EVAP BMW 328i 1997 E36 User Guide

Table
I
.
ECM
Pin
Assignment-Siemens
DME
MS
41
.1
(continued)

Pin



I
Signal



I
Component/function



1
Signal

FUEL
INJECTION



130-
37

47
-

48



input



Crankshaft
position
sensor
(Hall
effect)



Crankshaft
position
sensor
control

49



input



Power
supply
(terminal
15)



Batteryvoltage
with
key
onor
engine
running
50



output



Solenoid
valve
(running
losses)



Running
losses

51



output



Carbon
canister
valve



Carbon
canister
valve
control

52vacant
-

53



output



Idle
speed
control
valve



Pulsed
ground-close
signal
(seealsopin29)
54



input



Power
supply



Battery
voltagefrom
main
relay
(terminal
87)

55
vacant
-

56
-

57



input



Knock
sensor
(cyl
.
1-3)



Knock
sensor
input
Signal

58



output



Knock
sensor
(cyl
.
1-3)



Knock
sensor
control

59



input



Knock
sensor
(cyl
.
4-6)



Knock
sensor
input
Signal

60



input/output



Diagnostic
connector
(TxD)



Diagnostic
TxD
(transmit)
signal
to
pin
18
in
Data
link
connector
61



output



Oxygen
sensor
heater
(monitoring
sensor)



Oxygen
sensor
heater
ground

62



output



Secondary
air
injection



Secondary
air
injection
control
valve

63



output



Knock
sensor
(cyl
.
4-6)



Knock
sensor
control

64



input



Camshaft
position/rpm
sensor



Camshaft
position/rpm
sensor
control

65



input



Camshaft
position/rpm
sensor



Camshaft
position/rpm
sensor
control

66
-

67



output



Oxygen
sensor



Oxygen
sensor
reference
voltage

68



output



Evaporative
purge
valve
control



Pulsed
ground
with
engine
at
normal
temperature
and
varyingengine
load

69



output



Fuel
pump
relay
control



Fuel
pump
relay
switches
with
engine
runningorcranking
(crankshaft
position
signal
must
be
present
for
relay
switchover)

70
vacant
-



-

71



output



Oxygen
sensor
heater
(regulating
sensor)



Oxygen
sensor
heater
ground

72



output



Oxygen
sensor
(monitoring
sensor)



Oxygen
sensor
referencevoltage

73



input



Main
relay
control



Main
relay
activation
(terminal
85)

74



output



A/C
compressor
control



A/C
compressor
relay
control

75



input



Oxygen
sensor



Oxygen
sensor
signal

76



not
used



-



-

77



input



Oxygen
sensor
(regulating
sensor)



Oxygen
sensor
signal

78



input



Oxygen
sensor
(monitoring
sensor)



Oxygen
sensor
signal

79



output



Oxygen
sensor
(regulating
sensor)



Oxygen
sensor
referencevoltage

80



Traction
control



AST
module

81



Traction
control



AST
module
82



Traction
control



AST
module
83



output



Crankshaft
position
sensor
(Hall
effect)



Crankshaft
position
sensor
control

84
vacant
-



-

85



output



Automatic
transmission



Automatic
transmission
control
module

86



input



Automatic
transmission



Automatic
transmissíon
control
module

87



input



Power
supply



Battery
voltage
from
main
relay
(terminal
87)

88



input/output



Diagnostic
connector
(TxD)



