fuel type BMW 318i 1996 E36 User Guide

130-
8



FUEL
INJECTION

Fig
.
8
.



Fuel
pump
relayterminal
identification
.
1.
Peel
back
rubber
boot
on
oxygen
sensor
electrical
har-
ness
connector
(car
wiring
side)
.
With
connector
at-
Oxygen
sensor,
testing



tached
to
sensor,
connect
digital
voltmeter
to
pins
1
(BOSch
systems
only)



and
2
in
rear
of
connector
.
See
Fig
.
10
.

CAUTION-

"
The
information
inthis
sectionapplies
to
Bosch
engine
management
systems
only
.

"
The
Siemens
MS
41
.1
system
uses
resistive-type
oxygen
sensors
.
This
sensor
uses
a
5-volt
refer-
ence
signal
input
and
the
output
to
the
ECM
var-
ees
from
1-5
volts,
in
stepped
increments
based
on
oxygen
content
in
the
exhaust
.

NOTE-

"
On
pre-08D
11(1992-1995)
cars,
there
is
one
oxygen
sensor
mounted
upstream
of
the
catalytic
convert-
er(s)
in
the
exhaust
pipe
.
See
Fig
.
9
.
"
On
OBD
11
cars
(1996-1998)
cars,
there
is
one
oxygen
sensor
before
andone
after
each
catalytic
converter
.

"
OnM52
and
S52US
engines,
the
front
pairof
oxygen
sensors
are
installed
in
the
exhaust
manifolds
.

The
oxygen
sensor
providesan
input
voltage
signal
(0-1
VDC)
to
the
ECM
based
on
the
oxygen
content
in
the
exhaust
gas
.
TO
generate
voltage,
the
sensor
temperature
must
exceed
575°F
(300°C)
.
Therefore
it
ís
electrically
heated
.

NOTE-

"
The
test
given
below
is
not
a
conclusive
test
of
oxygen
sensor
efficiency
and
does
not
test
how
quickly
the
oxygensensor
can
react
to
changing
conditions
.

"
Pin
numbers
and
wirecolors
can
vary
.
Always
check
the
wiring
diagrams
to
conflrm
wire
color
and
pinas-
signment
.

ELECTRICAL
CHECKS
AND
COMPONENT
TESTING

0013135

Fig
.
9
.



Oxygen
sensor
location
(arrow)
ahead
of
catalytic
converter
.
3181
model
with
M42
engine
shown
.

1
.
Black
(ground)
2
.
Grey
(signal)



4
.
White
(heater
circuit)
3
.
White
(heater
circuit)

0013189
Fig
.
10
.
Oxygen
sensor
connector
terminal
identification
(sensor
sede)
.
Terminals
numbers
are
molded
into
connector
.

2
.
Start
engine
.
Oxygen
sensorshould
start
to
output
a
fluctuating
voltage
within
a
short
period
.
If
voltage
is
in-
correct,
turn
engine
off
and
check
preheater
circuit
as
described
below
.

WARNING
-

Exhaust
manifolds
and
pipes
can
be
hot
enough
to
cause
serious
burns
.
Wear
suitable
heavy
gloves
and
other
appropriate
protection
.

130-
1
4



FUEL
INJECTION

NOTE-

Be
sure
to
retrieve
thrust
washer
behind
fuel
pressure
regulator
on
6-cylinder
engine
.

4
.
Installation
is
reverse
of
removal
.
Replace
O-rings
.

Fuel
pressure
regulator,
replacing

(under
car
mount)

WARNING
-

Fuel
will
be
discharged
.
Do
not
disconnect
any
wires
that
could
cause
electrical
sparks
.
Do
not
smoke
or
work
near
heaters
or
other
fire
hazards
.
Keep
an
approved
tire
extinguisher
handy
.

On
late
4-
and
6-cylinder
cars,
the
fuel
pressure
regulator
is

mounted
beneath
the
left
sideof
the
car,
under
a
protective

cover
.
See
Fig
.
20
.

0012726

Fig
.
20
.
Fuel
pressure
regulatorlocation
underneath
car
(arrow)
.
Vac-
uum
hose
to
regulator
is
shown
at
A
.
(Protective
cover
has
been
removed
.)

5
.
Installation
is
reverse
of
removal
.
Replace
O-rings
.

BOSCH
DME
Ml
.
7
COMPONENT
TESTS
AND
REPAIRS

BOSCH
DME
Ml
.7
COMPONENT

TESTS
AND
REPAIRS

CA
UTION-

Use
only
a
digital
multimeter
when
testing
compo-
nents
and
wiring
.
Use
of
an
analog
VOM
may
damage
the
engine
control
module
.

