1997 BMW 328i starter circuit

515-8



CENTRAL
LOCKING
AND
ANTI-THEFT

Central
Body
Electronics
(ZKE
IV)



Electronic
Immobilization
System
(EWS)

Beginning
withvehicles
produced
9193
(model
year
1994),



The
electronic
anti-theft
system
known
as
EWS
was
first
in-

the
centrallocking
system
was
integrated
with
sunroof
and



troduced
in
January
1994
.
The
early
version
of
the
system

window
closure
into
the
Central
Body
Electronics
(ZKE
IV)



uses
a
starting
inhibition
module
to
interrupt
the
ignition,
the

(generation
four)
system
.
The
control
module
for
this
system



fuel
injection
and
the
starter
motor
.
This
system
is
activated

ís
mounted
in
front
of
the
glove
compartment
.



and
deactivated
by
the
centrallockíng
system
.
The
control

module
for
the
system
is
installed
under
the
left
side
of
the

Inthis
system
two
microswítches
are
operated
viathe
door



dashboard
.

lock
cylinder
at
both
front
doors
.
Turning
the
key
approximate-

ly
45°
(position
1)
operates
the
door
locking
microswitch
and



Startingwith
modeis
built
since
January
1995,
E36
cars

activates
the
alarm
system
.
Holding
the
key
in
thatposition



come
equipped
with
a
sophisticated
coded
electronic
immobi

also
closes
any
open
windows
and
the
sunroof
.



lization
system
called
EWS
II
.
Foraschematic
of
the
system,

refer
to
Fig
.
21
.

Turning
the
key
approximately
45°
in
the
opposite
direction

through
position
0
actuates
theunlocking
microswitch
and
de-

activates
the
alarm
system
(position
2)
.
See
Fig
.
20
.
NOTE
-

The
EWS
11
system
is
also
sometimes
referred
to
as
the

Driveaway
Protection
System
or
the
electronic
immobi-
lization
system
.

On
EWS
II
equipped
cars,
the
ignition
key
is
embedded
with

a
computer
chip
and
permanently
encoded
.
A
primary
code
is

programmed
into
the
keyand
finto
the
vehicle
itself
.
A
second-

ary
code
is
changed
every
time
the
vehicle
is
started
.
If
thekey

code
and
EWS
II
control
module
code
do
notmatch,
the
en-

gine
management
control
module
and
the
starter
are
dis-

abled
.
EWS
II
ignition
keyscannot
be
duplicated
.

The
system
is
designed
to
have
up
to
ten
keys
and
only
an

authorized
BMW
dealer
can
provide
replacement
keys
.
j
NOTE-
0011762a



ft
is
possible
to
damage
the
electronic
circuítry
in
the
Fig
.
20
.
ZKE
IV
door
lock
cylinder
positions
.



key,
rendering
if
unusable
.
In
that
case,
a
new
key

shouldbe
purchased
and
initialized
byan
authorized
BMW
dealer
.

LOCKING
SYSTEM
AND
ELECTRONIC
IMM081LIZATION

600
Electrical
System-General

GENERAL
.
...........
.
.
.
.
.
.
.
.
.
...
.
...
600-1

Voltage
and
Polarity
........
.
.
.
.
.
.
.
.....
600-1

Ming,
Fuses
and
Relays
............
.
.
.
.
600-1

Electrical
System
Safety
Precautions
...
.
.
.
.
600-1

Electrical
Test
Equipment
.....
.
.
.
....
.
.
.
.
600-2

WIRING
DIAGRAMS
..
.
.
.
.
.
.
.
.
.
........
600-2

Ming
Codes
and
Abbreviations
..
.
...
.
....
600-2

ELECTRICAL
TROUBLESHOOTING
..
.
..
600-3

Voltage
and
Voltage
Drops
..........
.
.
.
.
.
600-4

GENERAL



Electrical
System
Safety
Precautions

A
brief
description
of
the
principal
parts
of
the
electrical
sys-
tem
is
presented
here
.
Also
covered
here
are
basic
electrical
system
troubleshooting
tips
.

Voltage
and
Polarity

The
vehicle
electrical
system
is
a
12-volt
direct
current
(DC)
negative-ground
system
.
A
voltage
regulator
controls
system
voltage
at
approximately
the
12-volt
rating
of
the
battery
.
Al¡
circuits
are
grounded
by
direct
or
indirect
connection
to
the

negative
(-)
terminal
of
the
battery
.
A
number
of
ground
con-

nections
throughout
the
car
connect
the
wiring
harness
to

chassis
ground
.
These
circuits
are
completedby
the
battery

cable
or
ground
strap
between
the
body
and
the
battery
nega-

tive
(-)
terminal
.

