airconditioning system BMW 325i 1994 E36 Workshop Manual
Page 383 of 759
NOTE
-
Sometimes
the
color
of
en
installed
wire
may
be
differ-
ent
than
the
one
on
the
wiring
diagram
.
Don't
be
con-
cerned
.
Just
be
sure
lo
confirm
that
the
wire
connects
lo
the
proper
terminals
.
Wire
color
codes
"
BLU
.........
.
..
..
...
.
.................
Blue
"
BRN
....:....
.
..
..
...
..
...............
Brown
"
YEL
.........
.
..
..
...................
.Yellow
"
GRN
.........
.
..
..
...
.
................
creen
"
G
RY
.......
.
.
.
..
..
.....................
G
ray
"
ORG
.........
.
..
..
...
.
..............
.Orange
"
RED
......
...
.
.
..
.....................
.Red
"
BLK
.........
.
..
..
...
.
................
Black
"
VIO
..........
.
..
...
..
..
.......
.
.......
Violet
"
WHT
.........
.
.
....
.
...
:..............
White
Table
a
.
Terminal
and
Circuit
Numbers
Number
1
Circuít
description
1
j
Low
voltage
switched
terminal
of
coi¡
4
1
High
voltage
center
termina¡
of
coi¡
+x
Originates
atignition
switch
.
Supplies
powerwhen
the
ignition
switch
is
in
the
PARK,
RUN,
or
START
position
15
Originates
atignition
switch
.
Supplies
powerwhen
ignition
switch
is
in
RUN
or
START
position
30
Battery
positive
(+)
voltage
.
Supplies
power
whenever
battery
is
connected
.
(Not
dependent
on
ignition
switch
position,
unfused)
31
1
Ground,
battery
negative
(-)
terminal
50
Supplies
power
from
battery
to
starter
solenoid
when
ignition
switch
isin
START
position
only
+54
Originates
atignition
switch
.
Supplies
power
when
ignition
switch
isin
the
RUN
position
only
85
1
Ground
side
(-)
ofrelay
coil
86
1
Power-in
side
(+)
ofrelay
coil
87
1
Relay
actuatedcontact
D
Alternator
warning
light
and
field
energizing
circuit
ELECTRICAL
SYSTEM-GENERAL
600-
3
Additional
abbreviations
shown
in
the
wiring
diagrams
are
given
below
.
Abbreviations
"
ABS
........
.
...
.
...
.
..........
antilock
brakes
"
A/C
........
.
...
..
..
.
.........
.airconditioning
"
AST/ASC+T
.......
...
.
.
.......
al¡
season
traction
"
CONV
.......
.
.
...
.................
convertible
"
DME
........
.
.
...
.......
digital
motor
electronics
"
ECM
.......
.
...
..
..
.
..
electronic
control
module
"
EWS/EWS
II
......
...
.
.
coded
driveaway
protection
"
SRS
........
.
supplemental
restraint
system-airbag
"
TCM
........
.
..
....
.
transmission
control
module
"
ZKE
(94-98
models)
..
..
.
...
central
body
electronics
"
ZVM
(92-93
models)
...
.
.
..
.
.......
central
locking
ELECTRICAL
TROUBLESHOOTING
Most
terminals
are
identified
by
numbers
on
the
compo-
nents
and
harness
connectors
.
The
terminal
numbers
for
ma-
Four
things
are
required
for
current
toflow
in
any
electrical
jor
electrical
connections
are
shown
in
the
diagrams
.
Though
circuit
:
a
voltagesource,
wires
or
connections
to
transport
the
many
terminal
numbers
appear
only
once,
severa¡other
num-
voltage,
a
load
or
device
that
uses
the
electricity,
and
a
con-
bers
appear
in
numerous
places
throughout
the
electrical
sys-
nection
to
ground
.
Most
problemscanbefound
using
a
digital
tem
and
identify
certain
types
ofcircuits
.
Some
of
the
most
multimeter
(volt/ohm/amp
meter)to
check
for
voltage
supply,
common
circuit
numbers
are
listed
below
in
Table
a
.
for
breaks
in
the
wiring
(infinite
resistance/no
continuity),
orfor
a
path
to
ground
that
completesthe
circuit
.
Electric
current
is
logical
in
its
flow,
always
moving
from
the
voltage
sourcetoward
ground
.
Electricalfaults
can
usually
be
located
through
a
process
of
elimination
.
When
troubleshoot-
ing
a
complex
circuit,
separate
the
circuit
into
smaller
parts
.
The
general
testsoutlined
below
may
be
helpful
in
finding
electrical
problems
.
The
information
is
most
helpful
when
used
with
the
wiring
diagrams
.
