1997 BMW 318i engine compartment

340-
8
BRAKES

Fig
.
10
.
Brake
fluid
linesat
master
cylinder
(arrows)
.

6
.
If
fluid
reservoir
was
removed,
install
it
carefully
using
new
sealing
grommets
.

7
.
Mount
master
cylinder
to
brake
booster
using
a
new
0-
ring
and
new
self-locking
nuts
.

CAUTION-

Use
cave
not
to
over-torque
the
master
cylinder
mounting
nuts
.
This
could
damage
the
brake
booster
and
prevent
proper
vacuum
build-up
.

0012164

8
.
Connect
all
brake
fluid
lines
.
Connect
hydraulic
clutch
hose
to
brake
fluid
reservoir
.

9
.
Reconnect
fluid
leve¡
sender,
and
bleed
entire
brake
systemas
described
earlier
.

BRAKE
BOOSTER

BRAKE
BOOSTER

The
brake
booster
is
mounted
to
the
bulkhead
on
the
driver
sideofthe
engine
compartment,
directly
behind
the
brake
master
cylinder
.
See
Fig
.
11
.

0015225
Fig
.
11
.
Brake
booster
(arrow)
.
A
is
vacuum
hose
from
intake
mani-
fold
.
B
is
one-way
valve
.
Intake
manifold
vacuum
acts
ona
large
diaphragm
in
the
brake
booster
to
reducebrake
pedal
effort
.

Brake
booster,
removing
and
installing

1
.
Disconnect
negative
(-)
cable
from
battery
.

CAUTION-

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

Tightening
Torque

"
Brake
master
cylinder
to



2
.
Using
a
clean
syringe,
empty
brake
(luid
reservoir
.

brake
booster
.....
..
.
..
.........
26
Nm
(18
ft-Ib)



WARNING-
"
Brake
fluid
hose
to
caliper
....
17-19
Nm
(13-14
ft-Ib)



Brake
fluid
is
highly
corroslve
and
dangerous
to
the
environment
.
Dispose
of
it
properly
.

3
.
Remove
brake
fluid
level
sender
connector
from
reser-
voir
cap
.

4
.
Disconnectbrake
fluid
lines
from
master
cylinder
.
Plug
openings
.

5
.
Disconnect
engine
vacuum
hose
from
brake
booster
.

6
.
Disconnect
ABS
electrical
connectors
.
Label
and
then

disconnect
brake
lines
from
hydraulic
brake
unit
.
Plug

openíngs
.
See
Fig
.
12
.

~
~
A
1/
B
'1v
C
~
F

lu
11
-ri
J
.

0013244
A
.
Right
front



F



Front
from
master
cylinder
B
.
Leftfront



R
.
Rear
from
master
cylinder
C
.
Rear

Fig
.
12
.
Brake
fluid
linesat
ABS
hydraulic
unit
.

WARNING
-

"
On
cars
with
All
Season
Traction
(AST),
special
BMW
service
equipment
is
required
to
properly
bleed
the
Antilock
Brake
System
(ABS)
.
Removal
of
the
ABS
hydraulic
unit
is
not
recommended
un-
less
this
equipment
is
available
.
For
safetyrea-
sons,
the
brake
system
on
cars
with
ABS
must

not
be
bled
using
the
procedures
described
inthis
repair
group
.

"
Do
not
mix
up
the
fluid
fines
at
the
ABS
hydraulic
unit
Label
all
connections
before
disconnecting
.

7
.
Remove
ABS
hydraulic
unit
from
engine
compartment
.

8
.
Working
inside
car,
remove
panel(s)
frombeneath

steering
column
to
access
pedal
assembly
.
See513
In-

terior
Trim
.

12
.
Make
sure
al¡
nuts,
fluid
couplings,
thread
bores
and

mating
surfaces
are
clean
.

BRAKES
340-
9

0011261

Fig
.
13
.
Brake
pedal
clevispin
and
retaining
clip
(A)
.
Brake
booster
mounting
nuts
shown
at
arrows
.

13
.
If
necessary,
mount
master
cylinder
to
vacuum
booster

using
a
new
O-ríng
and
newself-locking
nuts
.

CAUTION-

Do
not
over-torque
the
master
cylinder
mounting
bolts
.
This
could
damage
the
brake
booster
and
prevent
proper
vacuum
build-up
.

14
.
Installation
is
reverse
of
Rmoval
.

"
Bleed
brakes
as
described
earlier
.

"
Check
and,
if
necessary,
adjust
brake
light
switch

above
brake
pedal
.

