1995 BMW M3 Heating and Air Conditioning

GENERAL
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400-1



INTERIOR
EQUIPMENT
......
.
.
.
.......
400-4
Seats
and
Seatbelts
.
.
.
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.
.....
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.
..
.
..
400-4
BODY
ASSEMBLY
.
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.....
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.400-2



Instruments
and
Controls
.
..
....
.
.
.
.
.
.
.
...
400-4

Exterior
and
Aerodynamics
....
.
.
.
.
.
.
.
.
.
.
.
400-2



Central
Body
Electronics
.......
.
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.
...
.
...
400-5

Coupe
Models
..
.
.
.
.
.
.......
.
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..
400-3



Electronic
Immobilization
System
.
.
.
...
.
...
400-5

Convertible
Models
.
.
.
.
.
.
.
.....
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.
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.
..
400-3



Heating
and
Air
Conditioning
.
...
.
.
.
.
.
.
.
...
400-6

GENERAL

This
section
covers
system
descriptions
and
general
ser-

vice
information
for
the
repair
groupsfound
in
4
Body
and
5

Body
Equipment
.

When
working
or
servicing
cars
equipped
with
SRS
air-

bag(s),
the
following
precautions
must
be
observed
to
prevent

injury
.

F19
.1
.
The
BMW
E36
coupe
.

400
Body-General

BODY-GENERAL
400-1

WARNING
-

"
Airbags
are
inflated
by
an
explosivedevice
.
Han-dled
improperly
or
without
adequate
safeguards,
airbag
units
can
be
very
dangerous
.
Special
pre-cautions
must
be
observed
prior
to
any
work
ator
near
the
driver's
side
airbag,
the
passenger's
side
airbag
(where
applicable),
or
the
side-impact
aírbags
(where
applicable)
.
See
721
Airbag
Sys-
tem
(SRS)
.

"
Always
disconnect
the
battery
and
cover
the
neg-
ative
(-)
battery
terminalwith
an
insulator
before
starting
diagnostic,
troubleshooting
or
service
work
oncars
fitted
with
SRS,
and
before
doíng
any
welding
on
the
car
.

0013098

GENERAL

400-
6
BODY-GENERAL

Heating
and
Air
Conditioning

The
electronically
controlled
heating
and
air
conditioning

systemusesan
extra
large,
infinitely
variable
radial
blower
motor
for
good
distribution
of
air
.
Fresh
air
enters
through
the
grille
below
the
engine
hood
and
finto
the
passenger
compart-
ment
via
the
dashboard
and
footwell
vents
.
See
Fig
.
5
.

Repair
information
for
the
heating
and
air
conditioning
sys-

tem
is
covered
in
640
Heating
and
Air
Conditioning
.

Fig
.
5
.



Heating
and
air
conditioning
ventilation
plan
.

INTERIOR
EQUIPMENT

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

640-2



HEATING
AND
AIR
CONDITIONING

3
.
Remove
wiring
harness
retaining
clip
at
bulkhead
.
Re-

move
screws
retaining
wiring
harness
cover
and
pull

cover
forward
.
See
Fig
.
2
.

0012529

Fig
.
2
.
Ming
harness
cover
screws
at
base
ofwindshield
(arrows)
.

4
.
On
passenger
side,
push
aside
wiring
harness
and
re-

move
two
screws
retaining
plenum
housing
.
See
Fig
.
3
.

Fig
.
3
.



Ríghtside
plenum
retaining
screws
(arrows)
.

VU1L535

5
.
On
driverside,
push
aside
wiring
harness
and
remove

screw
retaining
plenum
.
Pull
plenum
up
and
remove
from
engine
bay
.
See
Fig
.
4
.

6
.
Unclip
blower
motor
housing
cover,
disconnect
control

cable,
and
turn
center
retainer
1
/4
turn
to
remove
cover
.
See
Fig
.
5
.

7
.
Disconnect
electrical
connectors
from
blower
motor
.

8
.
Remove
left
upper
section
of
blower
housingby
detach-
ing
spring
clipsat
edge
of
housing
.
See
Fig
.
6
.

HEATER
AND
CONTROLS

Fig
.
4
.



Remove
screw
at
A
and
pull
air
plenumupward
.

0012534

0012636

Fig
.
5
.



Blower
motor
housing
clips
(A)
;
control
cable
(B)
;
and
center
retainer(C)
.

i
[u6,

Fig
.
6
.



Spring
clips
(arrows)
on
driver
sideof
blower
housing
.

9
.
Release
blower
motor
retaining
strap
andremove
blow-
er
motor
and
fans
fromcowl
opening
.

