1992 BMW M3 sensor

3
.
Break
open
plastic
retainer
in
back
of
instrument
clus-
ter
andremove
coding
plug
.
See
Fig
.
5
.

5
.
Reset
vehicle
mileage
.

1
ILO

NOTE-

Consultan
authorized
BMW
dealer
service
department
about
resetting
vehicle
mileage
using
the
special
BMW
Service
tester
.

Vehicle
speed
sender,
replacing

0

0013029

Fig
.
5
.



Remove
coding
plug
retainer
with
a
screwdriver
(arrow)
.

4
.
Install
coding
plug
and
new
retainer
.
Reinstall
instru-
ment
cluster
.

The
vehicle
speed
sender
supplies
an
electronic
pulsed

speed
signal
to
the
speedometer
.
The
sender
is
mounted
be-

neath
the
rear
of
the
car,
on
the
differential
cover
plate
.

1
.
Locate
vehicle
speed
sender
electrical
connector
at

back
of
differential
.
Depress
retaininglevers
on
con-
nector
and
remove
.
See
Fig
.
6
.

INSTRUMENTS
620-
3

0013180
Fig
.
6
.



Vehicle
speed
sender
harnessconnector
(A)
and
sender
(B)
.

2
.
Remove
vehicle
speed
sender
retaining
screws
and
re-

move
sender
from
differential
cover
.

3
.
On
installation,
replace
O-ring
and
coat
with
oil
(90W)
.
See
Fig
.
7
.

0011755
NOTE-



'

If
the
speedometer
is
malfunctioning,
check
the
vehicle



Fig
.
7,



O-ring
correctly
installed
on
vehicle
speed
sender,
speed
sensor
hamess
connectoron
the
rear
differen-
tial
.
Water
damage,
frayed
wires
and
corrosion
of
the
connectorcontactsareoftenthecause
ofspeedometer



4
.
Insta¡¡
sender
into
differential
and
tighten
mounting
malfunction
.



bolts
evenly
in
stages
until
the
sender
is
firmly
seated
.

Tightening
Torque

"
Vehicle
speed
sender

to
differential
cover
...
.
.....
6
.6-8
.4
Nm
(53-74
in-lb)

INSTRUMENT
CLUSTER

GENERAL

E36
cars
are
equipped
with
integrated
automatic
heating

and
air
conditioning
systems
.
Many
of
the
procedures
given
in

this
repair
group
require
that
the
A/C
refrigerant
charge
be

evacuated
using
specialized
equipment
.
See
A/C
System
Warningsand
Cautions
later
in
this
repair
group
.

HEATER
AND
CONTROLS

Blower
motor,
removing
and
installing

NOTE-

On
6-cylinder
cars,
the
plastic
top
enginecover
and
fuel
rail
covermustbe
removed
.
The
fuel
injectorhamess
re-
taining
screws
must
be
removed
and
the
harness
set
aside
.
The
engine
control
module
(ECM)
cover
must
be
removed,
the
control
unit
connectors
unplugged
and
the
harness
pulled
out
of
the
way
.
See
130
Fuel
Injection
.

1
.
Disconnect
negative
(-)
cable
from
battery
.

2
.
Open
hood
.
Unclip
engine
bulkhead
plenum
grille
at

base
of
windshíeld
and
remove
grille
.
See
Fig
.
1
.

HEATING
AND
AIR
CONDITIONING



640-1

640
Heating
and
Air
Conditioning

GENERAL
.
...
.
....
.
.
.
.
.
.
.
.
.
.......
.
.
.
640-1



Heater
andA/C
air
distribution
motor,

replacing(rotary-knob)
.
.
...
.
.
.
.......
.
640-10

HEATER
AND
CONTROLS
.
.....
.
.
.
.
.
.
.640-1



Rear
Window
Defogger
.
.
.



.
.
.
.
.
.
.
...
.
.
.
640-10
Blower
motor,
removing
and
installing
.
.
.
.
.
.
640-1



Rear
Window
Blower
(convertible
models)
.
.640-10

Blowermotor
resistor
pack,
replacing



.
.
.
.
.
.
640-3



AIR
CONDITIONING
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
640-11
Heater
valve,
replacing
...........
.
.
.
.
.
.
.
640-3