Tightening
Torques

"
Brakemaster
cylinder
to

brake
booster
...........
.
..
..
...
26
Nm
(18
ft-Ib)

"
Brake
booster
to
bulkhead
.
.
..
..
...
22
Nm
(16
ft-Ib)

"
Brake
fluidline
to
master
cylinder
or

ABS
hydraulic
unit
.......
.
..
17-19
Nm
(13-14
ft-lb)
9
.
Remove
clip
and
clevis
pin
from
brake
booster
pushrod

and
disconnect
it
from
brakepedal
.
Remove
brake

booster
mounting
nuts
.
See
Fig
.
13
.
NOTE-

10
.
Working
in
engine
compartment,
remove
brake
booster



When
replacing
the
brake
booster
one-way
valve
or
together
with
master
cylinder
.



vacuum
hose,
install
the
valve
so
that
the
molded
arrow

is
pointing
toward
the
intake
manifold
.
Use
new
hose

11
.
If
booster
or
master
cylinder
O-ring
is
being
replaced,



clamps
.

disconnect
master
cylinder
from
brake
booster
.

BRAKE
BOOSTER

400-2
BODY-GENERAL

4-door
Sedan

Coupe

-
saas3
.7""

351
/



37
.3
O



I
x
`-193



267

o
oa

'3281
model
"M3
model

Convertible

BODYASSEMBLY

55
ass
.e
iss
""
-
66
.9
-

Fig
.
2
.



E36
body
dimensíons
.

BODY
ASSEMBLY

29
.4

29
4

The
BMW
3
Series
chassis
is
a
unibodydesign
constructed
ofhigh
strength
steel
.
Attaching
parts,
suchas
the
front
fend-
ers,
rear
quarter
panels,
doors,
trunk
lid
and
hood
are
also
constructed
of
steel
.

706
.31108
.7"



I
38
.5
174
.5

174
.5

O



oo

196
.3/106
.7'
"



35_5



1.
.
55
.9,566
".

106
.3/196
.7""



i.
358
-1745-

55
9/56
3'/56
6"
-
J

0013099

Windows
bonded
flush
to
the
body
and
the
guided
flow
of
cooling
air
into
the
engine
compartment
provide
a
good
coeffi-
cient
of
drag(CD)
.
TheE36
cars
have
a
CD
of
approximately
0
.30for
the
sedan
and
coupe
models,
and
0
.35
for
the
con-
vertible
models
:

The
exterior
panels
are
corrosion-resistant
zinc
coated

steel
.
The
front
fenders
are
bolted
on
and
easily
replaceabie
.
The
body
styles
of
E36
cars
coveredby
this
manual
arethe



See410
Fenders,
Engine
Hood
.
4-door
sedan,
2-door
coupe
and
convertible
.
Body
dimen-
sions
vary
slightly
betweenmodels
.
See
Fig
.
2
.



The
front
and
rear
bumpers
use
an
aluminum
framework
with
an
overlaid
high-impact,
deformable
plastic
cover
.
This
Exterior
and
Aerodynamics



bumper
system
keeps
damage
to
a
minimum
in
head-on
colli-
sions
of
up
to
10
m
.p
.h
.
(15
km/h)
.
See
510
Exterior
Trim,
TheE36
can
be
immediatelyrecognized
asa
typical
BMW
.



Bumpers
.
With
its
traditionalstyling
features,
suchas
the
BMW
kidney
grille,
circular
headlights
behind
a
glass
cover
(for
reasons
of
streamliníng),
and
the
"kick"
in
the
rearmost
roof
pillar
(C-pil-
lar)
.

Ambient
temperaturelclock

MÍM
Aa
.Mi}rm
-Mil"
IMua~naa~u~itacar
"
za
.~

Central
Body
Electronics

0013028

Fig
.
4
.



Different
versionsof
Multi-information
Display(MID)
installed
in
E36
cars
.

The
E36
cars
are
equipped
with
a
sophisticated
centralized

body
electric/electronics
plan
.
The
system
is
self-diagnostic

and
incorporates
many
functions
into
a
single
control
module
.

The
consolidation
of
several
systems
into
a
single
control

module
minimizes
power
requirements
and
the
incorporation

of
the
diagnostic
link
results
in
more
efficient
and
accurate

troubleshooting
.

Self-diagnostic
codes
are
accessible
electronically
through

the
data-link
connector
in
the
engine
compartment
.
See610

Electrical
Component
Locations
.

BODY-GENERAL
400-
5

Two
versions
of
central
body
electronics
are
used
depend-

ing
on
model
year
.

1992
and
1993
models
are
equipped
with
a
central
locking

module
(ZVM)
which
incorporates
control
of
the
following
sys-

tems
:

"Interiorlighting
"
Central
locking
with
double
lock
feature

"
Output
relays
for
powerwindows
and
sunroof

"
Electronic
power
protection

E36
cars
since
the
1994
model
year
are
equipped
with
ZKE

IV
.
This
is
an
electronic
comfort
and
convenience
system
that

includes
the
following
additional
features
:

"
One
touch
up/down
power
window
operation

"
Power
window
and
sunroof
closure
from
driver
or
pas-

sengerdoor
lock

"
Vehicle
locking
or
unlocking
from
the
trunk
lock
.

