1994 BMW 325i Wiring

Fig
.
9
.



Fuel
pump
relay
terminal
identification
.

Fuel
Pump
Electrical
Tests

Troubleshooting
of
any
fuel
pump
fault
should
begin
with

checking
the
fuel
pump
fuse
and
the
fuel
pump
relay
.
The
DME
main
relay
should
also
be
checked
.

NOTE-

Special
tools
are
requíred
for
some
of
the
tests
de-
scribed
here
.

Fuel
pump
electrical
circuit,
testing

The
fuel
pump
electrical
circuit
diagram
is
shown
in
Fig
.
10
.

3
.
If
fuel
pump
does
not
run,
disconnect
black
harness

connector
from
tank
sender
unit
.
With
jumper
wire
con-

nectedas
described
in
step
2
above,
check
for
positive

(+)
batteryvoltage
at
harness
connector
terminals
.
See
Fig
.
11
.

FUEL
TANK
AND
FUEL
PUMP



160-
7

From
Main
Relay
(+15
power
with
key
in
run



From
B+juretion
point
orstartposition)
(batteryvoRageatalltirnes)

'
.5
RD/Nrr



1
.5
RD

1
.5
GNNI

From
Engine



2
.5
GNNI
Control
Module



15
2
.5
GNNI

Ground
(below
center
console)

Fig
.
10
.
Fuel
pump
electrical
circuit
.

30

-~
Relay
Fuel
Pump

8~T

I



1

s
ám
61
Front
Power
I



a
1
Distribution
Box
I_
16

WIRING
COLOR
CODE

BK
-
BLACK
BR
-
BROWN
Fuel
Pump



RD



-



RED
(in-tank)
M
YL
YELLOWGN
-
GREENBU
-
BLUE
1
VI
-
VIOLET
GY
-
GREY
WT
-
WHITE
PK
-
PINK

0011946

4
.
If
voltage
and
groundare
present,
fuel
pump
is
proba-
bly
faulty
.
If
there
is
no
voltage,
check
wiring
From
fuel
pump
Reay
and
make
sure
Reay
is
functioning
correctly
.

CAUTION-

Fuseandrelaylocationsmayvary
.
Usecara
when



Fuel
pump
power
consumption,
testing

troubleshooting
the
electrical
system
at
the
fuselrelay
panel
.
To
resolve
problems
in
identify-



NOTE-
ing
a
relay,
see
en
authorízed
BMW
dealer
.



"
To
achieveaccurate
testresults,
fhe
battery
voltage
at
the
connector
should
be
approximately
13
volts
.
1.
Remove
rearseat
cushion,
pull
right
side
insulation
mat



Charge
the
battery
asnecessary
.

back
to
expose
fuel
tank
accesscover
.
Remove
cover



.
q
higher
than
normal
power
consumption
usually
fin-
to
expose
wiring
connections
.



dicates
a
worn
fuel
pump,
which
may
cause
intermit-
tentfuel
starvation
due
lo
pump
overheating
and
2
.
Remove
fuel
pump
relay
and
opérate
fuel
pump
as
de-



seizure
.
The
only
remedy
is
pump
replacement
.
Be
scribed
under
Operating
fuel
pump
for
tests
earlier
.



sure
to
check
that
thereturn
fine
and
the
pump
pickup
Pump
should
run
.
Disconnect
jumper
wire
when
fin-



are
not
obstructed
before
replacing
the
pump
.

ished
.
1
.
Remove
rear
seat
cushion,
pull
right
side
insulation
mal
back
to
expose
fuel
tank
accesscover
.
Remove
cover
to
expose
wiring
connections
.

2
.
Disconnect
(black)
harness
connector
from
fuel
pump
.

3
.
Connect
an
ammeter
and
an
insulated
jumper
wire
be-

tween
terminals
in
connector
and
corresponding
pump

terminals
.
See
Fig
.
12
.