4-cylinder
cars
with
M42
engines(1992
to
1995)use
the

Bosch
DME
M1
.7
fuel
injection
system
.

Electrical
tests
of
the
main
and
fuel
pump
relays
and
the

DME
engine
control
module
(ECM)
are
covered
earlier
in
this

section
.
Fuel
pump
tests
arecovered
in
160
Fuel
Tank
and

Fuel
Pump
.

Air
flow
sensor,
testing
and
replacing

DME
M1
.7
fuel
injection
uses
a
volume
air
flow
type
sensor

with
integrated
intake
air
temperature
(IAT)
sensor
.
The
sen-

sor
provides
a
varyingvoltage
signal
to
the
ECM
based
on
the

position
of
the
air
vane
.
As
the
vane
doorswings
open
thepo-
tentiometer
increases
the
voltage
signal
to
the
ECM
.
The
IATsensor
adapts
theoutput
signal
to
the
ECM
based
on
intake

air
temperature
.

1
.
Check
ECM
reference
voltage
to
sensor
:

"
Peel
back
rubber
boot
from
air
flow
sensor
harness

connector
.

"
Turn
ignition
keyon
.
"
Check
for
5
volts
between
terminal
1
of
harness
con-
nector
and
ground
.
See
Fig
.
21
.

"
Turn
ignition
key
off
.

"
If
voltage
is
not
present
or
incorrect,
check
wring
from

ECM
and
check
air
flow
sensor
reference
voltage
out-

put
at
ECM
.
See
Table
h
.
1
.
Working
under
car
below
driver's
seat,
remove
protec-
tive
cover
from
below
fuel
pressure
regulator
.

"
Remove
intake
air
bootfrom
sensor
.
2
.
Remove
vacuum
hosefrom
fuel
pressure
regulator
.



"
Connect
a
digital
multimeter
(ohms)
across
terminais
1

and
2
.
Swing
air
flow
sensor
vane
through
its
travel
3
.
Remove
locking
clip
retaining
fuel
pressure
regulator
.



range
.
Resistance
should
change
steadily
without
in-

terruption
.
4
.
Wrap
a
shop
rag
around
regulator,
then
remove
regula-



"
If
any
faults
are
found,
the
air
flow
sensor
is
faulty
and
tor
from
213
way
valve
by
pullingstraight
out
.



should
be
replaced
.

2
.
Check
air
flow
sensor
potentiometer
:

3
.
Check
IAT
sensor
resistance
:

"
With
harness
connector
disconnected
at
air
flow
sen-
sor,
check
resistance
across
sensor
terminais
4
and
5

of
air
flow
sensor
.
Compare
tests
results
to
values
in
Table
d
given
later
.
If
any
faults
are
found,
the
air
flow
sensor
should
be
replaced
.

130-
1
6



FUEL
INJECTION

Throttie
position
sensor
(TPS),



Idie
speed
control
valve,
testing
and
replacing



testing
and
replacing

The
throttie
position
sensor
(TPS)
is
mounted
on
the
side
of



¡die
speed
is
maintained
by
the
ECM
via
the
¡die
speed
con-

the
throttie
housing
and
is
directly
connected
to
the
throttie



trol
valve
.
See
Fig
.
24
.
¡die
speed
is
adaptive
through
the
valve
shaft
.
The
ECM
sends
a
voltage
signal
to
the
potentiom-



ECM
and
no
¡die
speed
adjustments
can
be
made
.
Before
eter-type
sensor
and
monitors
the
voltage
that
comes
back
.



testing
the
valve,
confirm
that
the
throttie
position
sensor(TPS)
is
working
correctly
.

Check
TPS
function
by
disconnecting
the
harnessconnec-

tor
and
checking
reference
voltage
and
sensor
resistance
.

See
Table
e
and
Fig
.
23
.
If
voltage
is
not
present,
check
the

output
voltage
signal
from
the
ECM
and
check
the
wiring
be-
tween
the
sensor
and
the
ECM
.
If
the
sensor
resistance
is
in-
correct,
replace
the
throttie
position
sensor
.

NOTE
-

The
throttie
position
sensor
is
not
adjustable
.
If
test
re-
sults
are
íncorrect,
the
sensor
should
be
replaced
.