Heater
box,
removing
and
installing
.
.
.
.
.
.
.
.
640-4



A/CSystem
Warnings
and
Cautions
.
.
.
.
.
.
:640-11

Heater
core,
replacing
.....
.
.
:
....
.
.
.
.
.
.
.
640-6



A/C
compressor,
replacing
.
.
::.
:
:
.
.
.
.
.
.
.
.640-12

Heater
core
temperature
sensor,
replacing
.
.
640-7



A/C
Compressor
Clutch
.
.
.
.
.
.
.
:
.
.
.
.
.
.
.
.
.
640-13

Heater
andA/C
Control
Head
.
.
....
.
.....
.
640-7



A/C
condenser,
replacing
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
640-14

Heater
andA/C
control
head,
removing



A/C
receiver/drier,
replacing
.
.
.
.
.
.
.
.
.
.
.
.
.
640-15
and
installing
(rotary-knob)
.
.
....
.
......
640-7



A/C
expansion
valve,

Heater
andA/C
control
head,
removing



removing
and
installing
...
.
.....
.
.
.
.
.
.
.
640-16
and
installing
(digital-display)
.
.....
.
.....
640-8



A/C
evaporator,
removing
and
installing
.
.
..
640-17

Heater
andA/C
control
module,removing



A/C
evaporator
temperature
sensor,

and
installing
(rotary-knob)
.
.
...
.
.
.
.
.
.
.
.
640-8



replacing
.
.
.
.
.
.
..............
.
.
.
.
.
..
640-17

Heater
andA/C
control
module,removing



A/C
microfilter,
replacing
......
.
....
.
.
.
..
640-18

and
installing
(digital-display)
.
...
.
.
.
.
.
...
640-8

Sensor
fan
for
interior
temperature,



TABLES

replacing
.
.
.
....
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
640-9



a
.
Blower
Motor
Test
Values
.........
...
.
.
......
640-3

Heater
andA/C
AirDistribution
Motors
.
.
.
.
.
.
640-9



b
.
Heater
Core
Temperature
Sensor
Test
Values
...
.640-7

c
.
Evaporative
Temperature
Sensor
Test
Values
...
640-17

d
.
A/C
System
Fluid
Capacities
(total)
..
..........
640-18

0012527

Fig
.
1
.
Detach
grille
retaining
clips
(arrows)
and
pull
grille
upward
and
out
of
rubbergasket
.

CAUTION-

Prior
to
disconnectiog
the
battery,
read
the
battery
disconnection
cautionsgiven
at
the
front
of
this
manual
onpage
viii
.

HEATER
AND
CONTROLS

640-4



HEATING
AND
AIR
CONDITIONING

Heater
box,
removing
and
installing

The
heater
box,
located
underneath
thecenter
of
the
dash-

board,
houses
theheater
core,
the
A/C
evaporator,
and
asso-

ciated
sensors
and
actuators
.
Removal
of
theheater
box

requires
that
the
A/C
refrigerant
be
discharged
.

CAUTION-

"
Removing
the
heater
box
requires
evacuating
the
AIC
system
.
DO
NOT
attempt
this
procedure
without
proper
tools
and
training
.

"
Any
person
who
services
a
motor
vehicle
air
con-

ditioner
must,
by
law,
be
properly
trained
and
cer-
tified,
and
use
approved
refrigerant
recycling
equipment
.
Technicians
must
complete
an
EPA-
approved
recycling
course
to
be
certified
UU12639

Fig
.
10
.
Heater
core
mounting
nuts
at
left
sideof
bulkhead
(arrow)
.

1
.
Drain
engine
coolant
.
See
170
Radiator
and
Cooling



wiper
assembly
shown
removed
for
clarity
.

System
.

2
.
Remove
complete
dashboard
.
See513
Interior
Trim
.

3
.
Remove
blower
motoras
described
earlier
.

4
.
Remove
nut
retaining
water
hose
flange
to
rear
bulk-
head
.
I'ush
flange
to
one
side
.
See
Fig
.
9
.

Fig
.
9
.



Nut
retaining
coolant
hose
flangeat
bulkhead
(arrow)
.

NOTE-

Clear
any
remaining
coolant
from
the
heater
core
by
blowing
compressed
air
finto
the
coolant
feed
hose
.

HEATER
AND
CONTROLS

0012638b

6
.
Cut
wire
tie
holding
wire
harness
to
heater
box
and
dis-

connect
cable
harness
connector
from
heater
box
.
See

Fig
.
11
.

0012647

Fig
.
11
.
Harness
connectors
(A)
and
cable
tie
(B)
at
heaterbox,
under
driver
side
dash
.

7
.
Followingmanufacturer's
instructions,
connect
ap-

proved
refrigerant
recovery/recycling/recharging
unitto

A/C
system
and
discharge
system
.

8
.
Unbolt
A/C
refrigerantlines
flange
from
engine
bay
bulkhead
.
See
Fig
.
12
.