Diagnostic
TxD
(transmit)
signal
to
pin
17
in
Data
link
connector

ECM
PIN
ASSIGNMENTS

160
Fuel
Tank
and
Fuel
Pump

GENERAL
.
.
.
.
.
.
...........
.
....
.
.
.
.
.
.
160-1



Operating
fuel
pump
for
tests
.
.
.
.
.
.
.......
.160-6

Fuel
Pump
Electrical
Tests
.
.
.
.
.
.
.
...
.
.
.
.
.
160-7

FUEL
TANK
AND
LINES
..
.
.
.
..........
160-2



Fuel
pump
electrical
circuit,
testing.
...
.
.
.
.
.
160-7

Fuel
tank,
draining
..
.
.
.
.
.
.
.
.
.
..........
160-2



Fuel
pump
power
consumption,
testing
.
.
.
.
.
.
160-7

Fuel
tank,
removing
and
installing
.........
160-3



Fuel
Delivery
Tests
....
.
.
.
...
.
.....
.
.
.
..
160-8

Fuel
Tank
Evaporative
Control
System
.....
160-4



Relieving
fuel
pressure
and
connecting

fuel
pressure
gauge
..
.
...........
.
.
.
..
160-8

FUEL
LEVEL
SENDERS
.
.
.
.
.
.......
.
.
.
160-4



System
pressure,
testing
.................
160-9

Fuel
level
senders,
testing
.
.
.
.
.
.......
.
.
.
160-5



Fuel
delivery
volume,
testing
.............
160-10

Fuel
leve¡
sender
and
fuel
pump
(right
side),
emoving
and
installing
.
.
.
.
.
.
160-5



TABLES

Fuel
leve¡
sender
(left
side),



a
.
FuelLeve¡
Sender
Resistances
...........
.
.
..
.160-5

removing
and
installing
.........
.
.
.
.
.
.
.
160-6



b
.
Fuel
Pump
Current
...
.................
..
...
160-8

c
.
Fuel
Pressure
Specifications
..............
.
..
160-10

FUEL
PUMP
.
.
.
................
.
.
.
.
.
.
.
160-6



d
.
Fuel
Pump
Delivery
Specifications
.........
.
..
160-10

Fuel
Pump
Fuse
and
Relay
.
.
.
....
.
.
.
.
.
.
.
160-6

GENERAL

This
repair
group
covers
service
information
specifically
for



The
cautions
and
warnings
on
this
page
should
beob
the
fuel
supply
system
.
Information
on
the
fue¡
injection
sys-



served
when
servicing
the
fuel
system
.
tem
is
covered
in
130
Fuel
Injection
.

NOTE-

Fue¡
filter
replacement
is
covered
in
020
Maintenance
Program
.

WARNING
-

"
The
fuel
system
is
designed
to
retain
pressure
even
when
the
ignition
isoff
.
When
working
with
the
fuel
system,
loosen
the
fuel
lines
slowly
toal-
low
residual
fuel
pressure
to
dissipate
gradually
.
Avoid
spraying
fuel
.

"
Before
beginning
any
work
on
the
fuel
system,
place
a
tire
extinguisher
in
the
vicinity
of
the
work
area
.

"
Fuel
is
highly
flammable
.
When
working
around
fuel,
do
not
disconnect
any
wires
that
could
cause
electrical
sparks
.
Do
not
smoke
or
work
near
heaters
or
other
tire
hazards
.

"
Always
unscrew
the
fuel
tank
cap
to
release
pres-
sure
in
the
tank
before
working
on
the
tank
or
fines
.

"
Do
not
use
a
work
light
near
any
fuel
.
Fuel
may
spray
onto
the
hot
bulb
causing
a
tire
.

"
Make
sure
the
work
area
is
properly
ventifated
.

FUEL
TANK
AND
FUEL
PUMP



160-1

CAUTION-

"
Prior
to
disconnecting
the
battery,
read
the
bat-tery
disconnection
cautions
given
at
the
front
of
this
manual
onpage
viü
.

"
Before
making
any
electrical
tests
with
the
ignition
tumed
on,
disable
the
ignition
system
as
de-
scribed
in
120
Ignition
System
.
Be
sure
the
bat-tery
is
disconnected
when
replacing
components
.

"
To
prevent
damage
to
the
ignition
system
or
the
electronic
fuel
system
components,
including
the
control
unit,
aiways
connect
and
disconnect
wires
and
test
equipment
with
the
ignition
off
.

"
Cleanliness
is
essential
when
working
with
the
fuel
system
.
Thoroughly
clean
the
fuel
fine
unionsbefore
disconnecting
any
of
the
fines
.

"
Use
only
clean
tools
.
Keep
removed
parts
clean
and
sealed
or
covered
with
a
clean,
lint-free
cloth,
especially
if
completion
of
the
repair
is
delayed
.

"
Do
not
move
the
car
while
the
fuel
system
is
open
.

"
Avoid
using
high
pressure
compressed
air
to
blow
out
fines
and
componente
.
High
pressure
can
rupture
infernal
seals
and
gaskets
.

"
Always
replace
seals
and
O-rings
.