NOTE-

Twist
and
rotate
blowermotor
assembly
to
facilítate
re-
moval
from
opening
.
If
the
blower
motor
is
to
be
rein-stafled,
use
care
not
to
damage
fan
wheels
during
removal
.
ff
the
blower
motor
fs
to
be
replaced,
cut
offfan
wheels
at
center
to
aid
in
removal
.

10
.
Installation
is
reverse
of
removal
.
When
installing
a
re-
placement
blower
motor,
instan
motor
into
cowlarea
before
installing
fan
wheels
.
Blower
motor
test
specifi-

cations
are
listed
in
Table
a
.

NOTE
-

On
replacementblowermotors
from
BMW,
thefan
wheels
come
unattached
to
aid
in
installation
.
Locatearrow
on
blower
motor
and
instan
fan
wheels
atthis
po-
sition
.
Be
sure
color
coolng
matches
.
Retain
fan
wheels
using
the
new
clips
.
See
an
authorized
BMW
parts
de-
partment
for
the
latest
parts
information
.

Table
a
.
Blower
Motor
Test
Values

Testingvoltage



13
VDC

Operating
voltage



9-15
VDC

Max
.
current
consumption
(approx
.)



12
amps

Maximum
speed



3,600-4,000rpm

Axialplay
(max
.
allowable)



1
.0
mm
(0
.04
in
.)

Blower
motor
resistor
pack,
replacing

The
blower
resistor
pack
is
clipped
into
the
upper
left
side
of
theheater
box
.

1
.
Remove
lower
left
dash
trim
panel
.
See513
Interior

Trim
.

2
.
Working
under
left
(driver's)
side
of
dash,
unclip
and

pulí
out
resistor
pack
from
sideof
heater
box
.
Remove

harness
connector
from
resistor
pack
.
See
Fig
.
7
.

3
.
Installation
is
reverse
of
removal
.

Heater
valve,
replacing

The
two-way
heater
valve
is
located
in
the
rear
of
the
engine

compartment
on
the
driver
side
.
The
solenoid
operated
valves

control
the
coolant
flow
through
the
dual-chamber
heater

core
.

1
.
Drain
engine
coolant
.
See
170
Radiator
and
Cooling

System
.

HEATING
AND
AIR
CONDITIONING



640-
3

uuiGO4I

Fig
.
7
.



Blower
fan
resistor
pack
(black
arrow)
and
resistor
pack
re-
ceptacle
(white
arrow)
below
left
sideof
dash
.

WARNING
-

Allow
the
cooling
system
to
cool
before
opening
ordraining
the
cooling
system
.

2
.
Disconnect
hoses
and
harness
connector
at
heater
valve
.
See
Fig
.
8
.

001[ó38b

Fig
.
S
.



Hoses
(A)
and
harnessconnector
(B)
at
heatervalve
.

3
.
Carefully
pull
heater
valve
out
of
rubber
mounting
and

pull
up
and
out
of
engine
compartment
.

4
.
Installation
is
reverse
of
removal
.
Use
new
hose

clamps
.
Inspect
hoses
and
replace
asnecessary
.

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
.

Fig
.
12
.
Mounting
bolt
for
A/C
refrigerant
line
flange
(arrow)
.

001Suu7

Fig
.
13
.
A/
C
control
module
(A)
behind
center
console
.
Arrows
pointto
electrical
harness
connectors
to
be
disconnected
.

CAUTION
-

Replace
heater
and
AIC
flange
O-rings
and
tight-

en
fasteners
to
specified
torques
.

0012644

HEATING
AND
AIR
CONDITIONING



640-5

Fig
.
14
.
Heating
and
ventilation
ducts
on
left
side
of
heater
box
(arrows)
.
Right
side
ducts
are
similar
.

Fig
.
15
.
Heater
box
retaining
bracket
in
center
console
(arrow)
.

0012645

10
.
Unclip
andremove
heating
and
ventilation
ducts
on



Tightening
Torques

sides
of
heater
box
.
See
Fig
.
14
.



"
A/C
refrigerant
lines
flange

to
bulkhead
..............
.
..
..
.
3
.5
Nm
(31
in-lb)

11
.
Remove
heater
box
retaining
bracket
on
center
tunnel



"
Water
hose
flange
to
bulkhead

and
remove
heater
box
.
See
Fig
.
15
.



(M6
nut)
................
.
...
..
3
.5
Nm
(31
in-lb)

"
Heater
box
retaining
bracket

12
.
Installation
is
reverse
of
removal
.
Evacuate
and
re-



to
tunnel
................
.
..
..
.
4
.5
Nm
(40
in-lb)

charge
A/C
system
using
specialized
equipment
.
Fill

and
bleed
cooling
system
.
See
170
Radiator
and

Cooling
System
.

HEATER
AND
CONTROLS

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
.