1995 BMW M3 fault

00-
6



ELECTRICAL
SYSTEM-GENERAL

Short
circuit,
testing
with
ohmmeter



Short
circuit,
testing
with
voltmeter

1
.
Remove
blown
fuse
from
circuit
and
disconnect
cables



1
.
Remove
blown
fusefrom
circuit
.

from
battery
.
2
.
Disconnect
harness
connector
from
circuifs
loador

2
.
Disconnect
harness
connector
from
circuit's
loador



consumer
.

consumer
.

3
.
Using
an
ohmmeter,
connect
one
test
lead
to
loadside

of
f
use
terminal
(terminal
leading
to
circuit)
and
the
oth-

ertest
lead
to
ground
.
See
Fig
.
4
.

Load
disconnected
from
Battery

LO

n
I



~



Shotrouit
vu
.uto
earthth

Switch

Load

0013241

Fig
.
4
.



Digital
multimeter
being
usedasan
ohmmeter
to
find
short

circuit
.

4
.
lf
there
is
continuity
to
ground,
there
is
a
short
to

ground
.

ELECTRICAL
TROUBLESHOOTING

NOTE-

Most
fuses
power
more
than
one
consumer
.
Be
sure
aff

consumers
are
disconnected
when
checking
for
a
short
circuit
.

3
.
Using
a
voltmeter,
connect
test
leads
across
f
use
termi-

nals
.
See
Fig
.
5
.
Make
sure
power
is
present
ín
circuit
.

lf
necessary
turn
keyon
.

~2
.U

from
Battery

Load
disconnected

Short-circuit
to
earth

I



Fuse
box

0013240

5
.
If
there
is
no
continuity,
work
from
wire
harness
hearest



Fig
.
5
.



Digital
multimeter
being
usedas
a
voltmeter
to
find
short
cir

to
fuse/relay
panel
and
move
or
wiggle
wireswhile
ob-



cuit
.

serving
meter
.
Continue
to
movedown
harness
until

meter
displays
a
reading
.
This
is
the
location
of
short
to



4
.
lf
voltage
is
present
at
voltmeter,
there
is
a
short
to

ground
.



ground
.

Visually
inspect
the
wire
harness
at
this
point
for
any
faults
.



5
.
lf
voltage
is
not
present,
work
from
wire
harness
near-

If
no
faults
are
visible,
carefully
slice
open
the
harnesscover



est
to
fuse/relay
panel
and
move
orwiggle
wireswhile

or
the
wire
insulation
for
further
inspection
.
Repair
any
faults



observing
meter
.
Continue
to
move
down
harness
until
found
.



meter
displays
a
reading
.
This
is
the
location
of
short
to

ground
.

6
.
Visually
inspect
wire
harness
atthis
point
for
any
faults
.

lf
no
faults
are
visible,
carefully
slice
open
harness
cov-
erorwire
insulation
for
further
inspection
.
Repair
any

faults
found
.

INSTRUMENT
CLUSTER
....
.
.
.
.
.
...
.
..
620-1

Instrument
cluster,
seif-testing
.
.
.......
.
..
620-1

Instrument
cluster,
removing
and
installing
...
620-1

Instrument
cluster
bulbs,
replacing
.
.
.
.
.
.
...
620-2

GENERAL

This
repair
group
covers
removal
and
installation
of
the
in-
strument
cluster
and
the
Multi-information
Display
(MID)
mod-
ule
.
Bulb
replacement
information
for
these
units
is
also
included
here
.

NOTE
-

A
quick
check
of
the
temperature
gauge
and
its
electri-
cal
circuitis
given
in
170
Radiator
and
Cooling
Sys-
tem
.
Use
this
procedure
to
diagnosea
faulty
temperature
gauge

INSTRUMENT
CLUSTER

When
servicing
the
instrument
cluster,
always
disconnect
the
negative
(-)
cable
from
the
battery
and
insulate
the
cable
end
to
prevent
accidental
re-connection
.

Instrument
cluster,
seif-testing

Severa¡
different
versions
of
the
basic
instrument
cluster
havebeen
fitted
in
E36
cars
.
It
is
possibleto
perform
an
instru-
ment
cluster
test
and
display
system
test
information
.

