1998 BMW M3 diff

5
.
Slowly
add
coolant
until
it
spills
from
bleed
screws
.

When
coolant
spillíng
from
bleed
screws
is
free
of
air

bubbies,
tighten
screws
.

6
.
Run
engine
until
it
reaches
operatíng
temperature
.
Af-

ter
engine
has
cooled,
recheck
coolant
level
and
top
up
as
necessary
.

CAUTION-

Always
use
genuine
BMW
coolant
or
its
equiva-

lent
to
avoid
the
formation
of
harmful,
clogging
de-

posits
in
the
cooling
system
.
Use
of
other
antifreeze
solutions
may
be
harmful
to
the
cooling
system
.

Tightening
Torque

"
Radiator
bleed
screw

to
thermostat
housing
...
.
.
........
8
Nm
(71
in-lb)

Belt-driven
cooling
fan,
replacing

1
.
Usinga32
mm
wrench
on
fan
clutch
nut,
turn
wrench

quickly
in
a
clockwise
direction
(working
from
front
of

car)
to
loosen
.
Spin
fan
off
pump
.
See
Fig
.
8
.

NOTE-

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

"
The
nut
may
be
difficult
to
loosen
.
Use
a
tool
to
hold
the
coolant
pump
pulleystationary
.
BMW
hasa
spe-
cial
tool
forthis
purpose
(BMW
special
tool
no
.
115
030)
.

2
.
Remove
expansion
rivets
holding
shroud
to
radiator
.

See
Fig
.
9
.
Remove
fan
and
shroud
together
.

NOTE-

Store
the
removed
fan
clutch
assembly
in
an
upright
(installed)
positionto
prevent
lossof
clutch
fluid
.

RADIATOR
AND
COOLING
SYSTEM



170-
7

Fig
.
8
.



Radiatorcooling
fannut
(arrow)
.
Nuthas
left-hand
threads
.

3
.
To
replace
fan
clutch,
remove
fan
mounting
bolts
and

separate
clutch
from
fan
.
Fig
.
9
.



Fan
shroud
retaining
rivet
(arrow)
.
Pryout
center
pin
and
re

4
.
Installation
is
reverse
of
rernoval
.



move
rivet
.
Rivet
design
may
vary
depending
on
model
and

model
year
.

Tightening
Torques

"
Clutchnut
to
coolant
pump
(left-hand
threads)

Wíthout
BMW
tool
no
.
11
5
040
.....
40
Nm
(29
ft-lb)

With
BMW
tool
no
.
11
5
040
.
......
30
Nm
(22
ft-Ib)

"
Fan
to
viscous
clutch
...
.
..
.
......
10
Nm
(89
in-lb)

0013203

COOLING
SYSTEM
SERVICE

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

13
.
Remove
transmission
mounting
bolts
(Torx-head)
.

Note
length
and
location
of
bolts
.
See
Fig
.
13
.

Fig
.
13
.
Transmission
mounting
bolts
.

0611642

CA
UTION-

Atno
time
should
the
weight
of
thetransmission
be
supported
by
the
transmission
inputshaft
.

NOTE
-

Washers
should
always
be
used
with
Torx-head
bolts
.

Installing
bolts
without
washers
will
make
them
difficult

to
loosen
.

MANUAL
TRANSMISSION



230-
7

Fig
.
14
.
Bellhousing
alignment
dowels
(arrows)
.

16
.
Install
driveshaft
and
preload
center
bearing
bracket
.

Usenew
nuts
when
mounting
driveshaft
to
transmis-

síon/flex
disc
and
final
drive
.
See
260
Driveshaft
.

17
.
Refill
transmission
with
appropriate
lubricant
before

starting
or
towingthe
car
.
See
Transmission
Fluid

Service
earlier
in
this
repair
group
.

