1996 BMW 325i Switches

600-
4



ELECTRICAL
SYSTEM-GENERAL

Voltage
and
Voltage
Drops

The
wires,
connectors,
and
switches
that
carry
current
are

designed
with
very
low
resistance
so
that
current
flows
with
a

minimum
loss
of
voltage
.
A
voltage
drop
is
caused
by
higher
than
normal
resistance
in
a
circuit
.
This
additional
resistance

actually
decreases
or
stops
the
flow
of
current
.
A
voltage
drop

can
be
noticed
byproblems
ranging
fromdim
headlights
to
sluggish
wipers
.
Some
common
sources
of
voltage
drops
are
corroded
or
dirty
switches,
dirty
or
corroded
connections
or

contacts,
and
loose
or
corroded
ground
wires
and
ground
con-

nections
.

A
voltage
drop
test
is
a
good
test
to
make
if
current
is
flowing
through
the
circuit,
butthe
circuit
is
not
operating
correctly
.
A
voltage
drop
test
will
help
to
pinpoint
a
corroded
ground
strap
or
a
faulty
switch
.
Normally,
there
should
be
less
than
1
volt

drop
across
most
wires
or
closed
switches
.
A
voltage
drop
across
a
connector
or
short
cable
shouldnot
exceed
0
.5
volts
.

Voltage,
measuring

1
.
Connect
digital
multimeternegative
lead
to
a
reliable
ground
point
oncar
.

NOTE-

The
negative
(-)
battery
terminal
is
alwaysa
good
ground
point
.

2
.
Connect
digital
multimeter
positive
lead
to
point
incir-
cuit
you
wish
to
measure
.
See
Fig
.
1
.
If
a
reading
is
ob-
tained,
current
is
flowing
through
circuit
.

NOTE-

The
voltage
reading
shouldnot
deviate
more
than
1
volt
from
the
voltage
at
the
battery
.
If
the
voltage
drop
is
more
than
this,
check
for
acorroded
connector
or
cose
ground
wire
.

ELECTRICAL
TROLIBLESHOOTING

from
Battery

Fig
.
1
.



Digital
multimeterbeing
used
to
test
voltage
.

No
voltage
r_l

-1
Load

LJ

Switch

NOTE-

The
maximum
voltage
drop
in
an
automotive
circuit,
as
recommended
by
the
Society
of
AutomotiveEngineers
(SAE),
is
as
follows
:
0
voltsfor
small
vire
connections
;
0
.1
Volts
for
high
current
connections
;
0
.2
volts
for
high
current
cables
;
and
0
.3volts
for
switch
or
solenoidcon-
tacts
.
On
longer
wires
or
cables,
the
drop
may
be
slight-ly
higher
.
In
any
case,
a
voltage
drop
of
more
than
1.0volt
usually
indicates
a
problem
.

0013238

NOTE-

"
A
voltage
drop
test
is
generally
more
accuratethan
a



Voltage
drop,
testing

simple
resistance
check
because
the
resistances
in-
volvedare
often
too
small
to
measure
with
most
ohm-



Voltage
drop
can
only
be
checked
when
current
is
running
meters
.
For
example,
a
resistance
as
small
as0
.02



through
the
circuit,
suchasby
operating
the
starter
motor
or
ohms
would
results
in
a
3
volt
drop
in
a
typical
150



turning
onthe
headlights
.
A
digital
multimeter
should
beused
amp
starter
circuit
.
(150
amps
x
0
.02
ohms
=3
volts)
.



lo
ensure
accurate
readings
.

"
Keep
in
mind
that
voltage
with
the
key
on
and
voltage
with
the
engine
running
arenotthe
same
.
With
the
ig-



1
.
Connect
digital
multimeter
positive
lead
to
positive
(+)
nition
on
and
the
engine
off
(battery
voltage),
voltage



battery
terminalor
a
positive
power
supply
close
lo
bat
should
be
approximately
12
.6volts
.
With
the
engine



tery
source
.
running
(charging
voltage),
voltage
should
be
approx-
imately
14
.0
volts
.
Measure
voltage
at
the
battery
with



2
.
Connect
digital
multimeter
negativelead
to
other
end
of
the
ignition
on
and
then
with
the
engine
running
to
get



cable
orswitch
being
tested
.
See
Fig
.
2
.
exact
measurements
.

3
.
With
power
on
and
circuit
working,
meter
shows
volt-
age
drop
(difference
between
two
points)
.
This
value
should
not
exceed
1
volt
.