Wiring,
Fuses
and
Relays

Nearly
all
parts
of
the
wiring
harnessconnect
to
compo-

nents
of
the
electrical
system
with
keyed,
push-on
connectors

that
lock
into
place
.
Notable
exceptions
arethe
heavy
battery

cables
and
the
starter
wiring
.
The
wiring
is
color-coded
for
cir-

cuitidentification
.

With
theexception
of
the
battery
charging
system,
most

electrical
power
is
routed
from
the
ignition
switch
or
the
bat-
tery
through
the
main
fuse/relay
panel,
located
in
¡he
left
rear

comer
of
the
engine
compartment
.
Fuses
are
color
coded
to

indicate
current
capacities
.

The
relays
and
control
units/modules
are
mounted
in
vari-

ous
places
throughout
the
vehicle
.
See610
Electrical
Com-

ponent
Locations
.

ELECTRICAL
SYSTEM-GENERAL
600-1

Voltage,
measuring
.
.
.
................
.
.
600-4

Voltage
drop,
testing
.
.
.....
.
.....
.
......
600-4

Continuity,
checking
..
.
...
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
600-5
Short
Circuits
.
.
.
.
.
.
.
.
.....
.
...
.
.
.
.
.
.
.
.
.
600-5

Short
circuit,
testing
with
ohmmete'r
.
.
.
.
.
.
.
.
.
600-6

Short
circuit,
testing
with
voitmeter
.
.
.
.
.
.
.
.
.
600-6

TABLES
a
.
Terminal
and
Circuit
Numbers
..............
..
.600-3
Please
read
the
following
warnings
and
cautions
before
do-
ing
any
work
on
your
electrical
system
.

WARNING
-

"
The
cars
covered
by
this
manual
are
equipped
with
aSupplemental
Restraint
System
(SRS)
that
automatically
deploys
one
or
more
airbags
.
Each
airbag
unit
houses
an
explosive
powerful
charge
.
Any
work
involving
the
SRS
system
should
only
be
performed
byan
authorized
BMW
dealer
.
Making
repairs
without
the
proper
knowledge
and
special
test
equipment
may
cause
serious
per-
sonal
injury
.
See
721
Airbag
System
(SRS)
.

"
The
ignition
system
of
the
car
operates
at
lethal
voltages
.
People
with
pacemakers
or
weak
hearts
should
not
expose
themselves
to
the
ignition
sys-
tem
.
Extra
caution
mustbe
taken
when
working
on
the
ignition
system
or
when
servicing
theen-
gine
while
it
is
runningor
the
key
is
on
.
See
120
Ignition
System
for
additional
ignition
system
warnings
and
cautions
.

"
Before
operating
the
starter
without
starting
the
engine
(as
when
making
a
compressfon
test),
dis-
able
the
ignition
system
as
described
in
120
Igni-
tion
System
.

"
Keep
hands,
clothing
and
other
objects
clear
of
the
electric
radiator
coollng
fan
when
working
on
a
warm
engine
.
The
fan
may
start
at
any
tíme,
even
when
the
ignition
is
switched
off
.

GENERAL

NOTE
-

Sometimes
the
color
of
en
installed
wire
may
be
differ-
ent
than
the
one
on
the
wiring
diagram
.
Don't
be
con-
cerned
.
Just
be
sure
lo
confirm
that
the
wire
connects
lo
the
proper
terminals
.

Wire
color
codes

"
BLU
.........
.
..
..
...
.
.................
Blue

"
BRN
....:....
.
..
..
...
..
...............
Brown

"
YEL
.........
.
..
..
...................
.Yellow

"
GRN
.........
.
..
..
...
.
................
creen

"
G
RY
.......
.
.
.
..
..
.....................
G
ray

"
ORG
.........
.
..
..
...
.
..............
.Orange

"
RED
......
...
.
.
..
.....................
.Red

"
BLK
.........
.
..
..
...
.
................
Black

"
VIO
..........
.
..
...
..
..
.......
.
.......
Violet

"
WHT
.........
.
.
....
.
...
:..............
White

Table
a
.
Terminal
and
Circuit
Numbers

Number



1
Circuít
description

1



j
Low
voltage
switched
terminal
of
coi¡

4



1
High
voltage
center
termina¡
of
coi¡

+x



Originates
atignition
switch
.
Supplies
powerwhen
the
ignition
switch
is
in
the
PARK,
RUN,
or
START
position

15



Originates
atignition
switch
.
Supplies
powerwhen
ignition
switch
is
in
RUN
or
START
position

