1998 BMW 328i disconnecting battery

GENERAL

This
repair
group
covers
removal
and
installation
of
the

front
and
rear
seats
.

FRONT
SEATS

The
front
seats
installed
in
E36
cars
come
in
either
manual

or
electrically
powered
versions
.
Cloth,vinyl
and
leather
ver-

sions
are
offered
.
M3
sport
seats
have
extra
bolsters
on
the

sides
of
the
sean-back,
a
thigh
support
bolster,
and
extra
con-

trols
for
sean
inclination
.

Seat
removal
and
installation
is
similar
for
all
versions
.
Seat
disassembly
differs
in
details
among
the
many
models
of

seats
.

Front
seat,
removing
and
installing

1
.
Move
seat
to
fui¡
forward
position
and
raise
it
as
far
as

possible
.
Remove
two
mounting
bolts
at
rear
of
sean

rails
.
See
Fig
.
1
.

2
.
Move
seat
to
fui¡
rear
position,
keeping
it
raised
.

3
.
Disconnect
negative
(-)
cable
from
battery
.



Fig
.1
.



Frontseat
rear
mounting
bolts
(arrows)
.

CAUTION-

Prior
to
disconnecting
the
battery,
read
the
battery
disconnection
cautions
given
at
the
front
of
this

manual
onpage
viii
.

520
Seats

SEATS
520-1

GENERAL
...
.
.
.
.
.
.
.
.
.
..............
.
.
520-1



Rear
seat
cushion
and
backrest,

removing
and
installing

FRONT
SEATS
.
.
.
.
.
.
......
.
.
.
...
.
.
.
.
.
.
520-1



(fixed
seat
back
models)
......
.
.
.
...
.
...
520-5

Front
seat,
removing
and
installing
...
.
.
.
..'
520-1



Rear
seat
cushion
and
backrest,

Manual
Front
Seat
Assembly
.............
520-3



removing
and
installing

fold-downsean
back
models
(



)
..
.
.
..
..
.
...
520-5
Power
Fronf
Seat
Assembly
..
.
.....
.
.
.
.
.
;
520-4



Rear
seat
backrest
side
section,

REAR
SEATS
.
.
.
.
.
.
.
.
.
............
.
...
520-5



removing
and
installing

(fold-down
seat
back
models)
..
.
.....
.
..
.520-6

4
.
Remove
plastic
caps
from
front
mounting
nuts,
and

then
remove
mounting
nuts
.
See
Fig
.
2
.

WARNING
-

Deactivate
front
seat
belt
lock
tensioners
before
proceeding
to
next
step
.
See720
Seat
Belts
.

NOTE-

Use
a
blanket
to
protect
door
sill
from
scuffing
bysean
rail
during
seatremoval
.

FRONT
SEA
TS

600-2



ELECTRICAL
SYSTEM-GENERAL

CAUTION
-

"
Always
turn
off
the
engine
and
disconnect
the

negative
()
cable
from
the
batterybefore
remov-

ing
any
electrical
components
.
Disconnecting
the

battery
may
erase
fault
code(s)
stored
in
control

module
memory
.
Check
for
fault
codes
using
spe-
cial
BMW
diagnostic
equipment
.

"
Prior
to
disconnecting
the
battery,
read
the
bat-

tery
disconnection
cautions
given
at
the
front
of

this
manual
onpage
viii
.

"
Connect
and
disconnect
ignition
system
wires,
multiple
connectors,
and
ignition
test
equipment
leads
only
while
the
ignition
is
off
.

"
Do
not
disconnect
the
battery
with
engine
run-

ning
.

"
Do
not
quick-charge
the
battery
(for
boost
start-
ing)
for
longer
than
one
minute,
and
do
not
ex-
ceed
16
.5
volts
at
the
battery
with
the
boosting
cables
attached
.
Wait
at
feast
one
minute
before
boosting
the
battery
a
second
time
.

"
Do
not
usea
test
famp
that
has
a
normal
incan-

descent
bulb
to
test
circuits
contafning
electronic
components
.
The
high
electrical
consumptionof
these
test
lamps
may
damage
the
components
.

"
Do
not
use
an
analog
meter
.
Use
onfy
a
digital
multimeter
.

"
Many
of
the
solid-state
modules
are
static
sensi-
tive
.
Static
discharge
will
permanently
damage
them
.
Always
handle
the
modules
using
proper
static
prevention
equipment
and
techniques
.

"
To
avoid
damaging
harness
connectors
or
relay
panel
sockets,
use
jumper
wires
with
flat-blade
connectors
that
are
the
same
size
as
the
connec-
tor
or
relay
terminals
.

"
Always
switch
a
digital
multimeter
to
the
appropri-
ate
function
and
range
before
making
test
con-
nections
.