Continuity,
checking
Short
Circuits

from
Battery

CAUTION-

Use
only
a
high
quality
digital
ohmmeter
having
high
input
impedance
when
checking
electronic
componente
.
The
internal
power
source
used
in
most
analog
(swing-need1e)
meterscan
damage
solidstate
components
.

0013239

Fig
.
2
.



Digital
multimeter
being
used
to
check
for
voltage
drop
across
a
switch
.

The
continuity
test
can
beused
to
check
a
circuit
or
switch
.
Because
most
automotive
circuits
are
designed
to
have
little

or
no
resistance,
a
circuit
or
part
of
a
circuit
canbe
easily

checked
for
faults
using
an
ohmmeter
.
An
open
circuit
or
a
cir-

cuit
withhigh
resistance
will
not
allow
current
to
flow
.
A
círcuit
with
little
or
no
resistanceallows
current
to
flow
easily
.

When
checking
continuity,
the
ignition
should
be
off
.
On
cir-
cuits
that
are
powered
at
all
times,
the
battery
should
be
dis-
connected
.
Using
the
appropriate
wiring
diagram,
a
circuit
can
be
easily
tested
for
faulty
connections,
wires,
switches,
relays,
and
engine
sensorsby
checking
forcontinuity
.
For
a
continu-
ity
check
on
a
brake
light
switch,
see
Fig
.
3
..

A
short
circuit
is
exactly
what
the
narre
implies
.
The
circuit
takes
a
shorter
paththan
it
was
designed
to
take
.
The
most

common
short
that
causes
problems
is
a
short
to
ground

where
the
insulation
on
a
positive
(+)
wire
wears
away
and
the

metal
wire
is
exposed
.
When
the
wire
rubs
against
a
metal

partof
thecar
or
other
ground
source,
the
circuit
is
shorted
to
ground
.
If
the
exposed
wire
is
live
(positive
battery
voltage),
a

Puse
will
blow
and
the
circuit
may
possibly
be
damaged
.

ELECTRICAL
SYSTEM
-
GENERAL
600-
5

Brake
light
switch

Brake
pedal
in
rest
position

Q

Brake
pedal
depressed
Brake
light
switch

Fig
.
3
.



Brake
light
switchbeing
tested
for
continuity
.
With
brake
ped-
alin
rest
position
(switch
open)
there
is
no
continuity
(infinite
ohms)
.
With
pedal
depressed
(switch
closed)
there
is
continu-
ity
(zero
ohms)
.

Shorts
to
groundcanbe
located
with
a
digital
multimeter
.
Short
circuits
are
often
difficult
to
locate
and
may
vary
in
na-
ture
.
Short
circuits
can
befound
using
a
logical
approach
based
onthe
current
path
.

CAUTION
-

"
On
circuits
protected
with
high
rating
fuses
(25
amp
and
greater),
the
wires
or
circuit
compo-
nents
may
be
damaged
before
the
fuse
blows
.
Always
check
for
damage
before
replacing
fuses
of
this
rating
.

"
When
replacing
blown
fuses,
use
only
fuses
hav-
ingthe
correct
rating
.
Always
confirm
the
correct
fuse
rating
printed
on
the
fuselrelay
panelcover

DC

ELECTRICAL
TROUBLESHOOTING

610-$



ELECTRICAL
COMPONENT
LOCATIONS

Fig
.
24
.
Brake
pedalswitches
.

Fig
.
25
.
Driver
side
airbag
connector
(arrow)
.

COMPONENT
LOCATIONS

0011751

Fig
.
26
.
Passenger
sideairbag
connector
(arrow)
behind
glove
com-

partment
.

Fig
.
27
.
Antenna
diversity
module
(arrow)
inleft
C-pillar
.

Fig
.
28
.
Right
side
offuel
tank
under
rear
seat
cushion
.