Some
of
the
information
displayed
by
the
instrument
cluster
during
seif-testing
is
used
for
interna¡
BMW
organizationpur-
poses,
suchasmatching
the
correct
instrument
cluster
com-
ponents
during
parts
replacement
.
Other
functions
test
the
various
instrument
modules
.
Self-test
is
also
used
to
recode
the
instrument
cluster
after
removal
.

In
later
production
vehicles
(1996
and
later)
the
test
results
canbe
downioaded,
via
the
diagnostic
plug,
byan
authorized
BMW
dealertechnician
.

1
.
Turn
ignition
to
"radio"position
.

2
.
Press
and
hold
reset
button
on
trip-odometer
untiltrip-
odometer
display
shows
numerical
codes
.

620
Instruments

4
.
Turn
off
ignition
.

Instrument
cluster,

removing
and
installing

INSTRUMENTS
620-1

GENERAL
.....
.
.
.
.
.
.
.
.
.
.........
.
....
620-1



Odometer
coding
plug,
replacing
.....
.
.
.
.
.
.
620-2

Vehicle
speed
sender,
replacing
...
.
.
.
.
.
.
.
.
620-3

MULTI-INFORMATION
DISPLAY
(MID)
.
.
.
620-4

Multi-Information
Display,
removing
and
installing
..
.
....
.
.........
620-4

3
.
With
each
subsequent
press
of
the
button,
a
different
function
is
tested
.
Some
functions
will
activate
need1e
gauges
.

1
.
Disconnect
negative
(-)
cable
from
battery
and
cover
terminal
with
insulating
material
.

CAUTION-

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

2
.
Remove
airbag
unit
from
steering
wheel
.
See
721
Air-
bag
System
(SRS)
.
Store
unit
in
a
safe
place
.

WARNING
-

The
airbag
is
an
explosive
devfce
and
should
be
treated
with
extreme
caution
.
Improper
handling
of
the
airbag
could
cause
serious
injury
or
death
.
Store
the
airbag
with
the
horn
pad
facing
up
.
If
stored
facing
down,
accidental
deployment
couldpropel
it
vfolently
into
the
air,
causing
injury
.

3
.
With
front
wheels
pointed
straight
ahead,
remove
steer-
ing
wheel
.
See
320
Steering
and
Wheel
Alignment
.

4
.
Remove
instrument
cluster
retaining
screws
.
See
Fig
.
1
.

5
.
Place
a
towel
over
steering
column
.
Carefully
tilt
top
of
cluster
out
of
dash
panel
.
Unlock
and
disconnect
har-
ness
connectors
from
back
of
cluster
.
See
Fig
.
2
.

INSTRUMENT
CLUSTER

620-2
INSTRUMENTS

Fig
.1.



Instrument
cluster
retaining
screws
(arrows)
.

INSTRUMENT
CLUSTER

0012562

Fig
.
3
.



Turnbulb
base
45°
in
direction
shown
(arrow)
.

l
v



w
r
v
9



10



11



12



13



14



15



16



)7



18



19



20
y
21

1
.
Temperature
warning



12
.
Brake
fluid
warning

oo13n6



2
.
Right
turn
signal



13
.
Brake
pad
wear
warning
3
.
Instrument
lighting



14
.ABS
warning
Fig
.
2
.



Instrument
cluster
connector
locking
lever
(arrow)
.



4
.
Oil
pressure
warning



15
.
Seat
belt
warning5
.
Highbeam



16
.ASTwarning
6
.
Battery
charging
lamp



17
.Check
control
6
.
Installation
is
reverse
of
removal,
noting
the
following
:



7
.
Left
turn
signal



18
.Check
engine

"
Instrument
cluster
harness
connector
locking
levers



8
.
Low
fuel
warning



19
.
LCD
lighting

must
be
in
up
position
before
installing
connector
.



9
.
Airbag
warning



20
.
Rear
foglight
(not
used)
10
.
Catalytic
converter
warning



21
.
Front
foglights
"
Install
airbag
to
steering
wheel
as
described
in
721



11
.
Emergency
brake
Airbag
System
(SRS)
.



0012563

"
Reconnect
negative
(-)
cable
to
battery
last,
once
al¡



Fig
.
4
.



Bulb
designation
chart
.

harness
connectors
have
been
reconnected
.

"
Recode
cluster
as
described
in
Instrument
cluster,



CAUTION-
seif-testing
.