GENERAL

160-2



FUEL
TANK
AND
FUEL
PUMP

0011943
1
.
Filler
pipe



10
.
Fuel
compensating
siphon
pump
and
hose
assembly
2
.
Filler
pipe
grounding
tab



(models
built
from
1/95)
3
.
Vent
pipe



11
.
Fueltank
4
.
Threaded
collar



12
.
Tank
support
strap
5
.
Rubber
ring
seal



13
.
Bolt-tighten
to
23
Nm
(17
ft-Ib)
6
.
Fuel
pump



14
.
Fuel
expansion
tank
7
.
Left
side
fuel
leve¡
sender(models
built
from
1/95)



15
.
Fuel
tank
pressure
sensor
(OBD
II)
8
.
Right
side
fuel
leve¡
sender9
.
Left
side
fuel
leve¡
sender
with
fuel
compensating
siphon
pump
(models
built
up
to
1/95)

Fig
.
1
.



E36
fuel
tank
assembly
.

FUEL
TANK
AND
LINES



Fuel
tank,
draining

The
plastic
fuel
tank
is
mounted
beneath
the
center
of
the
car
(beneath
rear
seat)
.
Mounted
in
the
fuel
tank
are
the
fuel
pump
and
fuel
leve¡
sending
units
.
Connecting
lines
for
the
evaporative
emission
control
systemand
expansion
tank
are
also
attached
to
the
tank
.
When
performing
the
procedures
that
follow,
refer
toFig
.
1
.

Fuel
tank
capacity
for
E36
modeis

"All
ex
.
1996
M3
(3
.0
L)
.....
.
..
..
65
liters
(17
.0
gal)

"
1996
M3
(3.0L)
modeis
.
...
.
..
.
.62
liters
(16
.4
gal)

FUEL
TA
NKAND
LINES

The
fuel
tank
should
be
drained
into
an
approved
storage
unit
or
another
car's
fuel
tank
.

WARNING
-
"
Before
removing
the
tank,
be
sure
that
afl
hot
components
such
as
the
exhaust
system,
are
completely
cooled
down
.

"
Fuel
may
be
spilled
.
Do
not
smoke
or
worknear
heaters
or
other
Pire
hazards
.

1
.
Disconnect
negative
(-)
cable
from
battery
.

CAUTION-

Prior
to
disconnectiog
the
battery,
read
the
battery
disconnection
cautions
given
at
the
front
of
this
manual
on
paga
vi¡¡
.

160-
4



FUEL
TANK
AND
FUEL
PUMP

Fig
.
4
.



Pinch
off
supply
and
retum
fuel
hoses
(arrows)
before
dis-
connecting
from
rigid
metal
lines
.

0013143

Fig
.
5
.
After
removing
exhaustsystem,
remove
heat
shield
screws
(arrows)
and
heat
shield
.

9
.
Working
underneath
car,
loosen
hose
clamp
and
dis-

connect
filler
hose
.

10
.
Support
tank
from
below
.
Remove
tank
strap
mounting

bolts
.
Lower
and
remove
tank,
disconnecting
right
side



TheE36
model
uses
a
two-lobed
fuel
tank
and
each
lobeof
vent
and
other
hoses/electrical
connectors
as
neces-



the
tank
has
its
own
fuel
level
sending
unit
.
sary
.

11
.
Installation
is
reverse
of
removal
.

"
Always
use
new
seals,
gaskets,
O-rings,
and
hose
clamps
.

"
Inspect
hoses
and
replace
any
that
are
chafed,
dried

outor
cracked
.

"
Inspect
heat
shield
and
replace
if
corroded
.

"
Inspect
rubber
buffers
and
liners
on
fuel
tank,
support
straps
and
on
underside
of
body
.
Replace
rubber

parts
that
are
hardened
or
damaged
.

FUEL
LEVEL
SENDERS

CAUTION-

"
Before
starting
the
engine,
fill
the
fuel
tank
with
at
least
1.5
gallons
(5
liters)
of
fuel
to
prevent

damaging
a
dry
fuel
pump
.

"
If
the
filler
neck
has
been
removed
from
the
body,
be
sure
toreattach
theneck's
grounding
screw
(where
applicable)
.
Check
electrical
resistance
between
the
ground
tab
and
wheel
hub
.
The
re-
sistance
shouldbeno
higher
than
0
.6
ohms
.

