721
Airbag
System
(SRS)
Airbag
Systems
.......
.
...
.
.
.
.
.
....
.
.
.
.
721-1
AIRBAG
SENSORS
AND
ELECTRONICS
721-2
SRS
Warning
Light
and
Fault
Display
.
.
.
.
.
..
721-2
Airbagcontact
ring,
replacing
........
.
.
.
.
.
721-3
Airbag
crash
sensor,replacing
..
.
....
.
...
.
721-4
ZAE
control
module,
replacing
.
.
.
.........
721-5
GENERAL
This
repair
group
covers
only
removal
and
installation
of
air-
bag
components
.
Airbag
system
repair
and
fault
diagnosis
is
not
covered
here
.
Diagnostics,
component
testing,
and
airbag
system
repair
should
be
carried
out
by
trained
BMW
service
technicians
.
NOTE-
Special
test
equipment
is
required
to
retrieve
SRS
fault
codes,
diagnose
system
faults,
and
resetltum
off
the
SRS
indicator
light
.
The
SRS
indicator
light
will
remain
on
until
any
problem
has
been
corrected
and
the
fault
memory
has
been
cleared
.
When
servicing
cars
equipped
with
SRS,
the
precautions
on
this
page
mustbeobserved
to
prevent
personal
injury
.
Airbag
Systems
The
airbag
system
installed
on
E36
cars
through
the
1993
model
year
consisted
of
a
single
airbag
in
the
steering
wheel
.
This
systemcan
be
identified
by
the
orange
crash
sensors
lo-
cated
on
the
front
wheel
wells
and
the
absence
of
a
passenger
side
airbag
.
The
ZAE
airbag
system,
starting
in
model
year
1994
(pro-
duction
date9/93
and
later),
provides
both
a
driver
side
and
a
passenger
sideairbag
.
On
ZAE
vehicles,
the
crash
sensorsare
integrated
into
the
airbag
control
module,
located
under
thecenter
of
the
rear
seat
.
The
ZAE
control
module
triggers
deployment
of
the
airbags
When
it
sensos
the
vehicle
deceler-
ating
at
a
rate
equivalent
to
a
head-on
collisionof
at
least
13
mph
(18
km/h)
.
In
some
1997
4-door
models
and
all
1998
models,
side-impact
airbags
were
installed
in
the
front
doors
.
The
airbag
units
are
mounted
behindthe
door
trim
panels
.
Caution
mustbeused
when
working
on
vehicle
systems
in
the
proximity
of
air
bags,
such
as
the
steering
column,
the
dashboard,
or
the
doors
.
AIRBAG
SYSTEM
(SRS)
721-1
GENERAL
.
.
.
.
.
.
.
.
.
.
.......
.
......
.
.
.
.
721-1
Front
side-impact
airbag
crash
sensor,
removing
and
installing
....
.
.....
.
.....
.
721-5
AIRBAGS
..............
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
721-5
Driver
side
airbag,
removing
and
installing
.
.
.
721-5
Passenger
side
airbag,
removing
and
installing
..............
.
.
.721-6
Front
side-impact
airbag,
removing
and
installing
.
.
.
.
.
.
.
.
.
.
......
.721-7
WARNING
-
"
Airbag(s)
are
inflated
byan
explosive
device
.
Handled
improperly
or
without
adequate
safe-
guards,
the
System
can
be
very
dangerous
.
Spe-
cial
precautions
must
be
observed
prior
to
any
work
ator
near
the
driverside
airbag,
the
passen-
ger
side
airbag
(where
applicable)
or
the
side-im-
pact
airbags
(where
applicable)
.
"
The
airbag
is
a
vehicle
safety
system
.
Serious
in-
jury
may
result
if
System
service
is
attempted
by
persons
unfamiliar
with
the
BMW
SRS
and
its
ap-
proved
service
procedures
.
BMW
advises
that
all
inspection
and
service
be
performed
by
an
autho-
rized
BMW
dealer
.
"
Always
disconnect
the
battery
and
cover
the
neg-
ative
()
battery
terminal
with
an
insulator
before
startingdiagnostic,
troubleshooting
or
service
worknot
associated
with
SRS,
and
before
doing
any
welding
on
the
car
.
"
If
an
airbag
has
been
activated
due
to
an
acci-dent,
BMW
specifies
that
SRS
components
be
replaced
.
For
more
information
on
post-collision
SRS
service,
see
an
authorized
BMW
dealer
.
"
Do
not
allow
the
airbag
unit
to
come
in
contact
with
cleaning
solutions
orgrease
.
Never
subject
an
airbag
unit
to
temperatures
aboye
212°F
(100°C)
.
When
reconnecting
the
battery,
no
per-
son
should
be
inside
the
vehicle
.