0013108
0013010
0013142

611
Wipers
and
Washers

GENERAL
..
.
.
.
.
.
.
.
.
.
.
.
.
.
.....
.
......
.
611-1



Windshield
wiper
motor,

removing
and
installing
.
...............
.611-8

WIPER
BLADES
.
.
.
.....
.
.
.
.
.
.
...
....
.611-1

Wiper
Blade
Cleaning
Problems
.
.
.
.
.
.
.....
611-1

Wiper
blades,replacing
...
.
.
.
.
.
.
.
.
.
.....
611-1

Wiper
blade
inserts,
replacing
.
.
.
.
.
.
.
.
.....
611-2

Wiper
arms,
removing
and
installing
.
.
.
.....
611-2

WINDSHIELD
WIPER
ASSEMBLY
.
.
.....
611-3

Windshield
wiper
assembly,
removing

and
installing
(4-door
models)
.
.
.
.
.
.
.....
611-3

Windshield
wiper
assembly,
removing

and
installing
(2-door
models)
.
.
.
.
.
.
.....
611-5

GENERAL

This
repair
group
covers
windshield
wiper
and
washer
sys-

tem
repair
information
.
Please
note
that
some
procedures
are

different
for
2-
and
4-door
models
.

The
windshield
wiper/washer
stalk
switch
assembly
is
cov-

ered
in
612
Switches
and
Electrical
Accessories
.
Electrical



NOTE-
wiring
diagrams
and
relays
for
the
wiper/washer
system
are



BMwhas
available
a
special
toollgauge
(BMWspecial
covered
in
Electrical
Wiring
Diagrams
.



tool
no
.
00
9210)
to
align
the
angle
of
the
wiper
arm
to
the
windshield
glass
.

WIPERBLADES

CA
UTION-

Never
turn
on
the
wiper
blades
while
the
hood
is
open
.
Damage
to
the
wiper
system
and
hood
may
occur
.
Toensure
safetyduring
wiper
biade
system
procedures,
remove
the
windshieldwiper
fuse
.
See
610
Electrical
Component
Locations
.

Wiper
Blade
Cleaning
Problems

Common
cleaning
problems
with
thewipers
includestreak-

ing
or
sheeting,
waterdrops
after
wiping,
and
blade
chatter
.

Streaking
is
usually
caused
when
wiper
blades
are
coated

with
road
film
or
car
wash
wax
.
Clean
the
blades
using
soapy

water
.
If
cleaning
does
not
cure
the
problem,
the
blades
should
be
replaced
.
BMW
recommends
replacing
the
wiper

blades
twice
a
year,
before
and
after
the
cold
season
.

WIPERS
AND
WASHERS



611-1

WINDSHIELD
CLEANING
SYSTEM
......
611-9

Windshield
spray
nozzle,

removing
and
installing
.......
.
........
.611-9

Washer
fluid
reservoir,
replacing
.........
.611-9

Windshield
washer
fluid
pump,
replacing
..
.
......
.
........
.611-9

Washer
fluid
level
sensor,
replacing

(models
with
check
control)
.
.
.
.
........
611-10

Wiper
blade
chatter
may
be
caused
by
dirty
or
worn
blades,

or
by
wiper
arms
that
areout
of
alignment
.
Clean
the
blades
and
windshield
as
described
above
.
Adjust
the
wiper
arm
so

that
there
is
even
pressure
along
the
blade,
and
so
that
the

blade
at
rest
is
perpendicular
to
the
windshield
.
If
problems

persist,
theblades
and
wiper
arms
should
be
replaced
.

The
wiper
blades
can
be
renewed
in
one
of
two
ways
:
either

by
replacing
the
complete
blade
or
by
replacing
just
therubber

insert
.

Insert
replacement
is
the
mosteconomicalmethod,
al-

though
overtime
the
wiperblade
itselfwill
become
worn
.
One

ruleof
thumb
wouldbe
to
replace
just
the
inserts
every
second

time
.

Wiper
blades,
replacing

1
.
Pivot
wiper
arm
off
windshield
.

2
.
Position
wiperblade
approximately
perpendicular
to

wiper
arm
.

3
.
Remove
wiperblade
from
wiper
arm
by
depressing
re-

taining
tab
and
sliding
blade
out
of
arm
.
See
Fig
.
1
.

Drops
that
remain
behind
after
wiping
are
usually
caused
by



NOTE-

oil,
road
film,
or
diesel
exhaust
residue
onthe
glass
.
Use
an



Some
wiperblade
versions
may
havetwo
retaining

alcohol
or
ammonia
solution
or
a
non-abrasive
cleaner
(such



tabs
.

a
s
Bon-Ami



to
clean
the
windshield
.