Tightening
Torques

"
Fuel
tank
to
body
.............
...
23
Nm
(17
ft-Ib)

"
Hose
clamps
(10
mm-16
mm
día
.)
..
2
.0
Nm
(18
in-lb)

Fuel
Tank
Evaporative
Control
System

The
fuel
tank
evaporative
control
system
is
used
to
vent
the

fuel
tank
to
a
charcoal
canister,
which
is
then
purgedby
en-

gine
vacuum
during
normal
engine
operatíon
.
This
controls

emission
of
raw
hydrocarbons
(fuel)
to
the
atmosphere
.
See

Fig
.
1
.

A
fuel
expansion
tank,
located
under
the
right
rear
fender,

traps
overflow
fuel
and
incorporates
extra
fuel
tank
plumbing
.

Startingwith
1996
models,
OBD
II
standards
require
that

the
fuel
tank
evaporative
control
system
be
monitored
for

leaks
.
This
is
accomplished
usingthe
fuel
tankpressuresen-

sor,
the
ventshut
off
valve,
and
the
evaporative
purge
valve
.

NOTE-

On
most
early
cars(1992-1995),
the
charcoal
canister

is
in
the
engine
compartment
.
On
latercars,
the
char-
coal
canister
is
under
the
spare
tire
in
the
luggage
com-
partment
.

FUEL
LEVEL
SENDERS

The
right
side
fuel
leve¡
sender
is
integrated
with
the
fuel

pump
.
Each
senderhas
a
float
connected
to
a
variable
resis-

tance
for
fuel
leve¡
.
When
replacing
the
sender/pump
assem-

bly
always
replace
hose
clamps,gaskets
and
O-rings
.

WARNING
-

When
removing
the
fuel
level
sender
or
the
fuel
pump,
the
fuel
tank
should
be
emptied
.

610-10



ELECTRICAL
COMPONENT
LOCATIONS

Component



Model
Year



Location



Refer
to

ABS
Hydraulic
Control
Unit



1992-1998



Left
rear
engine
compartment
undermaster
cylinder



Fig
.
7
.
Fig
.
10
.

ABS
Hydraulic
Control
Unit
Relay



1992-1998



Power
distribution
box



Fig
.
2
.

ABS
Pedal
Travel
Sensor



1992-1998



On
brake
booster
beside
master
cylinder



Fig
.
10
.

ABS
Relay



1992-1998



Power
distribution
box



Fig
.
2
.

ABS/AS
T
(Traction)
Control
Module



1992-1998



Behind
glove
compartment



Fig
.
8
.
Fig
.
9
.

ABS
Speed
Sensor,
Left
Front



1992-1998



Left
front
steering
arm



Fig
.
31
.
Wheel

ABS
Speed
Sensor,
Left
Rear



1992-1998



Left
rear
trailing
arm
Wheel

ABS
Speed
Sensor,
RightFront



11992-1998



Right
front
steering
arm
Wheel

ABS
Speed
Sensor,
Right
Rear



1992-1998



I
Left
rear
trailing
arm
Wheel
1

A/C
Compressor



1
1992-1998



(
Rightlower
frontof
engine

A/C
Compressor
Control
Relay



1
1992-1998
1992-1998
1992-1998

A/C
Control
Module

A/C
Evaporator
Temperature
Sensor
A/C
Pressure
Switch



1992-1998



Right
frontof
engine
compartment

A/C
Program
Switch



1992-1998



Center
of
dash
below
radio

A/CRecharging
Ports



1992-1998



Right
rear
engine
compartment



Fig
.
16
.

Air
Flow
Sensor



1992-1998



Between
throttle
housing
&
filter
housing



Fig
.
7
.

Airbag
Contact
Slip
Ring



1992-1998



Rear
ofsteering
wheel

Airbag,
Driver



1992-1998



In
center
of
steering
wheel



Fig
.
25
.

Airbag,
Passenger



1994-1998



Right
front
of
dash
above
glove
compartment



Fig
.
26
.

Airbag,
Side-Impact



1997-1998



Behind
right/left
front
door
panel
Airbag
Control
Module
(Basic)



1992-1993



Behind
glove
compartment



Fig
.
8
.
Fig
.
9
.

Airbag
Control
Module
(ZAE)



1994-1998



On
center
tunnel
under
rear
seat
cushion

Airbag
Crash
Sensor,
Airbag



1992-1993



On
righUleft
front
strut
tower
Airbag
Crash
Sensor,
Right/Left



1997-1998



Right/left
door
si¡¡
behind
front
seatSide
Impact

Alternator
(Generator)



1992-1998



Left
lowerfront
of
engine

Amplifier
Hi-fi



1992-1998



Left
front
side
of
luggage
compartment

Antenna
Amplifier
AM/FM



1992-1998



In
upper
left
side
C-pillar



Fig
.
27
.