30



Battery
positive
(+)
voltage
.
Supplies
power
whenever
battery
is
connected
.
(Not
dependent
on
ignition
switch
position,
unfused)

31



1
Ground,
battery
negative
(-)
terminal

50



Supplies
power
from
battery
to
starter
solenoid
when
ignition
switch
isin
START
position
only

+54



Originates
atignition
switch
.
Supplies
power
when
ignition
switch
isin
the
RUN
position
only

85



1
Ground
side
(-)
ofrelay
coil

86



1
Power-in
side
(+)
ofrelay
coil

87



1
Relay
actuatedcontact

D



Alternator
warning
light
and
field
energizing
circuit

ELECTRICAL
SYSTEM-GENERAL
600-
3

Additional
abbreviations
shown
in
the
wiring
diagrams
are

given
below
.

Abbreviations

"
ABS
........
.
...
.
...
.
..........
antilock
brakes

"
A/C
........
.
...
..
..
.
.........
.airconditioning

"
AST/ASC+T
.......
...
.
.
.......
al¡
season
traction

"
CONV
.......
.
.
...
.................
convertible

"
DME
........
.
.
...
.......
digital
motor
electronics

"
ECM



.......
.
...
..
..
.
..
electronic
control
module

"
EWS/EWS
II
......
...
.
.
coded
driveaway
protection

"
SRS
........
.
supplemental
restraint
system-airbag

"
TCM
........
.
..
....
.
transmission
control
module

"
ZKE
(94-98
models)
..
..
.
...
central
body
electronics

"
ZVM
(92-93
models)
...
.
.
..
.
.......
central
locking

ELECTRICAL
TROUBLESHOOTING

Most
terminals
are
identified
by
numbers
on
the
compo-

nents
and
harness
connectors
.
The
terminal
numbers
for
ma-



Four
things
are
required
for
current
toflow
in
any
electrical

jor
electrical
connections
are
shown
in
the
diagrams
.
Though



circuit
:
a
voltagesource,
wires
or
connections
to
transport
the

many
terminal
numbers
appear
only
once,
severa¡other
num-



voltage,
a
load
or
device
that
uses
the
electricity,
and
a
con-
bers
appear
in
numerous
places
throughout
the
electrical
sys-



nection
to
ground
.
Most
problemscanbefound
using
a
digital

tem
and
identify
certain
types
ofcircuits
.
Some
of
the
most



multimeter
(volt/ohm/amp
meter)to
check
for
voltage
supply,

common
circuit
numbers
are
listed
below
in
Table
a
.



for
breaks
in
the
wiring
(infinite
resistance/no
continuity),
orfor

a
path
to
ground
that
completesthe
circuit
.

Electric
current
is
logical
in
its
flow,
always
moving
from
the

voltage
sourcetoward
ground
.
Electricalfaults
can
usually
be

located
through
a
process
of
elimination
.
When
troubleshoot-

ing
a
complex
circuit,
separate
the
circuit
into
smaller
parts
.

The
general
testsoutlined
below
may
be
helpful
in
finding

electrical
problems
.
The
information
is
most
helpful
when

used
with
the
wiring
diagrams
.

Be
sure
to
analyze
the
problem
.
Use
the
wiring
diagrams
to

determine
the
most
likely
cause
.
Getan
understanding
of
how

the
circuit
works
by
following
the
circuit
from
groundback
to

the
power
source
.

When
making
test
connections
at
connectors
andcompo-

nents,
use
care
to
avoidspreading
or
damaging
the
connec-

tors
or
terminals
.
Some
tests
may
require
jumper
wires
to

bypass
components
or
connections
in
the
wiring
harness
.

When
connecting
jumper
wires,
use
bladeconnectors
at
the

wire
ends
that
match
the
size
of
the
terminal
being
tested
.
The

small
interna¡
contacts
are
easily
spread
apart,
and
this
can

cause
intermittent
or
faultyconnections
that
can
leadto
more

problems
.

ELECTRICAL
TROUBLESHOOTING

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
.

WARNING

Your
common
sense,
good
judge-

ment,
and
general
alertness
are
cru-

cial
to
safe
and
successful
service

work
.
Before
attempting
any
work
on

your
BMW,
read
the
warnings
and

cautions
on
page
vi¡
and
the
copyright
page
at
the
front
of
the
manual
.
Review
these
warnings
and
cautions
each
time
youprepare
to
work
on
your
BMW
.
Please
also
read
any
warnings
and
cautions
that
accom-

pany
the
procedures
in
the
manual
.

