Cooling
System
Pressure
Test
If
the
engine
overheats
and
no
other
cooling
system
testsindicate
trouble,
the
radiator
may
have
some
pluggedpassag-
A
cooling
system
pressure
test
is
used
to
check
for
internal
es
that
are
restricting
coolant
flow
.
leaks
.
Some
of
the
common
sources
ofinternal
leaks
are
a
faulty
cylinder
head
gasket,
a
cracked
cylinder
head,
or
a
Temperature
Gauge
Quick
Check
cracked
cylinder
block
.
The
coolant
temperature
sensor
is
located
on
the
intake
To
doa
cooling
system
pressure
test,
a
special
pressure
manifold
(left)
side
of
the
cylinder
head,
under
the
intake
man-
tester
is
needed
.
ifold
runners
.
See
Fig
.
2
.
WARNING
-
At
normal
operating
temperature
-
the
cooling
sys-
tem
is
pressurized
.
Allow
the
system
to
cool
before
opening
.
Release
the
cap
slowly
to
allow
sale
re-
tease
of
pressure
.
With
the
engine
cold,instan
a
pressure
tester
to
the
expan-
sion
tank
.
Pressurize
thesystem
to
the
specification
listed
be-
low
.
Pressure
should
not
drop
more
than
0
.1
bar
(1
.45
psi)
for
at
leakt
two
minutes
.
If
the
pressure
drops
rapidly
and
there
is
no
sign
of
an
externa¡
leak,
the
cylinder
head
gasket
may
be
faulty
.
Considera
compression
test
as
described
in
100
En-
gine-General
.
The
screw-on
type
expansion
tank
cap
should
also
be
test-
ed
using
a
pressure
tester
and
the
correct
adapter
.
Cooling
System
Test
Pressure
"
Radiator
test
pressure
.........
.
1
.5
bar
(21
.75
psi)
"
Radiator
cap
test
pressure
..
.
........
2
bar
(29
psi)
CA
UTION-
Exceeding
the
speclfied
test
pressure
could
dam-
age
the
radiatoror
other
system
components
.
Carefully
inspect
the
radiator
cap
for
damage
.
Replace
a
faulty
cap
or
a
damaged
cap
gasket
.
Thermostat
Quick
Check
In
later
models,
the
ECT
sensor
and
the
gauge
sender
are
combined
into
one
sender
unit
.
For
wire
colors
refer
to
Table
a
.
To
check
if
the
thermostat
is
opening
and
coolant
is
circulat-
ing
through
the
radiator,
allow
a
cold
engine
to
reach
operat-
ing
temperature
(temperature
gauge
needieapproximately
centered)
.
Shut
off
engine
.
Feel
the
top
radiator
hose
.
If
the
hose
is
hot
to
the
touch,
the
coolant
is
probably
circulating
cor-
rectly
.
If
there
are
any
cool
areas
in
the
hose
or
radiator,
cool-
ant
flow
to
the
radiator
is
probably
restricted
.
Check
for
a
faulty
thermostat
or
aplugged
radiator
.
NOTE-
A
thermostat
that
is
stuck
open
will
cause
the
engine
to
warmup
slowly
and
run
belownormal
temperature
at
highway
speed
.
A
thermostat
that
is
stuck
closed
will
re-
strict
coolant
flow
to
the
radiator
and
cause
overheating
.
RADIATOR
AND
COOLING
SYSTEM
170-
3
U
.¡ig
.v
Fig
.
2
.
Temperature
gauge
sender
on
M44
engine
.
Temperature
gauge
sender
location
is
similar
on
al]
engines
.
In
early
models,
the
engine
coolant
temperature
(ECT)
sen-
sor
for
the
fuel
injection
and
the
coolant
temperature
gauge
sender
are
located
side
by
side
.
Table
a
.
