.
Clutch
disc
wear
is
automatically
taken
upby
the
for
some
of
the
procedures
.
Read
the
procedure
through
be-



pushrod
travelof
the
slave
cylinder,
making
periodic
adjust-fore
beginning
a
job
.



ments
unnecessary
.

NOTE-

See200
Transmission-General
for
transmission
applicatíon
information
.

The
major
components
of
the
clutch
system
are
shown
in

Fig
.
1
.

Engine



Pressure
plate

flywheel,,
assembly

Clutch

Flywheel
bolt

Pressure
plate
release
lever



Release
lever

Fig
.
1
.



Clutch
assembly
and
hydraufcs
.

210
Clutch

Release
bearing

Pushrod

A
soft
or
spongy
feel
to
the
clutchpedal,
long
pedal
free-
play,
or
grinding
noises
from
thegears
while
shifting
can
all
in-
dicate
problems
with
the
Clutch
hydraulics
.
In
these
circum-
stances
it
is
best
to
start
with
a
clutch
fluid
flush,
followed,
if

necessary,
byreplacement
of
the
hydraulic
parts
.

From
brake
fluid
reservoir

CLUTCH
210-1

0

0

Transmission
inputshaft

Clutch
master
cylinder

Bulkhead

Slave
cylinder
6535

CLUTCH
HYDRAULICS

210-2
CLUTCH

Clutch
hydraulic
system,

bleeding
and
flushing

If
the
clutch/brake
fluid
is
murky
or
muddy,
or
has
not
been

changed
within
the
last
two
years,
the
system
should
be

flushed
.
Flushing
the
old
fluid
from
the
clutch
lines
is
done
us-

ing
a
brake
system
pressure
bleeder
.

1
.
Remove
brake
fluíd
reservoir
cap
.
Usinga
clean
sy-

ringe,
remove
brake
fluid
from
reservoir
.
Refill
reservoir

with
clean
fluid
.

2
.
Attach
pressure
brake
bleeder
to
fluid
reservoír
.

CA
UTION-

Do
not
exceed
2
bar
(29
psi)
pressure
at
the
fluid
reservoir
when
bleeding
or
flushing
the
hydraulic
system
.

3
.
Connect
a
length
of
hose
from
clutch
slave
cylinder

bleeder
valve
lo
a
container
.
See
Fig
.
2
.

0012003
Fig
.
2
.



Clutch
slave
cylinder
bleeder
valve
on
left
side
of
transmission
(arrow)
.

4
.
Open
bleeder
valve
and
allow
brake
fluid
to
expel
until
clean
fluid
comes
out
free
of
air
bubbles
.

5
.
Close
bleeder
valve
and
disconnect
pressure
bleeding
equipment
from
fluid
reservoir
.
Hose
on
bleeder
valve
remainsconnected
.

6
.
Slowly
operate
clutch
pedal
about10
times
.
Fill
reser-
voir
with
clean
fluid
asnecessary
.

7
.
Unbolt
slavecylinder
from
transmission
.

8
.
Position
slave
cylinder
so
that
bleeder
valve
is
facing
up
(highest
point)
.

CLUTCH
HYDRAULICS

9
.
Open
bleeder
valve
and
slowly
push
slave
cylinder

pushrod
al¡
the
way
in
.
Close
bleeder
valve
and
slowly

release
pushrod
.
Repeat
procedure
until
fluid
runs
out

clear
and
without
bubbles
.

10
.
Disconnect
bleeder
hose
.
Instan
slavecylinder
lo
trans-

mission
.
Add
cleanbrake
fluid
to
reservoir
as
neces-

sary
.
Check
clutch
operation
.

Tightening
Torques

"
Clutch
slave
cylinder
to
transmission
................
..
22
Nm
(17
ft
lb)

Clutch
master
cylinder,
replacing

The
clutch
master
cylinder
is
mounted
to
the
pedal
assem-

bly,
directly
above
the
clutch
pedal
.
1
.
Disconnect
negative
(-)
cable
from
battery
.

CAUTION-

Prior
to
disconnectiog
the
battery,
read
the
battery
disconnection
cautionsgiven
at
the
front
of
this
manual
on
page
viii
.