14
.
Remove
transmission
by
pulling
backward
until
the
trans-



Tightening
Torques

mission
inputshaft
clears
the
clutch
disc
splines,
then



"
Reinforcing
cross
brace

pulí
downwards
.
Lower
jack
andremove
transmission
.



to
chassis
(M10)
.
...
.............
42
Nm
(31
ft-Ib)

"
Rubber
mount
to
transmission

15
.
Installation
is
reverse
of
removal,
keeping
in
mind
the



or
bracket
nut
(M8)
.
...
.
...
.......
21
Nm
(16
ft-Ib)

following
:



"
Slave
cylinder
to
transmission
......
22
Nm
(16
ft-Ib)

"
When
installing
exchange
transmission,
transfer
parts



"
Transmission
crossmember
to
chassis

from
old
unit
to
exchange
unit



M8
...............
.
.
...
..
22-24
Nm
(16-17
ft-Ib)

"
Thoroughly
clean
inputshaft
and
clutch
disc
splines
.



M10
..............
.
..
..
.......
42
Nm
(31
ft-Ib)

Lightly
lubrícate
transmission
inputshaft
before
in-



"
Transmission
to
engine
(Torx-head)

stalling
.-



M8
..
..................
..
.
..
..
22
Nm
(16
ft-Ib)

"
Be
sure
bellhousing
dowels
are
correctly
located
.
See



M10
.
.................
...
.
..
..
43
Nm
(32
ft-Ib)

Fig
.
14
.



M12
.
..................
..
.
..
..
72
Nm
(53
ft-Ib)

"
Center
rear
of
transmission
in
driveshaft
tunnel
before



"
Transmission
drain/fill
plugs
.
..
.
..
..
50
Nm
(37
ft-Ib)

tightening
transmission
support
bracket
.

TRANSMISSION
REMOVAL
AND
INSTALLATION

AUTOMATIC
TRANSMISSION



240-1

240
Automatic
Transmission

GENERAL
.....
.
.
.
.
.
.
.
.
.
.
.
.
.
.........
.
240-1



TRANSMISSION
REMOVAL
AND

INSTALLATION
..................
.
.
.
.
.240-4
TRANSMISSION
SERVICE
.
.
.
.
.
.......
.
240-1



Transmission,
removing
and
installing
....
.
.
.240-4

ATF
leve¡,
checking
..
.
.
.
.
.
.
.
.
.
..........
240-1

ATF,
draining
and
filling
.
.
.
.
.
.
.
..........
240-2



TABLE

a
.
Automatic
Transmission
Gear
Ratios
.......
..
.
.
240-1

GENERAL



TRANSMISSION
SERVICE



lo

Automatic
transmissions
are
identified
by
code
letters



ATF
leve¡,
checking

foundon
a
data
plate
located
on
the
sideof
thetransmission

case,
behind
the
manual
valve
lever
.
See
200Transmis-



The
automatic
transmissions
installed
in
the
E36
models
sion-General
for
application
information
.
Forgear
ratio
spec-



are
normally
filled
with
Dexron
III
automatic
transmission
fluid

ifications,
see
Table
a
.



(ATF),
although
alternative
fluids
have
been
installed
from
the

factory,
depending
on
transmission
type
and
model
year
.

CAUTION-



Some
transmíssions
are
filled
with
a
special
BMW
"lifetime"

ATF
does
not
circulate
unless
the
engine
is
run-



automatic
transmission
fluid,
which
does
not
require
periodic

ning
.
When
towing
an
automafic
transmission
ve-



fluid
changes
.

hicle,
usea
flat-bed
truck
or
ralse
the
rear
wheels
off
the
ground
.



CAUTION-

Mixing
different
types
of
transmission
fluids
will

The
electronic
transmission
control
module
(TCM)
monitors



lead
to
transmission
failure
.

transmissionoperation
for
faults
and
alerts
the
driver
by
illumi-

nating
the
transmission
fault
indicator
on
the
instrument
pan-

el
.
On-board
diagnostic
codes
stored
in
the
TCM
mustbe



NOTE-

downloaded
and
interpreted
by
trained
technicians
using
spe-



The
transmission
lubricant
instafed
can
be
foundona

cial
BMW
diagnostic
equipment
.



type
plate
on
the
side
of
the
transmission
.
In
addition,
a
sticker
may
be
located
on
the
fluid
sump
indicatingthe
typeof
transmission
lubricant
used
.
Ifin
doubt,
con