GENERAL

612
Switches
and
Electrical
Accessories

GENERAL
.
.
.
.
.
.
.
.
.
...
.
.
.
.
.
...
.
......
.612-1



Headlight
switch,
replacing



..
.
...
.
.
.
.
.
.
.
.
.
612-5

Foglight
switch,
replacing
....
.
.
.
.
.
.
.
.
.
.
.
.
.
612-5
INTERIOR
SWITCHES
.
.
...
.
.
.
.
.
.
.
.....
612-1



Hazard
warning
switch,
replacing
.
.
.
.
.
.
.
.
.
.612-5
Turn
signal
switch
and
wiper
switch,



Powerwindow
switch,
replacing
.
.
.
...
.
.
.
.
.
612-5
replacing
.
.
.
.
.
.
.
...
.
.
.
.....
.
....
.
.
.
.
612-1



Outside
mirrorswitch,
replacing
.
.
.
.
.....
.
.
.612-6
Ignition
Switch
Assembly
.
.
.
.
.
.
.
.
....
.
...
612-3

Ignition
electrical
switch,
replacing
.
...
.
....
612-3



INTERIOR
LIGHTS
.
.
................
.
..
612-6

Ignition
lock
cylinder,
replacing
.
.
.
.
.....
.
..
612-4



Dome
light,
rear
map
lights,
trunk
light,

Headlight
and
Foglight
Switch
Assembly
.
.
.
.
612-5



replacing
bulbs
.
......
.
.
.
.
.
.
.
.
.
.....
.
.612-7

GENERAL



Turn
signal
switch
and
wiper
switch,

replacing
Thissection
covers
replacement
of
interior
switches
and
accessories
.



The
procedures
for
removing
the
turn
signal
stalk
switch
and
the
wiper
system
stalk
switchare
similar
.
When
working
on
electrical
switches,
always
disconnect
the
negative
(-)
cable
from
the
battery
and
insulate
the
cable
end
to
prevent
accidental
re-connection
.

CAUTION-

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

WARNING
-

The
cars
covered
by
this
manual
are
equipped
with
a
Supplemental
Restraint
System
(SRS)
that
auto-'
matically
deploys
one
or
more
airbags
.
Each
airbag
unit
houses
an
explosive
powerful
charge
.
Any
work
involving
the
SRS
system
should
only
be
per-
formed
byan
authorized
BMW
dealer
.
Making
re-
pairs
without
the
proper
knowledge
and
special
test
equipment
may
cause
serious
personal
injury
.
See
721
Airbag
System
(SRS)

3
.
With
front
wheels
pointed
straight
ahead,
remove
steer-
"
Testing
and
replacement
information
for
the
oil
ores-



¡ng
wheel
.
See
320
Steering
and
Wheel
Alignment
.
sure
switch
is
covered
in
119
Lubrication
System
.

NOTE-

"
Wirfng
diagramscan
be
found
in
Electrical
Wiring
Diagrams
.

"
Fuse,
relay
and
electrical
component
locations
can
be
found
in
610
Electrical
Component
Locations
.

"
Replacement
information
for
thetransmission
gear
position/neutral
safety
switch
is
covered
in
250
Gear-
shift
Unkage
.

INTERIOR
SWITCHES

NOTE
-

To
preventmarring
interior
trim,
wrap
the
tips
of
screw-
drivers
and
pliers
with
tape
beforeprying
out
switches
or
electrical
accessories
.

SWITCHES
AND
ELECTRICAL
ACCESSORIES



612-1

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

2
.
Remove
airbag
unit
from
steering
wheel
.
See
721
Air-
bag
System
(SRS)
.
Store
airbag
unit
in
a
safe
placew¡th
pad
facing
up
.

NOTE
-

To
helo
with
reassembly,
mark
steering
wheel
and
col-
umn
before
disassembly
.

4
.
Remove
trim
panel
from
lower
left
side
of
instrument
panel
.
See513
Interior
Trim
.

INTERIOR
SWITCHES

612-2



SWITCHES
AND
ELECTRICAL
ACCESSORIES

5
.
Remove
lower
steering
column
cover
from
steering
col-

umn
.
See
Fig
.
1
.

uu12543

Fig
.
1
.



Lower
steering
column
cover
retaining
screw
(arrow)
.

6
.
Remove
stalk
switch
holder
retaining
screw
.
See
Fig
.
2
.

Fig
.
2
.



Stalk
switch
holder
retaining
screw
(arrow)
.

0012555

7
.
Depress
retaining
tabs
to
release
stalk
switchholder
.

Push
stalk
switchholder
downwards
and
off
steering

column
.
See
Fig
.
3
.