"
Do
not
tryto
start
the
engine
of
a
carwhich
has
been
heated
above176°F
(80°C),
(for
example,
in
a
paint
dryingbooth)
.
Allow
it
to
cool
to
normal
temperature
.

"
Disconnect
the
battery
before
dolng
any
electric
welding
on
the
car
.

"
Do
not
wash
the
engine
while
it
is
runnfng,
or
any-
time
the
ignition
is
switched
on
.

WIRING
DIAGRAMS

Electrical
Test
Equipment

Many
of
the
electrical
tests
described
in
this
manual
call
for

measuring
voltage,
currentorresistanceusing
a
digital
multi-

meter
(DMM)
.
Digital
meters
are
preferred
for
precise
mea-

surements
and
for
electronics
work
because
they
are
generally
more
accuratethan
analog
meters
.
The
numerical

display
is
alsoless
likely
to
be
misread,
since
there
is
no
nee-

dle
position
to
be
misinterpreted
by
reading
at
an
angle
.

An
LED
test
light
is
a
safe,
inexpensive
tool
that
can
be
used

to
perform
many
simple
electrical
tests
that
would
otherwise

require
a
digital
multimeter
.
The
LED
indicates
when
voltage

is
present
between
anytwo
test-points
in
a
circuit
.

CA
UTION-

"
Choose
test
equipment
carefully
.
Use
a
digital

multimeter
with
at
leadt
10
megaohm
input
im-

pedance,or
an
LED
test
light
.
An
analog
meter
(swing-need1e)
ora
test
light
with
a
normal
incan-
descent
bulb
may
draw
enough
current
to
dam-
age
sensitive
electronic
components
.

"
An
ohmmeter
must
not
beused
to
measure
resis-
tance
on
solidstate
components
suchas
controlunits
or
time
delay
relays
.

"
Always
disconnect
the
battery
before
making
re-

sístance
(ohm)
measurements
on
the
circuit
.

WIRING
DIAGRAMS

The
wiring
diagrams
shown
in
Electrical
Wiring
Diagrams

have
been
specially
designed
to
enable
quick
and
efficientdi-

agnosis
and
troubleshooting
of
electrical
malfunctions
.

Wiring
Codes
and
Abbreviations

A
lot
of
information
is
included
in
each
wiring
diagram
if
you
know
how
to
read
them
.
Wire
colors
in
the
diagrams
are
ab-

breviated
.
Combined
color
codes
indicate
a
multi-colored
wire
.
For
example
the
code
BLU/RED
indicates
a
Blue
wire

with
a
Red
stripe
.

Many
electrical
components,
connectors,
fuses,
and

ground
locations
are
identified
using
a
unique
number
.
Each

of
there
numbers
corresponds
to
a
particular
part
in
the
circuit
commonly
found
in
Electrical
Wiring
Diagrams
.

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

650-2
RADIO

"
A
320-watt
Harmon-Kardon
ten
speaker
system,
including



RADIO
AND
SPEAKER
SERVICE
a
separate
high
power
multi-channel
audio
amplifier
and
two
sub-woofers
.
In
this
system,
thebass
and
volume
out-

puts
from
the
selected
audiosource
automatically
com-



Radio,
removing
and
installing

pensate
for
vehicle
speed,
making
constant
volume

adjustments
unnecessary
.
An
additional
feature
ofthis



CAUTION-
sound
system
is
the
ability
to
switch
from
normal
left-right



"
Before
beginning
work
on
the
radio
or
sound
stereo
into
Spatial
Enhancement
Mode,
which
produces
a



system,
verify
that
the
radio
is
an
original
equip-
fuller,
rounder
sound
.
See
Fig
.
3
.



ment
BMW
radio
and
that
thewiring
harness
has
not
been
modified
.
TheE36
radio
is
also
equipped
with
a
built-in
anti-theft
sys-

tem
.
lf
power
is
removed
from
the
radio
circuitry
by
removing

the
radio
electrical
connectors,
or
by
disconnecting
the
bat-
tery,
the
radio
is
rendered
inoperative
.
The
radio
is
not
perma-

nently
damaged,
and
proper
operation
can
be
restored
by

entering
the
radio
anti-theft
code
.

Fig
.
3
.
Ten
speaker
sound
system
.

RADIO
AND
SPEAKER
SERVICE

"
Servicing
of
aftermarket
sound
equipment
should
be
referredto
an
authorized
agent
of
the
equip-
ment's
manufacturer
.

"
Do
not
remove
radio
or
disconnect
the
batterywithout
first
obtaining
the
anti-theft
code
.

1.
Carefully
pry
open
small
square
covers
at
left
and
right

sides
of
radio
.