2
.
Remove
brake
fluid
reservoir
cap
.
Usinga
clean
sy-

ringe,
remove
brake
fluid
from
reservoir
.

CA
UTION-

Brake
fluid
is
poisonous,
highly
corrosive
and
dan-gerous
to
the
environment
.
Wear
safety
glasses
and
rubbergloves
when
working
with
brake
fluid
.
Do
notsiphonbrake
fluid
with
your
mouth
.
Imme-
diately
clean
away
any
fluid
spilled
on
painted
sur-
faces
and
wash
with
water,
asbrake
fluid
will
remove
point
.

3
.
Disconnect
fluid
supply
hose
from
master
cylinder
.

Placea
pan
under
hose
to
catch
any
excess
fluid
.

4
.
Working
in
engine
compartment,
disconnect
fluid
line
fitting
frommaster
cylinder
.

5
.
Working
in
passenger
compartment,
remove
lower
in-
strument
panel
trim
above
pedal
cluster
.

6
.
Disconnect
clutch
pedal
from
clutch
master
cylinder
push
rod
by
removing
clevis
pin
locking
clip
and
slide
out
clevis
pin
.

7
.
Remove
master
cylinder
mounting
bolts
.
See
Fig
.
3
.

8
.
Installation
is
reverse
of
removal
.
Fill
fluid
reservoir
with
clean
fluid
.
Bleed
clutch
hydraulics
as
described
earlier
.

Connect
negative
cable
to
battery
last
.

Fig
.
3
.



Clutch
master
cylinder
mounting
bolts
.

Clutch
slave
cylinder,
replacing

0012589

Tightening
Torques

"
Clutch
master
cylinder
to
bulkhead
..
22
Nm
(17
ft-Ib)
"
Fluid
line
to
master
cylinder

orslave
cylinder
.................
16
Nm
(12
ft-1b)

The
clutch
slave
cylinder
is
mounted
on
the
left
side
of
the

transmission
.



CLUTCH
MECHANICAL

1
.
Remove
brake
fluid
reservoir
cap
.
Using
a
clean
sy-

ringe,
remove
brake
fluid
from
reservoir
.

2
.
Disconnect
fluid
hose
from
slave
cylinder
.
Place
a
pan

under
hose
to
catch
any
excess
fluid
.

3
.
Unbolt
slave
cylinder
from
transmission
.
See
Fig
.
4
.

4
.
Installation
is
reverse
of
removal,
noting
the
following
:

"
Check
for
wear
on
pushrod
.
Any
other
wear
except
on

tipis
caused
by
misalignment
of
clutch
components
.

"
Lightly
coat
pushrod
tip
with
molybdenum
disulfide

grease
(Molykote
0
Longterm
2
or
equivalent)
.

"
During
installation
be
sure
pushrod
tip
engages
recess

in
clutch
release
lever
.

"
Fill
fluid
reservoir
with
clean
fluid
.

"
Bleed
clutch
hydraulics
as
described
earlier
.

CLUTCH
210-
3

Fig
.
4
.



Clutch
slave
cylinder
mounting
bolts
(arrows)
.

Tablea
.
ClutchDisc
Diameter

Model



Diameter

3181/is/iC



215
mm
(8
.46
in)

325i/is/iC



228
mm
(8
.98
in)
323is/iC

328i/is/iC



240
mm
(9
.45
in)
M3

0012715

Tightening
Torques

"
Clutch
slave
cylinder

to
transmission
.
.
................
22
Nm
(17
ft
lb)
"
Fluid
line
to
slave
cylinder
......
.17
Nm
(10-12
ft
lb)

The
transmission
must
be
removed
from
the
engine
to
ac-

cess
the
clutch
mechanical
components
.
It
is
recommended

that
the
clutch
disc,
pressure
plate
and
release
bearing
be
re-

placed
duringa
clutch
overhaul
.
Be
sure
to
check
the
bottom

of
the
bellhousing
for
oil
.
If
engine
oil
is
found,
check
for
a

faulty
rear
crankshaft
oil
seal
.

CLUTCH
MECHANICAL

300-2



SUSPENSION,
STEERING
AND
BRAKES-GENERAL

Steering

INTEGRATED
SYSTEMS

The
steering
linkage
connects
the
rack-and-pinion
unit
through
tie
rodsto
the
steering
arms
.
The
tie
rod
ends
allow
the
wheels
to
pivot
and
react
to
suspension
travel
.