Table
e
.
Throttle
Position
Sensor
Tests

(DME
1
.7)

Testconditions



1
Terminais



1
Test
value

Harness
connec-



(
1
and
ground
in



15
VDC
(approx
.)
tor
disconnected,



harness
connector
ignition
on

0013235

Fig
.
23
.
Throttieposition
sensor
terminal
identification
on
M42
engine
.

Harnessconnec-



I
1
and
3
at
sensor



(
4k
ohms
(approx
.)
tor
disconnected,



terminais
ignition
off
Connector
dis-



1
and
2
at
sensor



Continuously
vari-
connected,
igni-



terminais



able
from
1-4
k
tion
off
.
Throttle



ohms
(approx
.)
with
rotated
from
¡die



out
interruption
to
fui]
position

BOSCH
DME
Ml
.
7
COMPONENT
TESTS
AND
REPAIRS

Fig
.
24
.
¡die
speed
control
valve
(arrow)
on
M42
engine
.

NOTE
-

"
The
tests
given
below
are
electrical
checks
only
.
They
do
not
check
the
mechanical
operation
of
the
valve
or
if
the
valve
is
sticking
or
worn
.
If
the
valve
is
suspect,
substituting
a
known
good
valve
is
the
best
way
to
check
for
amechanical
fault
.

1
.
Check
battery
(+)
voltage
to
valve
:

0013226

"
Disconnect
harness
connector
from
valve
.
"
Check
for
battery
voltage
at
terminal
2
(red/white
wire)
.
"
If
voltage
is
not
present
check
wiring
between
valve
and
main
relay
(terminal
87)
.

2
.
Check
that
ECM
signal
is
reaching
valve
:

"
With
engine
running,
check
that
¡die
speed
control
valve
is
audibly
buzzing
.
"
If
valve
is
not
working,
disconnect
wiring
harness
con-
nector
.

"
Connect
12V
probe
light
across
connector
terminais
.
"
Turn
ignition
key
on
;
probe
should
light
.
lf
probe
does
nof
light,
check
the
wiring
from
the
ECM
(pin
29)
to
the
valve
.
See
Table
h
.
lf
probe
does
light
but
¡die
quality
is
poor,
the
valve
is
most
likely
sticking
and
or
worn
and
should
be
replaced
.

BOSCH
DME
MM
AND
M33
.1

COMPONENT
TESTS
AND
REPAIRS

Consult
Table
a
for
engine
application
information
for
the

Bosch
DME
3
.1
and
3
.3.1
systems
.

The
DME
3
.1
and
DME
3
.3
.1
systems
are
similar
in
opera-

tion,
with
knock
control
and
VANOS
operation
being
the
key

differences
.
DME
3
.1
engines
arenot
equipped
with
VANOS

or
knock
detectors,
while
the
DM
E3
.3
.1
system
is
.

CA
UTION-

Use
onty
a
digital
multimeter
when
testing
wiring
.
Use
of
an
analog
VOM
may
damage
the
engine
control
module
.

Fig
.
25
.
Mass
air
flow
sensor
.
Hot
wire
sensor
usedon
carswith
DME
Electrical
tests
of
the
main
and
fuel
pump
relays
and
the



3
.1
(1992
6-cylinder
models)
.

DME
engine
control
module
(ECM)
are
covered
earlier
in
this

section
.
Fuel
pump
tests
are
covered
in
160
Fuel
Tank
and



CAUTION-
Fuel
Pump
.
Use
only
a
digital
multimeter
when
checking
the
mass
air
flow
sensor
.
An
analog
meter
can
dam-
Mass
Air
Flow
Sensor



age
theair
flow
sensor
.

There
are
two
types
of
mass
air
flow
sensors
used
onthe



1
.
Disconnect
air
flow
sensor
from
air
cleaner
only
.
Leave

cars
covered
by
this
section
.
Testing
procedures
vary
de-



it
connected
to
duct
leading
to
intake
manifold
and

pending
on
type
installed
.
The
airflow
sensor
is
not
adjustable



leave
wiring
harness
connected
.

and
must
only
be
tested
with
a
digital
multimeter
.

Mass
Air
FlowSensor
Variants

"
1992
M50
engine

DME
M3
.1
.
.
.
.
...
..
mass
air
flow
sensor-hot
wire

"
1993-1995
M50
and
S50US

DMEM33
.1)
.
...
...
.
mass
air
flow
sensor-hot
film

Mass
air
flow
sensor
(hot
wire),

testing
and
replacing

When
the
engine
is
running,
a
current
is
used
to
heat
a
thin

wire
in
the
center
of
the
sensor
.
See
Fig
.
25
.
The
current
in
the

wire
is
regulated
to
maintain
a
temperature
of
100°C
more

than
the
air
passing
over
it
.
The
current
used
to
heat
the
wire

is
electronically
conneced
into
a
voltage
measurement
corre-

sponding
to
the
mass
of
intake
a¡
r
.