Be
sure
to
analyze
the
problem
.
Use
the
wiring
diagrams
to
determine
the
most
likely
cause
.
Getan
understanding
of
how
the
circuit
works
by
following
the
circuit
from
groundback
to
the
power
source
.
When
making
test
connections
at
connectors
andcompo-
nents,
use
care
to
avoidspreading
or
damaging
the
connec-
tors
or
terminals
.
Some
tests
may
require
jumper
wires
to
bypass
components
or
connections
in
the
wiring
harness
.
When
connecting
jumper
wires,
use
bladeconnectors
at
the
wire
ends
that
match
the
size
of
the
terminal
being
tested
.
The
small
interna¡
contacts
are
easily
spread
apart,
and
this
can
cause
intermittent
or
faultyconnections
that
can
leadto
more
problems
.
ELECTRICAL
TROUBLESHOOTING
Page 452 of 759
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
.
Page 618 of 759
BLOWER
RELAY
77720
b
GFN/=RN
6
GF
OFF
N/RED
1
,~7
BL~K
2
11
GEN
3
2
BLU
4
3
G~RN/BRN
BLOWERBWITCH
OFF
CLIMATE
OFF
HOTAT
HOTINRUN
HOTINRUN
HOTAT
HOT
AT
HOTATALLTIMEB--
ALLTIMES
OR
START
ORSTART
ALL
TIMES
ALLTIMES
.1
19
VIOIGRY
GRN/YEL
8
RED/YEL
Air
Conditioning
&
Heating
1995
318ti
GRYIRED
INTERIOR
LIGHTS
SYSTEM
ELECTRICAL
WIRING
DIAGRAMS
ELE-135
AIRCONDITIONING
COMPRESSOR
REDIGRN
B
BLU
2
REDIGRN
B
GRNIBLU
BLKIGRY
j
(NOTUBE
D)
D)
HIGH
SPEEO
RELAY
NORMAL
SPEED
RELAY
1)ABOVE99
DEGC
AUXILIARY
2)ABOVE
91
FAN
MOTORDEGC
I
BLK
2
BEN
1
BLK/GRN
2
TEMPERATURE
SWITCH
Page 620 of 759
87847
BLOWER
RELAY
6
GRN/BRN
.1
)2
GRNIBRN
B
CONTROL
SWITCH
GRY/RED
4
BRN
"BRN
+G202
RECIRC
RRDEFOG
INTEGRATEDHEATINGANDCLIMATECONTROL
MODULE
HOTAT
HOTINRUN
HOT
IN
RUN
HOTAT
HOT
AT
HOTATALLTIMES_
ALLTIMES
OR
START
_
__
_
ORSTART
ALLTIMES
ALLTIMES
r
71GNIT'ON
r
_
FU
_
SE
FUSE
FUSE
FUSE
FUSE
-
FRONT
POWER
I
S
WITCH
l
Box
I
I
I
20
23
18
39
41
BOXOFF
START
L
--_-
--5A-__
1
.5
=_--_
3
-_J
I
II
ACC
"
RUN
I
RED/YEL
EVAPORATOR
TEMPERATURE
SENSOR
Air
Conditioning
&
Heating
1997
318ti
BR=
'I
G201
,10
GRY/YEL
1
BRN
2
BRN
CLIMATE
CONTROL
S
WITCH
ILLUMINATION
ELECTRICAL
WIRING
DIAGRAMS
ELE-137
GRY/RED
DEFOGGER
SYSTEM
SOLID
S7A7E
WATER
FRESHAIR
TEMPERATURE
VALVE
COMPRESSORCONTROL
RECIRCULATIONMOTOR
WHEELSWITCH
RELAY
COMPRESSOR
BLU/BLK
BLKIGR
AIRCONDITIONING
BLKIBLU
_BLU
BRN
NORMALSPEEDRELAY
HIGH
SPEEDRELAY
1IABOVE88
DEGC
AUXILIARY
2)ABOVE80
FAN
MOTOR
DEG
C
BLK/GRN
3
+
.=N
1
L
----
'
+100
ABOVE
BLK
-
GRY
24
18BAR
BELOW
21
BAR
TEMPERATURE
SWITC
BELOW
15
BAR
ABOVE
2
.6
BAR
BELOW
ABOVE
1
.5
30BAR
BAR
PRESSURE
S
W
ITCH
BLK/
REDI
II
BB-K/
-
GRN
GRY
1
I
BlK/G
RV
85
I
I
VIO/G
RV
69
I
I
"
-LK/BLU
36,
I
I
L__I
ENGINE
CONTROL
MODULE
TRANSMISSION
CONTROL
MODULE