Rear
Suspension

The
rear
axle
carrier
is
the
main
mounting
point
for
the
final

drive
housing
and
the
rear
suspension
components
.

Trailing
arms
locatethe
rear
wheels
and
anchorthe
springs,

shocks
and
stabilizer
bar
.
Driveaxies
with
constant-velocity

(CV)
joints
at
both
ends
transfer
power
from
the
differential
to

the
road
wheels
.
The
differential
is
mounted
to
the
rearaxle

carrier
through
rubber
mountsand
bushings
to
hele
isolate

drivetrain
noise
and
vibration
.

Brakes

E36
cars
areequipped
with
power
disc
brakes
with
an
inte-
gral
antilock
brakes
(ABS)
.
The
parking
brake
is
a
dual-drum

system
integrated
with
the
rear
brake
rotors
.
See
Fig
.
3
.

Power
assist
is
provided
by
a
vacuum
booster
when
the
en-

gine
is
running
.
The
brakepedal
pushrod
is
connected
directly

to
the
master
cylinder,
so
failure
of
the
vacuum
booster
does

not
normally
result
in
total
brake
failure
.

0012124



Each
disc
brakeuses
a
caliper
with
a
single
hydraulic
cylin-
Fig
.
2
.



Front
suspension
control
arm
(arrow)
.



der
.
Brake
pads
in
the
left
front
and
right
rear
contain
wear

sensors
.
When
the
padsneed
replacement,the
sensors
illu-
The
front
suspension
is
designed
with
minimum
positive



minate
a
light
on
the
dashboard
.
steering
offset
.
This
geometry
contributes
to
stability
when

traction
is
unequalfrom
side
to
side
.
Suspension
travel
is
lim-



Tires
and
Wheels
ited
by
rubber
bump
stops
.

The
three
point
mounting
of
each
L-shaped
control
arm
ere-



Tiresize
is
critica¡
to
the
proper
operatíon
of
the
E36
ABS
or

cisely
controls
the
front-to-rear
and
side-to-side
position
of
the



ABS/AST
system
.
Severa¡
different
styles
of
wheels,
in
15,16

strut,
while
the
flexibility
of
the
joints
and
mounts
alsoallows



and
17
inch
diameters,
are
available
from
an
authorized
BMW

the
movement
necessary
for
suspension
travel
.
The
control



dealer
.

arm
mounting
points
are
designed
with
anti-dive
geometry
.

The
suspension
reduces
the
normaltendency
for
the
front
of



NOTE-
the
vehicle
to
dive
under
hard
braking
.



Aftermarket
wheelsshould
be
selected
wlth
care
.
Im-
properly
fitted
wheels
can
contact
anddamage
sus

Control
arm
position
is
fixed,
with
no
adjustment
provisions



pension,
brakeorbodycomponentsandmayadversely

on
the
control
arms
for
alter¡ng
front
wheel
al
ignment
.
A
stabi-



affect
vehicle
stability
.

lizer
bar
mounted
to
both
control
arms
heles
to
reduce
body
rol¡
whencomering
.



INTEGRATED
SYSTEMS

Antilock
Brake
System
(ABS)
is
standard
on
all
E36
cars
.

The
variable-assist
power
steering
system
consists
of
an



Standard
on
some
models
and
installed
as
optional
equipment
on

engine-driven
hydraulic
pump,
a
rack-and-pinion
type
steer-



others,
is
All
Season
Traction
(AST)
.

ing
gear,
and
connecting
linkage
to
the
road
wheels
.
TheE36
utilizes
an
engine-speed
dependent
variable
effort
steering



Antilock
Brake
System
(ABS)

system
.
At
low
speeds,
maximum
power
assist
is
provided
to
ease
parking
and
city
driving
.
Athigh
speeds,
assist
is
re-



The
electronically-controlled
ABS
maintains
vehícle
stabili
duced
to
ensure
stability
.



ty
and
control
during
emergency
braking
by
preventing
wheel
lock-up
.
ABS
provides
optimum
deceleration
and
stability
dur-

Wheel
brake
caliper

Electronic
control
module
Fig
.
4
.