FUEL
PUMP

170-
4



RADIATOR
AND
COOLING
SYSTEM
A
quick
testat
the
coolant
temperature
gauge
sender
can



The
auxiliary
cooling
fan
comes
on
when
coolant
tempera

determine
if
the
gauge
is
functioning
correctly
.



ture
exceeds
a
predetermined
leve¡
or
whenever
the
air
condi-

tioning
is
on
.
A
dual-range
temperature
switch
for
cooling
fan
lf
the
gauge
needie
remains
at
the
rest
position
with
theen-



control
is
mounted
on
the
right
side
of
the
radiator
.
See
Fig
.
3
.
gine
warm,
remove
the
harness
connector
from
the
sender
and
jumper
the
correct
terminals
in
the
connector
to
simulate
a
high
engine
temperature
.
See
Table
a
.
Turn
the
ignition
on
.

If
the
gauge
needle
moves
upward,
the
sender
is
faulty
.
If
the

gauge
does
not
respond,
the
wiring
to
the
gauge
is
broken
(open
circuit)
or
the
gauge
itselfis
faulty
.

WARNING
-

1996
and
laten
models
are
OBD
11
compliant
.
Dis-
connecting
electrical
connectors
wíth
the
ignition
turned
on
may
set
fault
codes
in
the
ECM
.
It
is
rec-
ommended
that
you
leave
the
diagnosis
of
faults
in
the
coolant
temperature
sensorsystem
to
the
BMW
dealer
service
department
which
has
specialized
OBD
11
scan
tool
equipment
.

If
the
gauge
needle
reads
too
high
when
the
engine
is
cold,
remove
the
harness
connector
from
the
sender
.
Turn
the
igni-

tion
on
.
lf
the
gauge
needle
position
does
not
change,
the
wir-

ing
or
the
gauge
is
shorted
to
ground
.
If
the
gauge
needle

drops,
the
sender
is
faulty
and
should
be
replaced
.
When
re-

placing
a
faulty
coolant
temperature
sender,
the
gasket
ring
on
the
sender
should
also
be
replaced
.

Tightening
Torque

"
Temperature
gauge
sender
to
engine
18
Nm
(13
ft-Ib)

Cooling
fan,
testing

NOTE-

OnM44
engines
with
manual
transmission,
the
primary
electric
cooling
fan
is
mounted
on
the
engine
side
of
the
radiator
and
is
controlled
by
the
engine
control
module
(ECM)
.
Troubleshooting
thiscircuit
should
be
left
to
an
authorized
BMW
dealer
with
the
proper
diagnostic
equipment

An
otherwise
sound
cooling
system
may
still
overheat,
par-
ticularly
with
prolonged
idling,
due
to
a
failure
of
the
coolíng

fan(s)
.

The
belt-driven
cooling
fan
is
controlled
by
a
temperature
dependent
viscous
clutch
.
A
failed
fan
clutch
may
affect
air
flow
through
the
radiator
resulting
in
overheating
orpossibly
overcooling
.
Speed

Low
sp
High
s

With
the
engine
off,
check
thefan
clutch
by
spinning
thefan
.



eed
The
fan
should
spin
on
the
clutch
with
some
resistance
.



peed
Check
for
signs
of
leaking
fluid
from
the
clutch
.
If
thefan
free-
wheels
with
no
resistance,
cannot
be
tu
rned
by
hand,
or
there
are
signs
of
oil
leakage,
the
clutch
should
be
replaced
.

TROUBLESHOOTING

Fig
.
3
.



Radiatorcooling
fan
temperature
switch
(arrow)
.

WARNING
-

"
Use
caution
when
testing
the
electric
cooling
fan(s)
and
coolant
temperature
switch
.
Keep
hands
and
wires
clear
of
thefan
blades
.
The
cool-
ing
fan(s)
can
run
any
time
the
ignition
is
ON
.

"
For
greatest
safety,
coolíng
fan
and
coolant
tem-perature
switch
tests
shouldbe
performed
on
acoldengine
with
the
air
conditioning
off
.