9
.
On
models
with
rotary-knob
A/C
control
head
:
Discon-
5
.
Remove
nuts
from
heater
box
retaining
bracket
on
en-



nect
wiring
harness
connectors
to
A/C
control
module
gine
bulkhead
left
side
.
See
Fig
.
10
.
Repeat
procedure



in
center
console
and
remove
module
.
See
Fig
.
13
.
for
right
side
nuts
.

640-6



HEATING
AND
AIRCONDITIONING

Heater
core,replacing

1.
Drain
engíne
coolant
.
See170
Radiator
and
Cooling

System
.

WARNING
-

Allow
the
cooling
system
to
cool
before
opening
or
drainíng
the
cooling
system
.

2
.
Remove
center
console
.
See
513
Interior
Trim
.

3
.
Remove
Multi-Information
Display
(MID)
module
.
See

620
Instruments
.

4
.
Remove
lower
dash
panel
and
knee
bolster
on
driver

side
.
See
513
Interior
Trim
.

Fig
.
17
.
Wire
harness
retaining
clips
and
wire
ties
at
heater
box
cover
5
.
Working
under
driver
side
of
dash,
remove
coolant



(arrows)
.
flange
from
heater
core
.
See
Fig
.
16
.

0012651

Fig
.
16
.
Bolts
at
3-way
coolant
flange
under
driver's
side
of
dash
(ar-
rows)
.

NOTE-

Residual
coolant
in
heater
core
will
spill
.
Protect
thecarpet
.

6
.
Working
at
front
of
driveshaft
tunnel,
unclip
wire
har-

nesses
and
move
to
one
side
in
front
of
heater
box
.
See
Fig
.
17
.

7
.
Remove
heatercore
temperature
sensorsas
described

later
in
this
repair
group
.

8
.
Remove
front
heater
box
cover
.
See
Fig
.
18
.

9
.
On
right
side
of
heater
box,
unclip
heater
air
duct
actu-
ating
lever
.
Remove
cross-rod
(with
flaps)
from
frontof
heater
core
.
See
Fig
.
19
.

HEATER
AND
CONTROLS

0012662

Fig
.
18
.
Screws
retaining
front
heater
box
cover
(shown
removed)
to
heater
box
(arrows)
.

0012661
Fig
.
19
.
Pry
heater
flap
actuating
lever
in
direction
A
.
Pull
offair
flap
cross-rod
in
direction
B
.

10
.
Pul¡
heater
core
up
and
backward,
away
from
heater
box
.
If
necessary,
remove
left
and
right
reinforcing
bracket
bolts
.
See
Fig
.
20
.

CAUTION-

Replace
coolant
flange
O-rings
and
tighten
fas-
teners
to
specified
torques
.

Tightening
Torques

1
.
Remove
center
console
.
See
513
Interior
trim
.

0012660

Fig
.
20
.
PA
heater
core
upand
towardback
of
car
.
Lower
mounting
bolts
for
steering
column
brace
and
glove
compartment
sup-
port
frame
may
have
to
be
removed
(arrows)
.

11
.
Installation
is
reverse
of
removal
.
Fill
and
bleed
cooling

system
.
See
170
Radiator
and
Cooling
System
.

"
Coolant
flange
to
heater
core
.
..
....
3
Nm
(27
in-lb)



Heater
andA/C
Control
Head

Heatercore
temperature
sensor,
replacing

The
automatic
heating
and
air
conditioning
systemuses

severa¡
sensors
to
control
interior
air
temperature
.
Use
the
fol-

lowing
procedure
and
the
data
in
Table
b
to
pinpoint
problems

with
theheater
core
sensors
.

2
.
Remove
Multi-Information
Display
(MID)
module
.
See

6201nstruments
.

HEATING
AND
AIR
CONDITIONING



640-7

0012648

Fig
.
21
.
Remove
heatercore
temperaturesensors
in
direction
shown
(arrow)
.

Table
b
.
Heater
CoreTemperatureSensor
Test

Values

Test
temperature



Resistance

4°F
(-20°C)



84
.39
-
109
.61
k
ohms

14
°
F
(-10°C)



48
.58
-
62
.09
k
ohms

32°F
(0°C)



28
.89
-
36
.40
k
ohms

68°F
(20°C)



11
.13
-
13
.83
k
ohms

140°F
(60°C)



2
.19
-
2
.78
k
ohms

212°F
(100°C)



0
.58
-
0
.77
k
ohms

Two
types
of
heater
and
aír
conditioning
control
heads
viere
installed
in
E36
cars
.
Early
models
have
control
heads
with
four
rotary
knobs
and
a
separate
control
module
.
A
flexible

shaft,
clipped
to
the
right
sideof
the
control
head,
controls
the
heater
flaps
.