NOTE-



sult
an
authorized
BMW
dealer
for
altemate
fluid
use

Internal
repairs
to
the
automatic
transmission
require



and
current
information
regardingtransmission
operat-
special
service
equipment
and
knowledge
.
If
it
is
deter-



ing
fluids
.

mined
thatinterna¡
service
is
required,
consult
en
au-

thorízedBMWdealerabouta
factoryreconditioned
unit



The
transmission
is
not
equipped
with
a
dipstick
.
Checking
or
a
transmission
rebuild
.



the
ATF
leve¡
requires
measuring
and
maintaining
a
specified

ATF
temperature
during
the
checking
procedure
.
The
check-

ing
temperature
is
not
fully
warm
orcold
(the
ATF
sump

should
be
approximately
warm
to
the
touch)
.

Table
a
.
Automatic
Transmission
Gear
Ratios

Transmission



MS
310R
(THM-R1)



MS
310R
(THM-Rl)



MS
310Z(5HP
18)



I



MS
270R
(THM-R1)
(1992-1993)(1993-on)

Gear
ratios
:
1st



2
.40



2
.86



3
.67



2
.86

2nd



1
.47



1
.62



2
.00



1
.62
3rd



1
.00



1
.00



1.41



1
.00
4th



0
.72



0
.72



1
.00



0
.72
5th



-



-



0
.74



-
Reverse



2
.00



2
.00



4
.10



2
.00

TRANSMISSIONSERVICE

240-
6



AUTOMATIC
TRANSMISSION

14
.
Remove
transmission
by
pulling
back
and
down
.
Lower

jack
to
allow
transmission
to
clear
vehicle
.



Tightening
Torques

"
ATF
drain
plug
to
ATF
sump

CA
UTION-



MS
270R/A4S
310R
....
..
....
.
..
25
Nm
(18
ft-Ib)

Do
not
allow
the
torque
converter
to
fati
off
the



ASS
310Z(M10
plug)
..
..
..
.
.
..
.
..
16
Nm
(12
ft-Ib)

transmission
inputshaft
.



"
ATF
fill
plug
to
ATF
sump

MS
270R/A4S
310R
..
..
....
..
..
.
33
Nm
(24
ft-Ib)

15
.
Installation
is
reverse
of
removal,
noting
the
following
:



MS
310Z(M30
plug)
......
.
.
..
.
.
100
Nm
(74
ft-Ib)

"Blowoutofcoolerlineswithlow-pressurecompressed



"
ATF
cooler
lines
(A4S
270R/A4S
310R)

air
and
flush
coolerwith
clean
ATF
twice
before
reat-



Coupling
nuts
............
.
.
..
..
.
20
Nm
(15
ft-Ib)

taching
lines
to
transmission
.



Hollow
bolts
.........
.
.....
..
..
.
37
Nm
(28
ft-Ib)

"
Reinforcing
cross
brace

CAUTION-



to
chassis
(M10)
.............
.
..
.
42
Nm
(31
ft-Ib)

"
Wear
safety
glasses
when
working
with
com-



"
Torque
converter

pressedair
.



to
driveplate
(M10)
.........
..
.
..
45
Nm
(33
ft-Ib)

"
Transmissionsupport
crossmember
to
chassis

"
Do
not
reuse
ATF
after
flushing
.



M8
......................
22-24
Nm
(16-17
ft-1b)

M10
................
.
....
..
.
..
42
Nm
(31
ft-Ib)

"
Install
new
sealing
washers
on
hollow
bolts
.



"
Transmissíon
to
engine
(Torx-head
with
washer)

"
Insta¡¡
new
O-rings
on
transmission
cooler
lines,
where



M8
......................
..
.
..
21
Nm
(15
ft-Ib)

applicable
.



M10
.....................
..
..
.
42
Nm
(31
ft-Ib)

"
Inspect
driveplate
for
cracks
or
elongatedholes
.
Re-



M12
................
.
....
..
.
..
72
Nm
(53ft-Ib)

place
if
necessary
.