A

ABS
(anti-lock
brakes)

See
Brakes
Accelerator
and
throttle
linkage
See
Maintenance
program
Air
conditioning
general
information
640-1
air
distribution
motor,
replacing
(rotary

knob)
640-10
air
distribution
motors
640-9

blower
motor,
removing/installing

640-1blower
motor
resistor
pack,
replacing
640-3
compressor,
replacing
640-12
compressor
clutch
640-13
condenser,
replacing
640-14
control
head
640-7
removing/installing
(digital
-display)

640-8
removing/installing
(rotary
knob)

640-7
control
module
removing/installing
(digital-display)
640-8
removing/installing
(rotary
knob)
640-8
evaporator,
removinglinstalling

640-17
evaporator
temperature
sensor,

replacing
640-17

expansion
valve,
removing/installing

640-16
microfilter,
replacing
640-18
receiverldrier,
replacing
640-15
sensor
fan
forinterior
temperature,

replacing
640-9
warnings
and
cautions
640-11

Air
distribution
(flap)
motor

See
Air
conditioning
See
also
Heating
Air
filter
See
Maintenanceprogram

Airbag
system
(SRS)
general
information
721-1

contact
ring,
replacing
721-3

driver
side
airbag,removing/installing

721-5
front
crash
sensor,
replacing
721-4

front
side-impact
airbag,
removing/
installing
721-7

front
side-impact
airbag
crash
sensor,

removing/installing
721-5

passenger
side
airbag,
removing/

installing
721-6
sensors
and
electronics
721-1

SRS
warning
light
and
fault
display

721-2
systems
721-1
ZAE
control
module,
replacing
721-5

Alarm
system
See
Central
locking
and
anti-theft

Alternator
See
Battery,
starter,
alternator

Anti-freeze
(Engine
coolant)

See
Maintenance
program

Anti-theft
See
Central
lockíng
and
anti-theft

AST
(Al¡
season
traction)
300-4

ATF
(Automatic
transmission
fluid)

See
Automatic
transmission

Automatic
transmission

See
alsoTransmission-general
general
information
240-1

ATF,draining
and
filling
240-2

ATF
leve¡,
checking
240-1
transmission
removaland
ínstallation

240-4
transmission,
removinglinstalling
240-4
transmission
service
240-1

Auxiliary
fan
See
Cooling
system
Axle
joint
See
Maintenance
program

B

Back-up
light
switch
See
Manual
transmission
Balljoint
See
Front
suspension
Battery
See
Battery,
starter,
alternator

Battery,
starter,
alternator
See
also
Maintenance
program
general
information
121-1

alternator,
removing/installing
(4-
cylinder
engine)
121-5
alternator,
removinglinstalling
(6-
cylinder
engine)
121-6
alternator
brushes,
inspecting/
replacing
121-7
alternator
service
121-4
batterycharging
121-4
battery
load
voltage
test
121-4

batteryopen-circuit
voltage
test
121-4

battery
service
121-3

INDEX
1

Battery,
starter,
alternator
(cont
.)
battery
testing
121-3
charging
system
quick
check121-2
charging
system
troubleshooting
121-
2
hydrometer
testing
121-3
solenoid
switch,
removinglinstalling
121-10
starter
service
121-7
starter
troubleshooting
121-7
starter,
removing/installing(4-cylinder
engine)
121-8
starter,
removing/installing(6-cylinder

engine
with
automatic
transmission)

121-9
starter,
removing/installing
(6-cylinder
engine
with
manual
transmission)
121-8
static
current
draw,
checking
121-2
voltage
regulator,
removing/installing
121-6
Bearing,
wheel
See
Front
suspension
or
Rear

suspension
Blowermotor
See
Air
conditioning
See
also
Heatíng
BMW
emblem
See
Exterior
trim,
bumpers
Body-general
general
information
400-1

body
assembly
400-1
central
body
electronics
400-4
convertible
models
400-2
coupe
models
400-2
electronic
immobilizatíon
system
400-
4
exterior
and
aerodynamics
400-2

heating
afhdair
conditioning
400-5

instruments
and
controls
400-4
interior
equipment
400-3
seats
and
seatbelts
400-3
Body
side
molding
See
Exterior
trim,
bumpers

Brake
fluid
See
Maintenance
program

Brakes
general
information
340-1
antilock
brake
system
(ABS)
340-11
inspection
340-12
wheelspeed
sensors,
replacing

340-12
bleeding
brakes
340-3
brake
booster,
removinglinstalling
340-8
brake
caliper,
removing/installing

340-6
brake
pads,
calipers,
and
rotors
340-3

brake
pads,
replacing
340-4
brake
rotor,
removing/installing
340-7
master
cylinder,
removing/installing

340-7
parking
brake
340-10
adjusting
340-10
.
cable,
replacing
340-11
shoes,
removinglinstalling
340-11