Schematic
representation
of
ABS
.

SUSPENSION,
STEERING
ANDBRAKES-GENERAL



300-3

Fig
.
3
.



Schematic
view
ofdual
circuit
brakes
with
4-channel
ABS
.

ing
adverse
conditions
.
It
automatically
adjusts
brake
system
hydraulic
pressure
at
each
wheel
to
prevent
wheel
lock-up
.

The
system's
main
components
arethe
wheel
speed
(pulse)
sensors,
the
ABS
control
module,
and
the
hydraulic

control
unit
.
See
Fig
.
4
.

Warning
lamp

u
Master

Whee

_

l
speed



I-lydraulic



cylinder

sensor



control
unit



0012135

UNI

The
wheel
speed
sensors
continuously
send
wheel
speed
signals
to
the
control
module
.
See
Fig
.
5
.
The
control
module
compares
these
signals
to
determine,
in
fractions
of
a
second,
whether
any
of
the
wheels
areabout
to
lock
.
If
any
wheel
is
nearing
a
lock-up
condition,
the
module
signals
the
hydraulic
unit
to
maintain
or
reduce
pressure
at
the
appropriatewheel(s)
.
Pressure
is
modulated
by
electrically-operated
sole-

noid
valves
in
the
hydraulic
unit
.

Fig
.
5
.



ABS
wheelspeed
sensor
.

0006563

INTEGRATED
SYSTEMS

300-4



SUSPENSION,
STEERING
AND
BRAKES-GENERAL

Three-channel
ABS
ís
used
on
al[
E36
cars
equipped
with



Al¡
Season
Traction
(AST)
standard
ABS
.
Each
front
wheelhas
a
separate
solenoid

valve
to
modulate
hydraulic
pressure
to
that
brake
caliper
.



The
traction
control
system
works
in
conjunction
with
ABS
The
rear
wheels
are
modulated
asa
pair,
controlled
by
a
sin-



and
the
engine
management
system
to
enhance
vehicle
con
gle
solenoid
valve
.



trol
.
The
main
function
of
the
AST
system
is
to
maintain
the
rolling

contact
between
the
tires
and
the
road
surface
under
al¡
driving
E36
cars
equipped
with
ABS/AST
utilize
a
four
channel
sys-



conditions
.
This
is
achieved
through
exact
application
and
tem,
which
functionsexactly
as
the
three
channelsystem



management
of
braking
and
drivetrain
forces
.
above,except
that
the
rear
wheels
are
modulated
individually
.

IDLE
SPEED
CONTROL
VALVE

HROTTLE
PLATE

6
.

Í
III

i



ADS
ACTU
AT
OR

THROTTLE
PLATE
POSITION
SENSOR

DME

Fig
.
6
.
All
Season
Traction
(AS)
works
withother
drivetrain
systems
to
enhance
vehicle
control
.

INTEGRATED
SYSTEMS

The
throttle
control
system
used
in
AST
is
illustrated
in
Fig
.

MASS
AIR
FLOW
SENSOR

JADS
THROTTLE
PLATE
POSITION
SENSOR

0013006

NOTE-

The
traction
control
system
referred
to
as
AST
(all
sea-
son
traction)
may
also
be
referred
to
as
ASC
(Automat-
ic
Stability
Control)
and
ASC+T
(Automatic
Stability
Control+Traction)
.

The
AST
system
improves
traction
by
electronically
apply-

ing
the
rear
brakes
when
therear
drive
wheels
are
spinning
at

a
faster
rate
than
the
front
wheels
.
The
combined
ABS/AST

control
module,
operating
through
the
ABS
hydraulic
control

unit,
modulates
braking
force
at
therear
wheels
.

In
addition,
AST
uses
retarded
ignition
timing
and
an
auxil-iary
engine
throttle
plate
to
reduceengine
torque
and
maintain

vehicle
stability
.

The
auxiliary
throttle
plate
is
held
open
by
spring
pressure
.

The
AST
system
actívates
the
auxiliary
throttie
position
motor

(ADS)
to
cose
the
AST
throttle
as
needed
.
This
reduces
the

volume
of
engine
intake
air
.
Due
to
the
throttle
closing
very
rapidly
during
AST
operationthe
driver
cannot
increase
theengine
power
output
regardless
of
how
far
theaccelerator
pedal
is
pushed
to
the
floor
.