Later
model
E36
cars,
starting
in
approximately
mid-1995,

have
digital
display
control
heads
with
buttons
.
The
A/C
con-
trol
module
is
integrated
with
the
digital
control
head
.

Heater
and
A/C
control
head,

removing
and
installing
(rotary-knob)

3
.
Pul¡
temperature
sensors
from
heater
box
and
discon-



1
.
Remove
Multi-Information
Display
(MID)
module
from

nect
harness
connectors
.
See
Fig
.
21
.



center
of
dash
.
See
620
Instruments
.

4
.
Installation
is
reverse
of
removal
.



2
.
Pul¡
off
outer
rotary
knobs
from
A/C
control
head
.
Re-

move
two
screwsonknob
bezels
.
Remove
control
pan-

el
face
plate
by
prying
it
off
control
head
gently
.
See
Fig
.

22
.

3
.
Carefully
push
control
head
back
into
dash
and
down-

ward
through
MID
opening
.
See
Fig
.
23
.

HEATER
AND
CONTROLS

Sensor

fan

Fig
.
25
.
Digital
display
A/C
control
head
components
.

2
.
Unscrew
left
and
right
screws
retaining
control
head
to
control
module
.
Press
retaining
clips
and
release
front
plate
from
control
head
.
Remove
A/C
control
module
from
control
head
housing
.

Sensor
fan
for
interior
temperature,

repiacing

A
small
electricfan,installed
in
the
A/C
control
head,
draws
cabin
air
past
the
climate
control
temperature
sensor
.

1.
Remove
A/C
control
head
as
described
earlier
.

2
.
Rotary-knob
control
head
:
Disconnect
electrical
con-
nector
from
top
of
control
head
housing
.
Pry
open
plas-

tic
housing
and
remove
sensor
fan
.
See
Fig
.
26
.

0013181

Fig
.
26
.
Sensor
fan
(A)
and
harness
(B)
in
back
of
A/C
control
head
(rotary-knob
control
head
shown)
.

3
.
Digital
display
models
:
Disconnect
electrical
harness

connector
from
control
head
housing
.
Remove
screws

holding
sensor
fan
to
bottom
of
control
moduleand
re-
move
.
Refer
to
Fig
.
25
.

4
.
Installation
is
reverse
of
removal
.

HEATING
AND
AIR
CONDITIONING



640-
9

Heater
and
A/C
Air
Distribution
Motors

The
recirculation,
fresh
air
and
othervent-duct
flaps
are
controlled
electrically
via
a
series
of
air
distribution
actuating
motors
.
Cars
with
the
rotary-knob
control
head
use
three
elec-
tromechanical
motors,
each
held
in
place
via
a
small
plastic
clip
.
See
Fig
.
27
.

Rightside
of
heater
box
l

Fig
.
27
.
Location
of
early
production
air
distribution
motors
(arrows)
.

Later
systems
(with
the
digital
display
control
head)
use
five
distribution
motors,
four
of
which
are
digítally
controlled
.
See
Fig
.
28
.

HEATER
AND
CONTROLS

Fig
.
42
.
Upper
A/C
condensermounting
bolts
(arrows)
.

8
.
Before
recharging,
evacuate
system
for
at
least
30
min
.
Recharge
system
following
equipment
manufacturer's
instructions
.
See
Table
d
.
A/C
System
Refrigerant

Capacities
.

A/C
receiver/drier,
replacing

The
A/C
receiver/drier
is
mounted
in
the
front
right
cornee
of
the
engine
compartment
behind
the
headlight
assembly
.

CAUTION-

The
receiver/drier
must
be
replaced
when
-There
is
dirt
in
the
AIC
system
-The
compressor
has
seized
or
has
been
re-
placed
for
any
reason
-The
condenser
or
evaporator
are
replaced
for
any
reason
-The
AIC
system
is
leaking
and
there
is
no
more
refrigerant
-The
AIC
system
was
open
for
24
hours
or
more
.

1
.
Following
manufacturer's
instructions,
connectan
ap-

proved
refrigerant
recovery/recycling/recharging
unit
to

A/C
system
and
discharge
system
.

2
.
Remove
right
headlight
assembly
.
See
630
Exterior
Lighting
.

CAUTION-
3
.
Disconnect
A/C
electrical
harness
connectors
.
See
Fig
.



Always
replaceO-rings
when
reconnecting
refrig-
43
.



erant
lines
.