8
.
Depress
catches
on
stalk
switch
and
release
switch

from
columna
See
Fig
.
4
.

9
.
Cut
wíre
ties
retaining
harness
to
steering
column
.
Dis-

connect
switch
electrical
connector
located
at
bottom
of

steeringshaft
.

10
.
Installation
is
reverse
of
removal,
noting
the
following
:

"
Place
turn
signal
indicator
in
center
position
before
in-

stalling
.

"
Ensure
that
self
cancelling
cams
on
turn
signal
switch

are
not
damaged
during
installation
.

INTERIOR
SWITCHES

WARNING
-

Once
theairbag
unit
is
installed
and
all
other
ser-
vice
procedures
havebeen
completed,
start
theen-

gine
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
.

0012545

Fig
.
3
.



Depress
retaining
tabs
(arrows)
and
push
holder
down-

wards
.

0012556

Fig
.
4
.



Depress
upper
and
lower
catches
simultaneously
and
unplug

harnessconnector
.

Tightening
Torques

"
Steering
wheel
to
steering

column
spindle
(Bolt)
...
.
.
.
..
.....
63
Nm
(46
ft-lb)

Ignition
Switch
ASsembly



3
.
Remove
screw
retaining
lower
steering
column
cover
and
remove
cover
.
Refer
to
Fig
.
1
.



,

The
components
of
the
ignition
switch
assembly
are
shown

in
Fig
.
5
.
The
ignitionelectrical
switch
and
the
ignition
lock
cyl-

inder
can
be
removed
with
the
ignition
switch
assembly
at-

tached
to
the
steering
column
.

ignition
electrical
switch,
replacing

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

CAUTION
-

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

2
.
Remove
trim
panel
from
lower
left
side
of
instrument

panel
.
See
513
Interior
Trim
.

F~
"

Fig
.
5
.



Ignition
switch
assembly
.

SWITCHES
AND
ELECTRICAL
ACCESSORIES



612-3

4
.
Clean
away
colored
sealer
from
ignition
switch
set

screws
and
remove
slotted
set
screwson
both
sides
of

switch
.
See
Fig
.
6
.

5
.
Release
tabs
andremove
switch
after
separating
elec-
trical
harness
connector
.

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

3



EWS
II
ring
antenna
(Jan
.
1995
and
later
models)

"
Before
mating
ignition
electrical
switch
toignitionlock,

check
that
switch
isin
correct
position
relativetoigni-
tion
lock
.

"
Seal
set
screws
using
paint
or
lacquer
.

0012241

INTERIOR
SWITCHES

612-4



SWITCHES
AND
ELECTRICAL
ACCESSORIES

Fig
.
6
.



Ignition
switch
set
screws
(arrows)
.

Ignition
lock
cylinder,
replacing

NOTE-

On
cars
with
EWS
11(production
date
1/95
and
later),
the
ring
antenna
surrounding
the
ignition
switch
must
be
removed
.
See
515
Central
Locking
and
Anti-theft
.

1
.
Insert
master
key
finto
lock
cylinder
and
turn
60°
to
"ra-
dio"
position
.
See
Fig
.
7
.

Fig
.
7
.



Turn
ignition
switch
60°
to
"radio"
position
(arrow)
.

2
.
Insert
a
thin
piece
of
stiff
wire
into
opening
in
lock
cylin-
der
and
pull
lockcylinder
out
.
See
Fig
.
8
.

NOTE-

On
early
cars
(up
to
production
date
1ol95),
turn
lock
cylinder
back
12°
to
release
.

INTERIOR
SWITCHES

0012555
0011807
0011808

Fig
.
8
.



With
ignition
key
in
"radio"position,
insert
stiff
wire
into
lock
opening
to
release
cylinder
.

Headlight
and
Foglight
Switch
Assembly

The
headlight
and
foglight
switches
are
retained
in
the
left

dashboard
insert
.
This
alsocontains
the
driver's
side
face
lev-

e¡
air
vents
.
To
service
either
switch,
remove
insert
byremov-
ing
a
single
screw
.
See
Fig
.
9
.

NOTE-

Access
to
electrical
hamess
connectors
behind
dash
insert
may
be
easier
if
lower
left
dash
trim
and
driverside
knee
bolsterare
removed
.
See
513
Interior
Trim
.

Fig
.
9
.



Remove
retaíning
screw
to
pull
out
left
dash
insert
(arrow)
.