The
auxiliary
throttle
plate
is
placed
ahead
of
the
conven-

tional
throttle
plate
in
the
throttle
body
.

Traction
control
also
comes
into
operationduringdecelera-
tion
.
Decelerating
on
snowy
or
icy
road
surfaces
can
lead
to
rear
wheel
slip
.
If
a
rear
wheel
startsto
drag
or
lock
up
when

the
throttle
is
closed
rapidly
orduringdownshifting,the
AST
system
can
limit
the
problem
by
advancing
the
ignition
timing
.

A
switch
on
the
center
console
is
used
to
togglethe
AST
on

or
off
.

The
AST
system
is
designed
to
be
maintenance
free
.
There

are
no
adjustments
that
can
be
made
.
Repair
and
trouble-
shooting
of
the
AST
system
requires
special
test
equipment

andknowledgeand
should
be
performed
only
by
an
autho-

rized
BMW
dealer
.
Table
a
lists
theconditions
indicated
by

the
AST
indicator
light
in
the
instrument
cluster

SUSPENSION,
STEERING
AND
BRAKES-GENERAL



300-5

Tablea
.
AST
Indicator
Lamp
Function

Indicator
lamp



1
Condition



1
Comment

Light
on



Normal
AST
start-



Automatic
AST
up



self-test

Light
off



AST
monitoring



Automatic
AST
op-
mode



eration

Press
AST
button,



AST
off
(disabled)



Rocking
the
car
tolight
comes
on



getout
of
snow
or
other
loose
surface
Driving
with
snow
chains

Press
AST
button
:



AST
monitoring



Automatic
AST
op-
light
goes
out



I
mode



eration

Light
flashes



AST
active
mode



I
Normal
AST
oper-
ation
as
it
controls
wheel
speed

Light
stays
on
af-



Defect
in
AST



Consult
BMW
ter
start
up
or



dealer
for
diagno-
comes
on
while



sis/repair
driving



(Vehicle
operation
remains
normal)

WARNING
-

Even
a
car
with
AST
is
subject
to
the
normal
physi-
cal
laws
.
Avoid
excessive
speeds
for
the
road
con-
ditions
encountered
.

CAUTION-
"
If
the
tires
on
the
carare
of
different
makes,
the
AST
system
may
over-react
.
Only
fit
tires
of
the
same
make
and
tread
pattem,

"In
adverse
conditions,
such
as
trying
to
rock
the
car
outof
deep
snow
or
another
soft
surface,
or
when
snow
chainsare
fitted,
it
is
advisable
to
switch
off
AST
and
allow
the
cars
driveline
to
op-
erate
conventionally
.

INTEGRATED
SYSTEMS

300-6



SUSPENSION,
STEERING
AND
BRAKES-GENERAL

BATTE
RY

KL
30

ECM
MAIN
C~
RELAY



KL
15

DSC
SWITCH

LF1
;1~lZZ~



nSLn

l'
z
sJ



WHEEL

RF

c_
.

LR

r_
.
>
RR

ELECTRONIC
BRAKE
LIGHT
SWITCH

SPEED

SENSORS

Fig
.
7
.



Schematic
of
AII
Season
Traction
(AST)
system
.

INTEGRATED
SYSTEMS

EDC

POWER
SUPPLY



SOLENOID
RELAY
GROUND
CONTROL

POWER
SUPPLY
I'
1
ABS
PUMP

GROUND
CONTROLÍ
F



f
iJ
RELAY

INLET
(4X)
wxxuw
OUTLET
(4X)



-=-=--



AST
AST
INTAKE
IHYDRAULIC
-
=-

SWITCHING
=---

!
99001
!J

WHEEL
SPEED
X
4

DME
II

000001
-
f



1
UNIT

AGS

IKE
&
DMEI
PARK
BREVE

771
SWITCH

M
ALTERNATOR



AUXILIARY
THROTTLE

r
`



INDICATOR



POSITION
MOTOR
(ADS)

ABSPUMP



DIAGNOSIS

RELAY



lu~~~b

0013027