Note
wattage
of
bulb
.
Excessive
wattage
could
melt
cluster
housing
.
Replace
defective
bulbs
with

Instrument
cluster
bulbs,
replacing



reptacementbulbs
of
the
same
wattage
.

1
.
Remove
instrument
cluster
as
described
above
.



Odometer
coding
plug,
replacing

2
.
Remove
faulty
bulb
by
turning
bulb
base
45°
inits

mount
and
remove
from
housing
.
See
Fig
.
3
.



The
coding
plug
maintains
a
record
of
thevehicle
mileage
.

The
back
of
the
instrument
cluster
and
its
bulb
locations
are



1
.
Record
vehicle
mileage
.

shown
in
Fig
.
4
.
2
.
Remove
instrument
cluster
as
described
earlier
.

620-
4
INSTRUMENTS

MULTI-INFORMATION
DISPLAY
(MID)

Severa¡
different
versionsof
the
Multi-Information
Display,

have
been
installed
in
E36
cars
.
The
top-of-the-line
model
is

called
the
Oh-BoardComputer
.
See
Fig
.
8
.

Ambient
temperature/ciock

Check
control/clock

0013028

Fig
.
8
.



Different
versions
of
Multi-Information
Display
(MID)
installed
in
E36
cars
.

Multi-Information
Display,

removing
and
installing

The
Multi-Information
Display
(MID)
is
illuminated
by
bulbs
.

It
mustbe
removed
to
replace
the
bulbs
.
Bulb
replacement
is

included
in
this
procedure
.

1
.
Remove
dashboard
parcel
shelf
.
Reach
under
MID

module
and
pushoutward
.
See
Fig
.
9
.

2
.
Slide
harness
retaining
lever
forward
to
release
MID

from
wiring
harness
.
See
Fig
.
10
.

3
.
To
Rmove
a
faulty
bulb,
use
anarrow
screwdriver
to

turn
bulb
base
45°
counter
clockwíse
.
See
Fig
.
11
.

MULTI-INFORMATIONDISPLAY
(MID)

111

Fig
.
9
.



Removing
the
Multi-Information
Display(MID)
module
.

0012564

Fig
.
10
.
MID
wiring
harness
release
lever
(arrows)
.

Fig
.
11
.
Turn
bulb
base
45°
counterclockwise
.

4
.
Installation
is
reverse
of
removal
.

0012566

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
.

Fig
.
8
.



Airbag
crash
sensor
mountingscrews
(arrows)
on
early
cars
.
Note
Torx
screws
with
anti-tamper
pin
in
screw-head
.

ZAE
control
module,
replacing

NOTE-

Some
versions
of
early
ZAE
control
modules
are
no
longer
available
from
BMW
.
When
replacing
control
modules
on
cars
built
between
September
1993
and
June
1994,
consulta
BMW
parts
department
for
the
lat-
est
information
on
retrofitting
the
later
module
.
3
.
Remove
orange
SRS
connector
from
its
holder
and
carefully
separate
connector
.
Refer
to
Fig
.
7
.
1
.
Disconnect
negative
(-)
cable
from
battery
and
cover

negative
terminalwith
insulating
material
.



4
.
Working
behind
steering
wheel,
completely
loosen
Torx

screws
(T30)
while
holdingairbag
in
place
.
See
Fig
.
9
.
2
.
Lift
rearseat
cushion
.
Unplug
harness
connectors
and



Support
airbag
unit
toprevent
it
from
falling
out
.
remove
ZAE
airbag
control
module,
which
is
bolted
to

top
of
driveshaft
tunnel
.

3
.
Installation
is
reverse
of
removal
.

Front
side-impact
airbag
crash
sensor,

removing
and
installing

1
.
Disconnect
negative
(-)
cable
from
battery
and
cover

negative
terminal
with
insulating
material
.

2
.
Remove
front
seat
.
See520
Seats
.

3
.
Convertible
:
remove
rear
seat

4
.
Remove
plastic
door
sill
trim
.

5
.
Fold
up
carpet
in
back
of
front
seat
.

6
.
Pull
off
connector
from
crash
sensor,
which
is
located

under
rugnext
to
door
si¡¡
.

7
.
Remove
sensorby
removing
screws
.
Note
direction
ar-

row
before
removing
sensor
.

8
.
Installation
is
reverse
of
removal,noting
direction
arrow

on
sensor
.