"
Always
place
an
airbag
unitthat
has
been
re-
moved
from
its
packaging
with
the
padded
sidefacing
upward
.
Do
not
leave
an
airbag
unlt
unat-
tended
.
"
!f
the
airbag
unit
or
airbag
control
modulehas
been
dropped
froma
height
of
!
1
2
meter
(1
Y2
ft.)
ormore,
theairbag
unit
should
not
be
installed
.
Aírbag
system
components
are
shown
in
Fig
.
1.
GENERAL
721-2
AIRBAG
SYSTEM
(SRS)
Fig
.
1
.
Airbag
system
components
.
AIRBAG
SENSORSAND
ELECTRONICS
CA
UTION-
"
If
an
airbag
is
activated,
the
following
compo-
nents
must
be
replaced
:
Airbag
with
contact
ring
;
-Pyrotechnic
seat
belt
tensioners
(if
fitted)
;
-SRS
Control
module
;
-Impact
sensors
;
All
airbags
which
did
not
deploy
.
"
Consult
your
BMW
dealer
for
parts
and
service
information
.
TheE36
airbag
system
consists
of
the
following
compo-
nents
:
crash
sensors
(in
earlycars,
through
1993),
an
elec-
tronic
control/monitoring
module
(with
integrated
crash
sensor
in
ZAE
systems),
an
indicator
light
in
the
instrument
panel,
and
inflatable
airbags
equipped
with
gas
generators
in
the
steering
wheel
and
in
the
passenger
side
of
the
instrument
panel
(ZAE
systems)
.
Some
1997
and
al¡
1998
carsalso
have
side-impact
airbags
in
the
front
doors
.
AIRBAG
SENSORS
AND
ELECTRONICS
1.
Crash
sensors
(through
1993)
wheel
2
.
SRS
control
module
in
front
of
5
.
Side-impact
airbags
(1997/98)
glove
compartment
(through
6
.
ZAE
control
module
under
rear
1993)
seat
(from
1994)
3
.
Passenger
side
airbag
unit
in
7
.
Side-impact
airbag
crash
sensors
dashboard
(ZAE
system)
in
door
silis
(1997/98)
4
.
Driver
side
airbag
unitin
steering
8
.
Knee
bolsters
In
addition
to
the
airbags,
the
vehicles
are
equipped
wíth
knee
bolsters
for
extra
protection
.
SRS
Warning
Light
and
Fault
Display
The
airbag
system
utilizes
a
self-diagnostic
control
module
to
detect
and
store
system
faults
.
If
a
fault
is
detected,
the
SRS
indicator
in
the
instrument
cluster
comes
on
and
stays
on
.
When
the
ignition
key
is
tumed
on,
the
indicator
light
will
illu-
minate
for
approximately
4-6
seconds
.
The
illuminated
light
indicates
the
self-testof
the
electronic
control/monitoring
module,
the
ignítors
and
crash-sensorcircuits,
and
the
system
wiring
.
The
airbag
system
should
be
inspected
byan
autho-
rized
BMW
dealer
if
the
indicator
light
does
not
come
on,
ifit
does
not
go
out
in
approximately
4-6
seconds
after
switching
onthe
ignition,
or
if
the
light
comes
on
during
driving
.
If
the
system
has
detected
a
fault,
the
light
will
come
on
and
stay
on
.
2
INDEX
Brakes
(cont
.)