Coolant
Temperature
Sensor
Wire
Colors
Function
Sensor
Terminal
Wire
colors
location
number
Two
sensors
:
Temperature
Rear
1
Brown/violet
gauge
sender
2
Brown/yellow
ECT
sensor
Front
1
Brown/red
2
Brown
or
Brown/black
One
sensor
:
Temperature
Dual
1
Brown/yellow
gauge
sender
sensor
2
Brown/violet
ECT
sensor
3
Brown/red
4
Brown/black
or
Grey/black
TROUBLESHOOTING
400-
4
BODY-GENERAL
INTERIOR
EQUIPMENT
E36
interiors
have
a
unique
character,
with
a
combínation
of
sporty
features
and
innovative
design
.
Al¡
body
versions
were
made
in
a
wide
choice
of
interior
and
exterior
colors
.
New
colors
with
matching
leather
and/or
fabric
upholstery
were
in-
troduced
for
each
model
year,
including
light-alloy
wheels
in
new
designs
.
Driving
comfort
is
enhanced
by
power
steering,
tilt
steering
wheel
(optional),
height-adjustable
front
seats,
and
electrical-
ly
adjustable
and
heated
rear-view
mirrors
.
Inside
thecar
there
are
reading
lights
at
four
seating
positions
.
Seats
and
Seat
Belts
NOTE-
Theseat
base
usedon
cars
with
pyrotechnic
seatbelt
Anatom¡cal
ly-correct
seats
are
constructed
from
polyure-
tensioners
is
not
interchangeable
with
the
earlier
seat
thane
foam
containing
areas
or
"zones"
of
different
firmness
.
base
.
The
seat
bases
have
steel
springs
for
added
support
and
strength
.
The
power
seats
are
provided
with
conveniently
lo-
Instruments
and
Controls
cated
switches
along
the
outside
edge
of
the
seat
.
Heated
seats
are
an
option
in
all
models
.
See
520
Seats
for
more
de-
Everything
in
the
interior
passenger
compartment
essential
tails
.
to
the
driver
is
logically
grouped
and
easy
to
reach
.
Al¡
instru-
ments
and
controls
havebeen
arranged
ergonomically
and
The
M3
sport
seat
is
shown
in
Fig
.
3
.
are
fully
integrated
into
the
overall
design
of
the
vehicle
.
Fig
.
3
.
M3
sport
seat
.
INTERIOR
EQUIPMENT
0013195
The
early
E36
cars
areequipped
with
a
single
(driver
side)
airbag
in
the
steering
wheel
.
Startingwith
the
1994
models,
a
dual
airbag
Supplemental
Restraint
System
has
been
stan-
dard
equipment
.
Side-impact
airbags
in
the
front
doors
are
op-
tional
in
1997
4-door
cars
and
standard
equipment
in
all
1998
models
.
Through
1996,
E36
seatbelts
were
equipped
with
BMW's
original-designspring
tensioners
.
In
1997,
the
seat
base
de-
sign
was
modified
to
accommodate
a
pyrotechnic
(explosive
charge)
seatbelt
tensioner
.
Both
types
of
tensioners
arede-
signed
to
automatically
tension
the
belts
by
about2
inches(55
mm)
in
the
event
of
a
collision
.
The
padded
dashboard
houses
the
instrument
cluster
and
the
ventilation
and
heating
system
.
The
instrument
cluster
uses
large
easy-to-read
analog
instruments
and
is
removable
as
a
unit
without
removing
the
dashboard
.
The
Service
Inter-
val
Indicator
(SII)
will
remind
the
driver
when
thecar
requires
service
.
See
620
Instruments
.
The
Multi-Information
Display
(MID)
unit
in
thecenter
of
the
dashboard
comes
in
a
variety
of
four
configurations,
the
most
advanced
being
the
On-Board
Computer
(OBC)
.
See
Fig
.
4
.
Al¡
versions
of
the
MID
have
a
clock
and
calendar
.
In
addi-
tion,
different
versions
areequipped
with
a
"check
control,"
display
for
fuel-economy
information
and
system
warnings
.
Consult
the
owner's
manual
for
fui¡
operating
instructions
.
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