Other
features
of
the
system
are
discussed
in
515
Central

Locking
and
Anti-Theft
.

Electronic
Immobilization
System

Beginning
in
model
year
1994,
all
E36
vehicles
incorporate

adriveaway
protection
system
regardless
of
whether
the
vehi-

cle
is
equipped
with
a
BMW
Alarm
System
or
an
On-Board

computer
.
Two
types
of
factory
systems
were
installed,
de-
pending
on
vehicle
production
date
.

On
the
early
system
(model
year
1994
up
to
January
1995),

the
ignition
and
fuel
injection
functions
are
disabled
whenever

the
vehicle
is
locked
in
the
double
lock
mode
.
This
is
referred

lo
as
EWS
or
EWS
I
.

Beginning
in
January
1995,
the
driveaway
protection
sys-

tem
was
upgraded
to
a
more
sophisticated
system,
called

EWS
II
.
This
system
uses
a
wireless
communication
link
be-

tween
a
transponder
chip
in
the
ignition
keyand
the
ring
an-

tenna
surrounding
the
ignition
switch
.
The
EWS
II
control

module
blocksthe
starting
of
the
vehicle
unlessthe
correct

coded
ignition
key
is
used
.

For
further
information
about
drive
away
protection
sys-

tems,
see
515
Central
Locking
and
Anti-Theft
.

INTERIOR
EQUIPMENT

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

610-4



ELECTRICAL
COMPONENT
LOCATIONS

--J
L
Windshield
washertank
&
pump

Fig
.
7
.



E36
engine
compartment
layout
.
M42
engine
compartment
shown
.

-,x
0013204

Fig
.
8
.
Control
modules
under
right
sideof
dash
.
Glove
compart-
ment
has
been
removed
.
For
module
identification,
see
Fig
.
9
.

COMPONENT
LOCATIONS

RSP
'I



4

ABS



Main
engine



Power
hydraulic
harness
distribution
control
unit



connector
I



box
oe

1
.
SRS
(Airbag)
control
module
(through
1993)
2
.
ABS/ASC+T
control
module
(as
applicable)
3
.
Central
locking
module
(through
1993)
4
.
Anti-theft
alarm
module
or
ZKE
IV
control
module
(from
1994)5
.
Rear
window
blower
relay
(convertible
models)6
.
Horn
relay
7
.
Wiper/washer
module
8
.
Rear
power
window
relay
(four-door
models)9
.
Luggage
compartment
lid
lock
relay
(convertible)
10
.
Cruise
control
module
EWS
II
control
module
(from
Jan
.
1995)
RSP
:
Right
splice
panel

0013215

Fig
.
9
.



Identificationof
control
modules
under
right
side
of
dash
.
Module
utilízation
varies
byyear
andmodel

1
.
Heater
valves
2
.
ABS
pedal
travel
sensor3
.
ABS
pump

Fig
.
10
.
Left
rear
of
engine
compartment
.

4
.
Main
engineharness
con-
nector
5
.
Power
distribution
box

ELECTRICAL
COMPONENT
LOCATIONS
610-5

0013202
0013226

Fig
.
11
.
M42
engine
idie
speed
control
valve
(arrow)
beneath
intake
manifold

0012421

Fig
.
12
.
M44
engine
intake
air
temperature
(¡Al)
sensor
in
air
filter
housing

Fig
.
13
.
M50/S50U
S
engine
intake
air
temperature
(IAT)
sensor
(1)
and
throttle
position
sensor
(2)
.

301180

0012724

Fig
.
14
.
M52/S52U
S
engine
intake
air
temperature
(IAT)
sensor
in
bot-
tom
of
intake
manifold
(throttle
housing
shown
removed)
.

COMPONENT
LOCATIONS

Fig
.
19
.
M44
engine
coolant
temperature
(ECT)
sensor
(arrow)
.



Fig
.
22
.
Headlight
ground
at
left
frontof
engine
compartment
(arrow)
.

0012704

Fig
.
20
.
M52
engine
coolant
temperature
(ECT)
sensor
(A)
is
located
beneath
top
enginecover
(B)
and
crankcase
vent
hose
(C)
.

uu12700

Fig
.
21
.
M52
throttle
position
sensor
(A),
idle
speed
control
valve
(B),
and
secondary
air
pump
(C)
.

ELECTRICAL
COMPONENT
LOCATIONS



610-7

00119s4



0013131

uvijijo
Fig
.
23
.
Mainground
at
right
strut
tower
(A)
.
B
is
negative
jumper
con-
nection
.

COMPONENT
LOCA
TIONS