To
keep
the
wire
clean,
it
is
heated
to
a
temperature
of
about

1,000°C
(1,830°F)
for
one
second
.
This
"burn-off"
cycle
takes

place
automatically,
four
seconds
after
the
engine
is
tumed
off
.

lf
thehot
wire
breaks
or
if
there
is
no
output
from
the
air
flow

sensor,
the
ECM
automatically
switches
to
a
"limp-home"

mode
and
tucos
on
the
Check
Engine
light
.
The
engine
can

usually
be
started
and
driven
.
The
air
flow
sensor
has
no
inter-

nal
moving
parts
and
cannot
be
serviced
.

FUEL
INJECTION



130-
1
7

2
.
Start
engine
and
run
it
to
normal
operating
temperature
.

3
.
Rev
engine
toat
least
2,500
rpm,then
shut
it
off
.
Look

through
meter
at
hot
wire
.
After
approximately
four
sec-

onds
wire
should
glow
brightly
for
about
one
second
.

NOTE
-

If
the
wire
glowsas
specified,
then
the
airflow
meter
and
ECM
are
probably
operating
correctly
.
lf
the
wire
does
not
glow,
continue
testing
.

4
.
lf
the
wire
does
not
glow,
remove
air
flow
sensor
and

look
through
it
to
see
if
wire
is
broken
.
lf
wire
is
broken,

meter
will
have
to
be
replaced
.

5
.
Reinstall
air
flow
sensor
and
harness
connector
.
Peel

back
rubber
bootfrom
harness
connector
.
Working

from
rear
of
connector,
connect
digital
voltmeter
across

terminals
1
and
4
.
See
Fig
.
26
.

6
.
Start
and
rev
engine
toat
least
2,500
rpm,thenshut
it

off
.
After
about
4
seconds,
voltage
should
riseto
about

4
volts
for
about
one
second
.
lf
voltage
is
present,
but

wire
does
not
glow,
air
flow
sensor
is
faulty
and
should

be
replaced
.

7
.
lf
voltage
is
not
present
in
step
6,
turn
ignition
key
on

and
check
for
voltage
and
ground
at
sensor
.
There

should
beground
at
pin
4
.
There
should
be
positive
(+)

battery
voltage
at
pin
2
.

BOSCH
DME
M3
.1
AND
M32
.1
COMPONENT
TESTS
AND
REPAIRS

Table
f
.
Engine
Coolant
TemperatureSensor
or

Intake
Air
TemperatureSensor
Test
Values

(DME
3
.113
.3
.1)

Test
temperatures



Resistance
(k
ohms)

14±
2°F
(-10
±
1'C)



7-11
.6

68±
2°F
(20
±
1'C)



2
.1
-2
.9

17612°F
(80
t
V
C)



0
.27-0
.40

NOTE

The
test
values
listed
represent
only
three
test
points
from
a
continuous
resistance
NTC
sensor
.
Check
the
full
linear
response
to
increasing
temperatures
as
the
engine
warms
up
.

3
.
If
ECT
sensor
fails
these
tests,
it
is
faulty
and
should
be

replaced
.
If
no
faults
are
found,
reconnect
electrical

harness
.

WARNING
-

Do
not
replace
the
ECT
sensor
unless
the
engine
is

cold
.
Hot
coolant
can
scald
.

NOTE-

Use
"



a
new
copper
sealing
washer
when
installing
sensor
.
Replace
any
lost
coolant
.

Tightening
Torque

"
Engine
coolant
temperature
sensor

to
cylinder
head
.........
..
.
..
...
13
Nm
(10
ft-lb)

Intake
air
temperature
(IAT)
sensor,

testing
and
replacing

The
intake
air
temperature
(IAT)
sensor
signal
is
usedasa

correction
factor
for
fuel
injection
and
ignition
timing
.
Thissen-

sor
is
mounted
in
the
intake
manifold
behind
the
throttle
posi-

tion
switch
.
See
Fig
.
28
.

Check
TPS
function
by
disconnecting
theharnessconnec-
1
.
Check
that
ECM
reference
voltage
is
reaching
IAT
sen-



tor
and
testing
continuity
across
the
terminalswhile
changing
sor
:



the
throttle
position
.
Resistance
test
values
are
listed
below
.
If

"
Disconnect
IAT
sensor
harness
connector
.



the
resuits
are
incorrect,
replace
the
throttle
position
sensor
.