COMPONENT
LOCA
TIONS

Table
a
.
E36
Component
Locations

Power
distribution
box



Fig
.
2
.

Behind
center
console

Left
sideof
heater
box

Continued

Tablea
.
E36
Component
Locations

Component



Model
Year



Location



Refer
to
Engine
Compartment
Light
Switch



1993-1996



Over
right
headlight
assembly



Fig
.
7
.

Engine
Control
Module
(ECM)



1992-1998



Right
rear
enginecompartment,
behind
bulkhead
panel



Fig
.
7
.

Engine
Control
Module
(System)



1992-1998



I
Power
distribution
box



Fig
.
2
.
Relay
Engine
Coolant
Leve¡
Sensor



1
1992-1998



1
Left
front
of
enginecompartment,
radiator
coolant
reservoir

Engine
Coolant
Temperature



1992-1998



I
Left
front
of
engine
under
intake
manifold



I



Fig
.
19
.
Sensor



Fig
.
20
.

Evaporative
Emission
Valve



1992-1998



Left
side
strut
Power
area

Evaporator
Temperature
Sensor



1992-1998



Left
side
of
heater
box

EWS
II
Control
Module



1/1995
-
1998



Behind
glove
compartment



Fig
.
8
.
Fig
.
9
.

EWS
II
Ring
Antenna



1
1/1995
-
1998
1
At
ignition
cylinder

EWS
II
Transmitter
Module



1/1995
-
1998



Right
side
of
steering
column
in
auxiliaryrelay
panel



Fig
.
3
.

Exhaust
Gas
Flap
Valve



1996-1998



Left
rear
muffler
area

Flasher
Relay



1992-1998



Power
distribution
box



Fig
.
2
.

Foglight
Relay



1



1992-1998



1
Power
distribution
box



1



Fig
.
2
.

Fresh
Air
FlapActuator



1



1992



1
Right
side
of
heater
box

Fresh
Air
FlapActuator



1
1993-1995



1
Below
right
side
heater
box

Fresh
Air
FlapActuator



1
1996-1998



Below
left
side
heater
box

Fuel
Injectors



1992
-
1998



Top
left
side
of
engine

Fuel
Leve¡
Sensor,
Left



1
1992-1998



/
Under
left
side
of
rear
seat
infuel
tank

Fuel
Leve¡
Sensor,
Right



1



1992-1998



1
Under
right
side
of
rear
seat
in
fuel
tank



1



Fig
.
28
.

Fuel
Pump



1



1992-1998



1



Under
right
side
of
rear
seat
in
fuel
tank



1



Fig
.
28
.

Fuel
Pump
Relay



1



1992-1998



1
Power
distribution
box



1



Fig
.
2
.

Fuel
Pump/Start
Identification
Relay



1994
-
1996



Power
distribution
box

Fuel
Tank
Pressure
Sensor



1
1997-1998



1
Right
rear
wheel
well
behind
trim
liner

ELECTRICAL
COMPONENT
LOCATIONS



610-13

Fuse
andRelay



x(Power



11992-1998



I
Left
side
of
engine
compartment



I



Fig
.
2
.
Distribution
Box



Fig
.
7
Fig
.
10
.

Gas
Filler
LockMotor



1992-1998



Right
side
of
luggage
compartment

Gear
Position/Neutral
Safety
Switch



1992-1998



Next
to
gear
shift
lever
in
center
console



Fig
.
29
.
(Automatic
Transmission
Range
Switch)

Glove
Compartment
Lock
Motor



1994-1998



Behind
glove
compartment

Grounds

G
100



1995-1998



Front
of
left
front
fender
(headlights)



Fig
.
22
.

G
101



1992-1998



Front
of
right
front
fender

Continued

COMPONENT
LOCATIONS

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
.

To
access
the
rear
window
blower
relay,
remove
the
glove
compariment
.
See
Fig
.
32
.

Fig
.
32
.
Rear
window
blower
relay
located
in
frontof
glove
compart-
ment
(arrow)
.