AIRBAGS

AIRBAG
SYSTEM
(SRS)



721-
5

Driver
side
airbag,

removing
and
installing

1
.
Disconnect
negative
(-)
cable
from
battery
and
cover
negative
terminal
with
insulating
material
.

WARNING
-

On
cars
with
ZAE
system
:
If
theairbag
system
has
detected
a
fault
(SRS
indicator
illuminated),
a
wait-
ing
period
ofat
least
ten
minutes
must
be
observed
before
removing
the
airbag
from
the
steering
wheel
.
This
will
allow
the
system
capacitor
to
discharge,
re-
ducing
the
possibility
of
a
trigger
pulsebeinggener-
ated
to
the
airbag
.

CAUTION-

Prior
to
disconnecting
the
battery,
read
the
battery
disconnection
cautions
given
at
the
front
of
this
manual
on
page
vi¡¡
.

2
.
Remove
lower
steering
column
trim
mounting
screw

andremove
lower
trim
.
Refer
to
Fig
.
6
.

Fig
.
9
.



Driver
sideairbag
unit
mounting
screws
(arrows)
.

0011893

AIRBAGS

721-
6



AIRBAG
SYSTEM
(SRS)

5
.
Carefully
lift
airbag
unit
off
steering
wheel
and
discon-



6
.
Installation
is
reverse
of
removal
.
Tighten
right
side
nect
orange
harness
connector
from
rear
of
airbag
unit
.



screw
on
airbag
first
(as
viewedfrom
driver's
seat),

See
Fig
.
10
.



then
left
side
screw
.

NOTE-



NOTE-

In
some
models,
theairbag
electrical
connection
to
the



If
there
is
no
electrical
harness
connector
between
the
steering
wheel
isvia
aplug
in
back
of
the
airbag
unit
.



airbag
and
the
steering
wheel,
be
sure
to
fit
the
push
There
is
no
wire
harness
to
disconnect
.



in
electrical
plug
in
back
of
the
airbag
finto
the
proper
re-
ceptacle
in
the
steering
wheel
.

Fig
.
10
.
Driver
sideairbag
unit
harness
connector
(arrow)
.

AIRBAGS

WARNING
-

"
Store
the
removed
airbag
unit
with
the
horn
pad
facing
up
.
If
stored
facing
down,
accidental
de-
ployment
couldpropel
it
violently
into
the
air,
causing
injury
.

"
Once
an
airbag
is
removed,
the
car
must
not
be
driven
.

"
Do
not
connect
the
battery
with
the
airbag
dis-
connected
.
A
fault
code
will
be
stored,
setting
off
the
SRS
warning
light
.
Special
tools
are
needed
to
reset
the
fault
memory
.

"
Special
instructions
apply
when
installing
an
air-
bag
equipped
steering
wheel
.
See
320
Steering
and
Wheel
Alignment
.

"
Once
the
airbag
unit
is
installnd
and
all
other
ser-vice
procedureshave
been
completed,
start
the
engíne
and
check
that
the
SRS
warning
light
goes
out
.
If
the
warning
light
stays
on,
the
SRS
system
will
not
function
as
designed
.
Have
the
system
diagnosed
and
repaired
by
an
authorized
BMW
dealer
.

0013184

Tightening
Torque

"
Airbag
unitto
steering
wheel
........
8
Nm
(71
in-lb)

Passenger
side
airbag,

removing
and
installing

1
.
Disconnect
negative
(-)
cable
from
battery
and
cover
negative
terminal
with
insulating
material
.

2
.
Remove
glove
compartment
.
See
513
Interior
Trim
.

3
.
Lift
cover
from
topof
passenger
sideairbag
on
dash-
board
.
See
Fig
.
11
.

0013108
Fig
.
11
.
After
removing
glove
compartment,
lift
out
passenger
side
air-
bag
cover
.
Note
airbag
mounting
bolts
(A)
and
airbag
electri-
cal
connector
(B)
.

4
.
Remove
passenger
sideairbag
mounting
bolts
.
Dis-
connect
electrical
harness
connector
from
rear
of
air-
bag
unit
and
remove
airbag
.

5
.
Installation
is
reverse
of
removal
.
Make
sure
wiring
har-
ness
is
not
pínched
when
installing
airbag
unit
in
dash-board
.