pressure
bleeding
brakes
(except
cars
wíth
AST)
340-3
troubleshooting
340-1
Brushes,
alternator
See
Battery,
starter,
alternator
Bulbs
See
Exterior
lighting
See
also
Instruments
Bumpers
See
Exterior
trim,
bumpers
C
CamberSee
Steering
and
wheel
alignment
Camshaft
See
Cylinder
head
and
valvetrain
Camshaft
position
sensor
See
Ignition
system
Camshaft
timing
chain
general
information
117-1
camshaft
timingchain,
4-cylinder
117-
2
camshaft
timing
chains,6-cylinder
117-6
camshaft
timing
chain,
removing
(4-cylinder
engines)
117-2
camshaft
timing
chains,
removing
(6-cylinder
engines)
117-7vanos
(variable
valve
timing)
117-14
control
unit,
removing
117-16system
operation,
testing
117-14
Caster
See
Steering
andwheel
alignment
Catalytic
convertor
See
Exhaustsystem
Cautions
viü
Center
bearing
See
Driveshaft
Center
console
See
interior
trim
Central
body
electronics
(ZKE
IV)
515-8
Central
locking
system
(ZVM)
515-7
Centrallocking
and
anti-theft
general
information
515-1
door
handles
and
Iocks
515-1
door
striker,
replacing
515-6
front
door
handle,
removing/
installing
515-3
front
door
lock,
removing/installing
515-1
rear
door
handle,
removing/installing
515-5
rear
door
lock,
removing/installing
515-4
EWS
II
control
module,
replacing
515-10
EWS
II
ring
antenna,
replacing
515-10
EWS
II
transmitter/receiver
module,
replacing
515-11
locking
system
and
electronic
immobilization
515-7
luggage
compartment
locking
actuator,
removing/installing
515-6
Clutch
general
information210-1
clutch
hydraulic
system,
bleeding
and
flushing
210-2
clutch,
inspecting
and
installing
210-5
clutch
master
cylinder,
replacing
210-2
clutch,
removing
210-4
clutch
slave
cylinder,
replacing
210-3
transmission
pilot
bearing,
replacing
210-6
Clutch
fluid
See
Maintenance
program
Coil
See
Ignition
system
Coilspring
See
Rear
suspension
Component
locations
See
Electrical
component
locations
Compressor
See
Air
conditioning
Compressor
clutch
See
Air
conditioning
Condenser
See
Air
conditioningControl
arms
See
Front
suspension
See
also
Rear
suspension
Convertible
top
general
information
541-1
manual
convertible
top
541-1
lid
release
mechanism
541-2
replacing
541-2
visor
latch
541-1
visor
latch
píate
541-1
power
convertible
top
541-2
drive
motor,
replacing
541-7
emergency
operation
541-7
front
latching
mechanism
541-4
lid
541-9
replacing
541-5
visor
latch
541-4
visor
latch
motor541-5
visor
latch
plate
541-4
rollover
protection
system
541-9
Coolant
(Anti-freeze)
See
Maintenance
program
Coolant
pump
See
Cooling
system
Cooling
system
general
information
170-1
cooling
fan,
replacing
170-8
coolant
pump,
replacing
170-10
coolant
pump
and
thermostat170-1
coolant,
draining/filling
170-5
cooling
fans
170-2
cooling
fan,
testing
170-4
cooling
system
service
170-5
cooling
system,
bleeding
(radiator
with
integral
expansion
tank)
170-6
cooling
system
pressure
test
170-3
electric
cooling
fan,
replacing
170-8
radiator,
removing/installing
170-11
Cooling
system
(cont
.)
radiator
and
expansion
tank
170-1
radiator
service
170-11
temperature
gauge
quick
check170-3
thermostat
quick
check
170-3
thermostat,
replacing
170-9
troubleshooting
170-2
warnings
and
cautions
170-2Crankshaft
position/rpm
sensor
See
Ignition
system
Crash
sensor
See
Airbag
system
(SRS)
CV
joint
See
Maintenance
program
See
also
Rear
suspension
Cylinder
head
and
valvetrain
general
information
116-1
camshaft116-7
camshafts,
removing/installing
(M42
engine)
116-1camshafts,
removing/installing
(M44
engine)
116-3
camshafts,
removing/installing
(6-cylinder
engine)
116-4
cylinder
head,
disassembly/assembly
116-1
cylinder
head
and
valvetrain,
reconditioning
116-7
cylinder
head
116-7
hydraulic
cam
followers,
checking
and
replacing
(M42
and
al]
6-cylinder
engines)
116-9
hydraulic
valve
adjusters,
checking
and
replacing
(M44
Engine)
116-8
valve
guides
116-10
valveseats
116-12
valve
springs
116-12
valve
stem
oil
seals
116-11
valves
116-11
valves,
leak
test
116-11
valves,removing/installing
116-6
Cylinder
head
removal
and
installation
general
information
113-1
cylinder
head,
removing/installing
(4-
cylinder
engine)
113-1
cylinder
head
(6-cylinder
engine),
removing/installing
113-10
Dashboard
See
Interior
trim
Deck
lid
See
Trunk
lid
Defogger
See
Heating
Differential
See
Final
drive
DISA
(dual
resonance
intake
system)
See
Fuel
injection
See
also
Engine-general
DME
(digital
motor
electronics)
See
Ignition
system
See
alsoFuel
injection
6
INDEX
Ignition
system
general
information
120-1basictroubleshooting
principies