"
Turn
ignition
keyon
.



See
Fig
.
29
.

"
Check
for
5
volts
between
supply
voltage
wire
of
har-

ness
connector
and
ground
.
NOTE-
"
Turn
ignition
key
off
.
The
throttle
position
sensor
is
not
adjustable
.
If
test
re-
sults
are
incorrect,
the
sensor
should
be
replaced
.

IAT
Sensor
Supply
Voltage

"
M50/S50US
engines
.
........
grey
wire
and
ground

FUEL
INJECTION



130-19

Fig
.
28
.
Intake
air
temperature
sensor
location
on
M50/S50US
engine
(arrow)
.

If
voltage
is
not
present
or
incorrect,
check
wiring
from
ECM

and
check
reference
voltage
signal
at
ECM
(pin
77)
.
See
Ta-

ble
i
or
Table
j
.

2
.
Check
IAT
sensor
resistance
:

"
With
harness
connector
disconnected,
check
resis-

tance
acrosssensor
terminals
.
Compare
tests
resuits
to
values
in
Table
f
given
earlier
.

"
If
IAT
sensor
fafs
thistest
it
is
faulty
and
should
be
re-

placed
.

3
.
If
no
faults
are
found,
reconnect
electrical
harness
.

Throttle
position
sensor
(TPS),

testing
and
replacing

The
throttle
position
sensor
(TPS)
is
mounted
on
the
side
of

the
throttle
housing
and
is
directly
connected
to
the
throttle

valve
shaft
.
The
ECM
sends
a
voltage
signal
to
the
potentiom-

eter-type
sensor
and
monitors
the
voltage
that
comes
back
.

BOSCH
DME
M3
.
1
AND
M32
.1
COMPONENT
TESTS
AND
REPAIRS

0013ZIM
Fig
.
42
.
Engine
control
module
(ECM)
located
in
compartment
in
right-rearof
engine
compartment
(arrow)
.

NOTE-

Replacement
ECMs
must
be
coded
with
application
in-
formation
(Le
.
engine
code,
transmission
type,
etc
.)
pri-
or
to
installation
.
Consult
an
authorized
BMW
dealer
before
replacing
the
ECM
.

ECM
pin
assignments
are
given
in
Tables
h
through
Table
I.
This
information
can
be
helpful
when
diagnosing
faultsto
or
from
the
ECM
.
If
al¡
inputs
and
wiring
are
OK
butoperational
problems
still
exist,
the
ECM
itself
may
be
faulty
.

Fig
.
43
.
ECM
pin
numbers
as
seen
from
back
of
ECM
connector
.

FUEL
INJECTION



130-
2
7

Generally,
absence
of
voltage
or
continuity
means
there
is
a
wiring
or
connector
problem
.
Test
results
with
incorrect
values
do
notnecessarily
mean
that
a
component
is
faulty
:
Check
for
loose,
broken
or
corroded
connections
and
wiring
before
re-
placing
components
.
If
the
results
are
still
incorrect,
test
the
component
itself
.
For
engine
management
system
electrical
schematics,
see
Electrical
Wiring
Diagrams
.

CAUTION-

Always
waitat
least
40
seconds
after
tuniing
off
the
ignition
before
removing
the
connector
from
the
engine
control
module
(ECM)
.
If
the
connec-
tor
is
removed
before
this
time,
residual
power
in
the
system
relay
may
damage
the
ECM
.

"
Always
connector
disconnect
the
control
module
connector
and
meter
probes
with
the
ignitionoff
.

When
making
checks
at
the
ECM
itself,
a
breakout
box
should
be
used
to
allow
tests
to
be
made
with
the
connector
attached
to
the
ECM
.
This
also
prevents
damage
tothe
small
termínals
in
the
connector
.
As
an
alternative,
theharness
con-
nector
housing
can
be
separated
so
that
electrical
checks
can
be
made
from
the
back
of
the
connector
.
ECM
pin
numbering
is
shown
in
Fig
.
43
.

NOTE
-

On
cars
with
tractioncontrol,
do
not
confuse
the
throttle
position
sensor
on
the
main
throttle
body
with
the
throt-
tle
position
switch
on
the
secondary
throttle
body
.

27
Lb
2L4
LJ
22
©©®®17
©©®©©~©©®©~~rui~~ru

®®®®®®®®®®®®®®®IZA®®®®®®®®®®®®®®®®®

1
>I-
0013211

ECM
PIN
ASSIGNMENTS

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