4
.
Remove
refrigerant
pressure
lines
from
receiver/drier
.

Plug
lines
immediately
.

5
.
Remove
receiver/drier
mounting
bolts
.

0013182

6
.
Remove
underbody
splash
shield
on
passenger
side
.

See
Fig
.
44
.

7
.
Remove
passenger
side
brake
cooling
duct
.
Discon-

nect
outside
temperature
sensor
harness,
if
applicable
.

HEATING
AND
AIR
CONDITIONING



640-15

0012669

Fig
.
43
.
A/
C
receiver/drier
electrical
harness
connectors
(A),
pressure
line
retaining
bolts
(B),
andmounting
bolts
(C)
.

0012668
Fig
.
44
.
Passenger
sidesplash
shield
retaining
screws
(arrows)
.

8
.
Push
receiver/drier
down
andremove
from
underneath
car
.
Make
sure
that
receiver/drier
is
clear
of
any
electri-
cal
harnesses
.

9
.
Installation
is
reverse
of
removal
.

10
.
Before
recharging,
evacuate
system
for
at
least
30
min
.

Recharge
system
following
equipment
manufacturer's

instructions
.
See
Table
d
.
A/C
System
Refrigerant

Capacities
.

AIR
CONDITIONING

CAUTION
-

Always
replace
O-rings
when
reconnecting
refrig-
erant
fines
.

9
.
Before
recharging,
evacuate
system
for
at
least
30
min
.
Recharge
system
following
equipment
manufacturer's
instructions
.
See
Table
d
.
A/C
System
Refrigerant

Capacities
.

A/C
evaporator,
removing
and
installing

1
.
Followingmanufacturer's
instructions,
connectanap-proved
refrigerant
recovery/recycling/recharging
unit
to
A/C
system
and
discharge
system
.

2
.
Remove
complete
heater
boxas
described
earlier
.

3
.
Remove
expansion
valve
as
described
earlier
.

4
.
Unfasten
evaporator
sensor
electrical
harness
connec-
tor
and
puli
out
sensor
from
ieft
side
of
heater
box
.
See
Fig
.
50
.

Fig
.
49
.
Pull
out
evaporator
sensor
from
housing
in
direction
of
arrow
.

5
.
Remove
rear
heater
box
cover
.

6
.
Remove
clips
retaining
lower
evaporator
housingcover
.
Tilt
outheater
core,
then
pull
evaporator
out
of
housing
.

7
.
Installation
is
reverse
of
removal
.

CAUTION
-

Always
reptace
O-rings
when
reconnecting
refrtg-
erant
fines
.

8
.
Before
recharging,
evacuate
system
for
at
least
30
min
.

Recharge
system
following
equipment
manufacturer's
instructions
.
See
Table
d
.
A/C
System
Refrigerant

Capacities
.

HEATING
AND
AIR
CONDITIONING



640-17

8
.
Installation
is
reverse
of
removal
.



A/C
evaporator
temperature
sensor,

replacing

ou12b46

The
evaporator
temperature
sensor
is
mounted
in
the
left
(driver)
side
of
theheater
box
behind
thecenter
console
.

1
.
Remove
lower
dash
panel
and
knee
boister
on
driver
side
.
See
513
Interior
Trim
.

2
.
Remove
left
footwell
ventilation
duct
byremoving
re-
taining
rivet
in
bottom
of
duct
.
Pull
it
down
and
away
from
heater
box
.
See
Fig
.
50
.

Fig
.
50
.
Left
footwellventilatíon
duct
(arrow)
.

0o1300ba

3
.
Disconnect
sensor
electrical
connector
from
heater
box
.
Pull
sensor
straight
out
of
heater
box
.
Refer
to
Fig
.
49
.

4
.
Installation
is
reverse
of
removal
.
Table
c
.
lists
evapo-

rator
temperature
sensor
test
values
.

Tablec
.
Evaporator
Temperature
Sensor

Test
Values

Test
temp
.



Resistance

23°F
(-5°C)



11
.4
-11
.9
k
ohms

32°F
(0°C)



8
.8
-
9
.2
k
ohms

41
°F
(5°C)



6
.8
-
7
.2
k
ohms

50°F
(10°C)



5
.3-5
.6
k
ohms

59
°
F
(15°C)



4
.2
-4
.5
k
ohms

68°F
(20°C)



3
.3
-
3
.6
k
ohms

77°F
(25°C)



2
.6-2
.9
k
ohms

86°F
(30°C)



2
.1
-
2
.3
k
ohms

95°F
(35°C)



1
.7
-1
.9
k
ohms

AIR
CONDITIONING