120-3camshaft
position
(CMP)
sensor
120-
6
camshaft
positíon
(CMP)
sensor,
replacing
(4-cylinder
engine)
120-6camshaft
position
(CMP)
sensor,
replacing
(6-cylinder
engines)
120-7
checking
for
spark
120-3
crankshaftposition/rpm
sensor
120-5
crankshaft
position/rpm
sensor,
testing/replacing
(front
mounted
sensor)
120-6
crankshaft
positíon/rpm
sensor,
testing
(rear
mounted
sensor)
120-6
disabling
ignition
system120-2
ignition
coil,
testing
and
replacing
(4-
cylinder
engines)
120-3
ignition
coil,
testing
and
replacing
(6-
cylinder
engines)
120-4
ignítion
firing
order
120-7
ignition
system
diagnostics
120-3
ignition
system
schematics
120-7
ignition
system
service
120-3knock
sensors,
replacing
120-7warnings
and
cautions
120-2
Inspectíon
I
and
Inspection
II
See
Maintenanceprogram
Instrumentpanel
See
interior
trim
Instruments
general
information
620-1
instrument
cluster,
removinglinstalling
620-1
instrument
cluster,
self-testing
620-1
instrument
cluster
bulbs,
replacing
620-2
multi-information
display
(MID),
620-4
multi-information
display
(MID),
removing/installing
620-4
odometer
coding
plug,
replacing
620-
2
vehicle
speed
sensor,
replacing
620-3
Intake
manifold
4-cylinder
engíne,
removing
113-3
6-cylinder
engine,
removing
113-11
See
alsoCylinder
head
removal
and
installation
Intake
air
temperaturesensor
See
Fuel
injection
Interior
trim
general
information
513-1
center
console,
removing/installing
513-1
dashboard,
removing/installing
513-3
glove
compartment,
removing/
installing
513-2
lower
left
dash
panel,
removing/
installing
513-2
J
Jump
startíng
010-12
K
Knock
sensor
See
Ignition
system
L
Leather
upholstery
See
Maíntenance
program
Leve¡
sender
See
Fuel
pump
Lubrication
system
general
information
119-1
oil
pan,
removing/installing
(4-cylinder
engines)
119-2
oil
pan,
removing/installing
(6-cylinder
engine,
1992models)119-4
oil
pan
119-2
oil
pan,
removing/installing
(6-cylinder
engine,
1993
and
later
models)
119-6
oil
pressure,
checking
119-1
oil
pressure
warningsystem,
testing
119-2
oil
pump
119-8
oil
pump,
removing/installing
(4-cylinder
engine)
119-8
oil
pump,
removing/installing
(6-cylinder
engine)
119-9
troubleshooting
119-1
M
Maíntenance
program
general
information
020-2
accelerator
and
throttle
linkage
020-13
air
filter,
replacing
020-11
automatic
transmission
fluid
020-8
automatic
transmission
service
020-18
battery,
checking
and
cleaning
020-12
battery,
replacing
020-12
BMW
service
indicator
020-2
body
and
hinges,
lubricating
020-19
brake
fluid
020-9
brake
fluid,
replacing
020-17
brake
pad/rotor
wear,
checking
020-17
brake
system,
inspecting
020-17
clutch
fluid,
checking
020-19
cooling
system
service
020-14
drive
axle
joint
boots,
inspecting
020-19
engine
coolant
(anti-freeze)
020-9
engine
drive
belts
020-13
engine
oil,
checking
leve¡
020-9
Maintenance
program
(cont
.)
engine
oil
and
filter,
changing020-9engine
oil
service
020-9
exhaust
system,
inspecting
020-18
exterior
washing020-20
final
drive
gear
oil
020-9
final
drive
oil
level,
checking
020-18
front
suspension
and
steering
linkages,
inspecting
020-18
fuel
filter,
replacing
020-16
fuel
tank
and
fuel
lines,
inspecting
020-19
¡dle
speed
020-12
inspection
I
and
inspection
11
020-2
interior
care020-20
leather
upholstery
and
trim
020-20
maintenance
tables
020-3
manual
transmission
fluid,
checking
and
filling
020-18manual
transmission
fluid
020-8
manual
transmission
service
020-18oxygensensors
020-15
parking
brake,
checking
020-17
polishing
020-20
poly-ribbed
belt,
replacing
020-13
power
steering
fluid
020-9
power
steering
fluid,
checking
leve¡
020-14
rear
suspension,
inspecting
020-18
resetting
service
indicator
020-3
seat
belts
020-20
spark
plugs,
replacing
020-11
special
cleaning
020-20
tires,
checking
inflation
pressure
020-17
tires,
rotating
020-17
v-belt,
replacing
020-13
washing
chassis
020-20waxing020-20
windshield
wiperblade
maintenance
020-19
wheels,
aligníng
020-17
Manual
transmission
See
also
Maintenance
program
See
also
Transmission-general
general
information
230-1
back-up
light
switch,
replacing
230-2
inputshaft
sea¡,
replacing
(transmission
installed)
230-5
output
shaftsea¡,
replacing
(transmission
installed)
230-4
selector
shaft
sea¡,
replacing
(transmission
installed)
230-3
transmission
fluid,
replacing
230-2
transmission
fluidlevel,
checking
230-2
transmission
fluid
service
230-1
transmission
removal
and
installation
230-5
transmission,
removing/installing
230-
6
transmission
service
230-2
Mass
air
flow
sensor
See
Fuel
Injection