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

GENERAL

This
section
contains
wiring
diagrams
for
1992
through

1998
BMW
3
Series
models
.

WARNING
-

On
cars
equipped
with
airbags,
special
precautions
apply
to
any
electrical
testing
or
repair
.
The
airbag
unit
is
an
explosive
device
and
must
be
handled
with
exterme
care
.
Before
starting
any
work
onan
airbag
equipped
car,
refer
to
the
warnings
and
cau-
tions
in
720
Seatbelts
and
721
Airbag
Systems
(SRS)
.

NOTE-

The
"



gear
position/neutral
safetyswitch
is
also
some-
timesreferred
to
as
the
automatic
transmission
range
switch
.

"
The
EWS
11
system
is
also
sometimes
referred
to
as
the
Driveaway
Protection
System
or
the
electronic
im-
mobilization
system
.

ELECTRICAL
WIRING
DIAGRAMS



ELE-1

Electrical
Wiring
Diagrams

GENERAL
.
.
.
.
.
.
.
.
.
................
.
.
.
ELE-1



Horns



.....
.
.....
.
.
.
....
.
.
.
.
.
...
.
.
ELE-153

Instrument
Panel
.
.
.
.
.
.
..............
ELE-165

ELECTRICAL
WIRING
DIAGRAMS
...
.
.
.
ELE-2



Interior
Lights/Illumination
.............
ELE-211

ABS



..............
.
.
.
.....
.
.....
ELE-117



Lumbar
Control
.
....................
ELE-247

ABS/AST
.............
.
.
.
...
.
.
.
.....
ELE-120



On-Board
Computer
..................
ELE-173

Airbag
(Supplemental
Restraint
System)
..
ELE-140



Park
Ventilation
.
.
.
...........
.
...
.
..
ELE-139

Air
Conditioning
and
Heating
.
.
.
.
.
.
.....
ELE-129



Power
Distribution
......
.
...
.
.
.
.
.
.
.
...
.
ELE-2

Anti-Theft
(Alpine)
..........
.
.
.
...
.
...
ELE-144



Power
Door
Locks
.
.
......
.
.
.
.
.
.
.
.
.
..
ELE-226

Anti-Theft
(EWS
II)
.
........
.
.
.
...
.
...
ELE-150



Power
Mirrors
...
.
.
.
......
.
.
.
.
.
.
.
.
.
..
ELE-241

Body
Computer
Module
.....
.
.....
.
...
ELE-176



Power
Seats
......
.
......
.
.
.
...
.
.
.
..
ELE-243

Charging
System



.
.
................
.
.
.
ELE-67



Power
Sunroof
.
.
.
.
.
.
.
...............
ELE-248

Convertible
Top
.
.
.
.
................
.
.
ELE-253



Power
Windows
.
.
.
.
.
.
.....
.
.........
ELE-231

Cruise
Control
..
.
.
.
...........
.
....
.
.
ELE-112



Radio/Cassette/CD/Speakers
..........
ELE-255

Data
Link
Connector
................
.
.
.
ELE-86



Rear
Window
Defogger
...............
ELE-160

Engine
Cooling
.......
.
.......
.
....
.
.
.
ELE-94



Shift
Interlock
.
.
.
.
.
.
.
.
...............
ELE-110

Engine
Management
...
.
.......
.
....
.
.
.
ELE-70



Starting
....
.
.
.
.
.
...
.
................
ELE-63

Exterior
Lights
........
.
.
.
.
.
.
.
.
.
......
ELE-194



Transmission
Electronics
.
..............
ELE-96
Ground
Distribution
....
.
.
.
.
.
.
.
.
.
.......
ELE-35



Warning
System
:
Chimes
.............
ELE-178

Headlights/Foglights
...
.
.
.
.
.
.
.
.
.
......
ELE-180



Wiper/Washer
.
.....
.
...............
ELE-155

Heated
Seats
........
.
.
.
.
.
.
.
.
.
......
ELE-245

ELECTRICAL
COMPONENT
LOCATIONS

Relayand
fuse
positions,
ground
locations
...........
.
.
.
.
.
.
.
.
.
................
seeRepair
Group
610

CAUTION-

Always
switchthe
ignition
off
and
disconnect
the
negative
(-)
battery
cablebefore
removing
any
electrical
components
.

"
Prior
to
disconnecting
the
battery,
read
the
bat-tery
disconnection
cautions
given
at
the
front
of
this
manual
on
page
viii
.

"
Connect
and
disconnect
ignition
system
wires,
multiple
connectors
and
ignition
test
equipment
leads
only
while
ignition
is
switched
off
.

-Always
switch
a
test
meter
to
the
appropiate
func-
tion
and
range
before
making
test
connections
.

"
All-Season
Traction
(AST)
is
also
referred
to
as
ASC
or
ASC+T
.

GENERAL