"
Check
to
be
sure
torque
converter
is
seated
correctly

in
transmission
during
final
installation
.

"
When
mounting
transmission
to
engine,
the
three

mounting
tabs
on
torque
converter
must
be
aligned

with
indentations
on
driveplate
.
Use
an
alignment

dowel
to
line
up
bolt
holes,
if
necessary
.
"
Fill
transmission
with
clean
ATF
until
oil
leve¡
is
even
with
fill
hole
.
Then
check
fluid
leve¡
as
described
ear-
lier
.

"
Adjust
gearshift
mechanism
.
See
250
Gearshift
link-

age
.

NOTE-

Torx-head
mounting
bolts
shouldalwaysbe
used
with
washers
to
prevent
difficult
removal
.

TRANSMISSION
REMOVAL
AND
INSTALLATION

DRIVESHAFT
SERVICE
.
...
.
.
.
...
.
..
.
.
.260-3

Driveshaft,
aligning
...............
.
...
.
.
260-3

Driveshaft,
removing
..............
.
.
.
.
.
.
260-4

260
Driveshaft

DRIVESHAFT
260-1

GENERAL
.
.
.
.
.
.
.
.....
.
.
.
........
.
...
.
260-1



Driveshaft,
installing
.
....
.
..
.
............
260-4

Flex-disc,
replacing
.....
.
.
.
.............
260-5
TROUBLESHOOTING
..
.
.
.
...
.
.........
260-1



Center
bearing
assembly,
replacing
.
......
.260-6
Frontcentering
guide,
replacing
..
.
.......
.
260-7

TABLE

a
.
Driveshaft
Troubleshooting
.
.
...
......
.
....
..
.
.
260-2

GENERAL



NOTE-

For
rear
drive
axlerepair
information,
see330
Rear
The
two-piece
driveshaft
is
joined
in
thecenter
by
a
sliding



Suspension
.
splined
coupling
.
This
coupling
compensates
for
fore
and
aft
movement
of
the
drive
line
.
The
driveshaft
ís
connected
to
the



Driveshaft
noise
or
vibration
may
be
caused
by
worn
or
transmission
bya
rubber
flex-disc
and
to
the
final
drive
by
a



damaged
components
.
Check
the
universal
joints
for
play
.
universal
joint
.
It
is
supported
in
the
micidle
by
a
center
support



With
the
driveshaft
installed,
pull
and
twist
the
driveshaft
while
bearing
.
The
bearing
is
mounted
in
rubber
to
isolate
vibration
.



watching
the
joint
.
The
BMW
specificationfor
play
is
very
See
Fig
.
1
.



small,
so
almost
any
noticeableplay
could
indicate
a
problem
.

TROU
BLESHOOTING



Check
thetorque
of
thefasteners
at
the
flange
connections
.
Check
therubber
of
the
flex-disc
and
center
bearing
for
dete

The
source
of
driveline
vibrations
and
noise
can
be
difficult



rioration
or
tearíng
and
check
for
preload
at
the
center
bearing

to
pinpoint
.
Engine,
transmission,
rear
axle,
or
wheel
vibra-



with
a
visual
inspection
.
Check
the
driveshaft
for
broken
or

tions
can
be
transmitted
through
the
driveshaft
to
the
car



missing
balance
weights
.
The
weights
are
welded
tabs
on
the

body
.
Noises
from
the
rear
of
thecar
may
be
caused
by
final



driveshaft
tubes
.
In
addition
to
inspecting
for
faulty
driveshaft

drive
problems,
orby
faulty
wheel
bearings,
drive
axies,
or



parts,
the
installed
angles
of
the
driveshaft
should
also
be

evenworn
or
improperly
inflatedtires
.



considered
.

Flex-disc

Center
universal
joint

Fig
.1
.



Driveshaft
and
final
drive
assembly
.

Rear
section
Splined
shaft



of
driveshaft
Center
support



`



Clamping
sleeve
bearíng
assembly

Differential
inputflange

0013110

TROUBLESHOOTING

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-

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