1997 BMW 328i heater core

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

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

WARNING

Your
common
sense,
good
judge-
ment,
and
general
alertness
are
cru-
cial
tosafe
and
successful
service
work
.
Before
attempting
any
work
on
your
BMW,
read
the
warnings
and
cautions
on
page
vi¡
and
the
copyright

page
at
the
frontof
the
manual
.
Review
these
warnings
and
cautions
each
time
you
prepare
to
work
on
your
BMW
.
Please
also
read
any
warnings
and
cautions
that
accom-
pany
the
procedures
in
the
manual
.

Fuel
pressure
regulator
See
Fuel
injection
Fue]
pump
general
information
160-1
electrical
tests
160-7
power
consumption,
testing
160-7
delivery
tests160-8
delivery
volume,
testing
g
160-9
electrical
circuit,
checking
160-7
fuse
and
relay
160-6
level
sender
See
pump/fuel
leve¡
sender
operating
fuel
pump
for
tests
160-6
pump/fuel
level
sender
(left
side),
removing/installing
160-6
pump/fuel
leve¡
sender
(right
side),
removing/installing
160-5
relieving
fuel
pressure
and
connecting
fue¡
pressure
gauge
160-8
Fueltank
and
lines
general
information
160-1
draining
160-2
evaporative
control
system
160-4
leve¡
senders,
testing
160-5
removing/installing
160-3
Fundamentals
for
the
do-it-yourself
owner
general
information
010-1
advice
for
the
beginner
010-4
cleanliness
010-4
electrical
testing
010-6
gaskets
and
seals
010-5
non-reusable
fasteners
010-5
planning
ahead
010-4
tightening
fasteners
010-5
wire
repairs
010-6
buying
parts
010-6
genuine
BMW
parts
010-6
information
you
need
to
know
010-7
non-returnable
parts
010-7
emergencies
010-11brake
fluid
leve¡
010-13
car
will
not
start
010-11
changinga
tire
010-11
check
enginewarning
light
010-13
dim
Iights
010-13
jump
starting
car
010-12
low
o]I
pressure
010-13
overheating
010-12

Emergencies
(cont
.)
spare
parts
kit
010-14
towing
010-13
gettingstarted
010-2
lifting
thecar
010-3
raising
car
safely
010-3
safety
010-2
working
under
car
safely
010-4
how
to
use
this
manual
010-2
warnings,
cautions
and
notes
010-2
service
010-7
tools
010-7
basic
tool
requirements010-8
BMW
specialtools
010-11
feeler
gauges
010-10
jack
stands
010-9
oil
change
equipment
010-9
torque
wrench
010-10
volt-ohm
meter
(VOM)
or
Multi-
meter010-10
Fuses
See
Electrical
component
locations

G

Gaskets
See
Fundamentals
for
the
do-it-
yourself
owner
Gearshift
See
Gearshift
linkage
Gearshift
linkagegeneral
information
250-1
automatic
shiftlock,
checking
function
250-5
automatic
transmission
gearshift
250-
3
gear
position/neutral
safety
switch,
replacing
(automatic
transmission)
250-4
gearshift
lever,
installing
(manual
transmission)
250-2
gearshift
lever,
removing
(manual
transmission)
250-1
gearshift
mechanism,
adjusting
(automatictransmission)
250-3
manual
transmission
gearshift
250-1
shift
interlock,
checking
function
(automatic
transmission)
250-6Glass
See
Door
windows
Glove
compartment
See
Interior
trim
Grille
See
Exterior
trim,
bumpers
Guibo
(flex
disc)
See
Driveshaft

Handle,
door
See
Doors
Hardtop
See
Body-general
Headlight
See
Exterior
lighting
Headlight
switch
See
Switches
and
electrical
accessoriesHeater
box
See
Heating
Heater
core

See
Heating
Heater
valve
See
Heating
Heating
general
information
640-1
air
distribution
motors
640-9
air
distribution
motor,
replacing
(rotary
knob)
640-10
blower
motor,
removing/installing
640-1blower
motor
resistor
pack,
replacing
640-3
control
head
640-7
removing/installing
(digital-display)
640-8
removing/installing
(rotary
knob)
640-7
control
module
removing/installing
(digital-display)
640-8
removing/installing
(rotary
knob)
640-8
heater
box,
removing640-4
heater
core,
replacing
640-6
heater
core
temperature
sensor,
replacing
640-7
heater
valve,
replacing
640-3
rear
window
blower
(convertible
models)
640-10
reas
window
defogger
640-10sensor
fan
forinterior
temperature,
replacing
640-9warnings
and
cautions
640-11
Hood
See
Fenders,
engine
hood

Idle
speed
See
Maintenance
program
Idle
speed
control
valve
See
Fuel
injection
Ignition
switch
See
Switches
and
electrical
accessories

INDEX
5