AIR
CONDITIONING

Thissection
covers
removal
and
installation
of
air
condition-

ing
refrigerant
components
.
A/C
testing
and
diagnosis,
refrig-

erantdischarge,
evacuatíon
and
recharge
are
not
covered

here
.

The
subassemblies
and
lines
of
the
air
conditionerare
filled

with
either
refrigerant
R12
(1992
cars)
or
R-134a
(1993
and

later
cars)
.
The
major
components
of
the
A/Csystem
are

shown
in
Fig
.
33
.

A/CSystem
Warnings
and
Cautions

WARNING
-

"
Always
be
careful
that
refrigerant
does
not
come
in
contact
with
your
skin
.
Always
wearhand
andeye
protection
(gloves
and
goggles)
when
work-

ing
around
the
AIC
system
.
If
refrigerant
does
come
in
contact
with
your
skin
oreyes
:
-Do
not
rub
skin
oreyes
;

-Immediately
flush
skin
oreyes
withcool
water
for
15
minutes
;
-Rush
to
a
doctor
orhospital
;
-Do
not
attempt
to
treat
yourself
.

"
Work
in
a
wefl
ventilated
area
.
Avoid
breathing
re-
frigerant
vapors
.
Exposure
may
irrítate
eyes,

nose,
and
throat
.
Switch
on
exhaustlventilation
systems
when
working
on
the
refrigerant
system
.

"
Do
not
expose
any
component
of
the
AIC
system
to
high
temperatures
(Above
80°Cl176°F)or

open
flames
.
Excessive
heat
will
cause
a
pres-

sureincrease
whichcould
burst
the
system
.

HEATING
AND
AIR
CONDITIONING



640-
1
1

0013015

WARNING
-

"
Keep
refrigerant
away
from
open
llames
.
Poison-
ous
gas
will
be
produced
if
it
bums
.
Do
not
smoke
near
refrigerant
gases
for
the
same
reason
.

"
The
AICsystem
is
filled
with
refrigerant
gas
which
is
under
pressure
.
Pressurized
refrigerant
in
the
presenceof
oxygen
may
forma
combusti-
ble
mixture
.
Never
introduce
compressed
air
finto
any
refrigerant
container
(full
or
empty),
capped
off
AIC
component,
or
piece
of
service
equip-
ment
.

"
Refrígerant
gases
are
heavier
than
air,
displace
oxygen
and
may
cause
suffocation
in
areas
of
poor
círculation,
for
example
under
a
car
.
Switch
on
exhaustlventilation
systems
when
working
on
the
refrigerant
system
.

"
State
and
local
governments
may
have
additional
requirements
regarding
air
conditioning
servic-
ing
.
Alwayscomply
with
state
and
local
laws
.

"
Electric
welding
near
refrigerant
hoses
causes
R-134a
to
decompose
.
Discharge
system
before
welding
.

CA
UTION
-

-As
of
January
1,
1992,
any
person
who
services
a
motor
vehicle
air
conditioner
must,
by
law,
be
properly
trained
and
certified,
and
use
approved
refrigerant
recycling
equipment
.
Technicians
must
complete
an
EPA-approved
recycling
course
to
be
certified
.

"
It
is
recommended
that
al¡
system
refrigerant
AIC
refrigerant
be
left
to
an
authorized
BMW
dealer
or
other
qualified
AIC
service
facility
.

"
Do
not
top
off
a
partially
charged
refrigerant
sys-
tem
.
Dischargesystem,evacuate
and
then
re-
charge
system
.

"
R-134a
and
R-12
refrigerants
and
refrigerant
oils
and
system
components,
including
hoses
and
sealing
O-rings,
are
NOT
compatible
.
Compo-
nent
damage
andlor
system
contamination
will

result
.

"
The
mixture
of
refrigerant
oil
(PAG
oil)
and
refrig-
erant
R-134a
attacks
some
metals
and
alloys
(for
example,copper)
and
breaks
down
certain
hose
materials
.
Use
only
hoses
and
lines
that
are
iden-
tified
with
a
green
mark
(stripe)
or
the
lettering
R-
134a"
.

"
Immediately
plug
open
connections
on
AIC
com-
ponents
to
prevent
dirt
and
moisture
contamina-
tion
.

"
Do
not
steam
clean
condensers
or
evaporators
.

Use
only
cold
water
or
compressed
air
.

AIR
CONDITIONING

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