Table
b
.
Auxiliary
Cooling
Fan
Switching

Temperatures

Switching
temperature
196°F(91°C)
210°F(99°C)

0012506

If
a
faulty
thermostat,
trapped
air,
or
a
restriction
in
the
sys-
tem
is
not
allowing
the
coolant
to
circulate
through
the
radia-
tor,
the
temperature
switch
will
not
close
and
the
auxiliary
cooling
fan
will
not
run
.
Before
making
the
tests
described
be-
low,
make
sure
the
thermostat
is
operating
correctly
as
de-
scribed
earlier
.
The
normal
switching
temperatures
for
the

dual
-speed
switch
are
listed
in
Table
b
.

NOTE-

Some
cars
covered
by
this
manual
may
have
an
alter-
nate
cooling
fan
switchwith
switching
temperatures
of
176%190W
(80%88°C)
.
When
replacing
the
switch
check
theswitching
specifications,
whichshouldbe
stamped
on
the
switch
body
.

1
.
If
coolant
is
circulating
at
normal
operating
tempera-
ture,
but
auxiliary
cooling
fan
does
not
run,
disconnect
connector
from
radiator
temperature
switch
and
make
tests
listed
in
Table
c
.

Table
c
.
Auxiliary
Cooling
Fan
Temperature

Switch
Tests

Wires
jumpered



Test



Test
resuits
conditions

Black/green
(terminal2)
and



Ignition
ON



Fan
runs
on
brown
(terminal
1)



low
speed

Black/gray
(terminal
3)
and



Ignition
ON



Fan
runson
brown
(terminal



I
1)



high
speed
2
.
If
fan
runs
only
when
powered
directly
by
jumpered
connector
and
hot
coolant
is
circulating
through
radia-
tor,
radiator
temperature
switch
is
most
likelyfaulty
.
Use
a
new
sealing
ring
when
replacing
switch

Tightening
Torque

"
Temperature
switch
to
radiator
......
15
Nm
(11
ft-Ib)

3
.
If
auxiliary
fan
does
notrun
when
powered
directly,
check
for
battery
voltage
at
temperature
switch
connec-
tor
(black/green
wire)
with
ignition
on
.
If
battery
voltage
is
not
present,
check
fuses
.
See
610
Electrical
Com-
ponent
Locations
.

RADIATOR
AND
COOLING
SYSTEM



170-
5

~r~nmm
a
00
0

Fig
.
4
.



Auxiliary
radiator
cooling
fan
low
speed
relay
(1)
and
high
speed
relay
(2)
in
power
distribution
box
.
(Relay
locations
may
vary
.)

Auxiliary
Cooling
Fan
Circuit
Fuses



Fig
.
5
.
Auxiliary
radiator
fan
resistor
(arrow)
.
"
Fuse16
.
...................
..
..
...
...
.5
amp

"
Fuse
41
(ex
.
M44
w/man
.
trans)
.
..
.
..
.....
30
amp

"
Fuse
48
(M44
w/man
.
trans
.
only)
..
.
..
.....
40
amp



COOLING
SYSTEM
SERVICE

0013034

4
.
If
no
faults
are
found,
remove
low
speed
relay
and
turn



Coolant,draining
and
filling

ignition
ON
.
See
Fig
.
4
.



1
.
Remove
expansion
tank
cap
.
Set
temperature
controls
"
Check
for
power
at
terminal
30
and
terminal
86
of
relay



to
full
warm
.
socket
.

"
Reinstall
low
speed
relay
and
repeat
testat
high
speed



WARNING
-
relay
socket
.
Fix
any
wiring
faults
found
.



Allow
the
cooling
system
to
cool
before
openlng
or

On
early
productioncars
(up
to
9/92)
:
If
fan
operates
only
on



draining
the
cooling
system
.

high
speed
and
no
electrical
faults
have
been
foundup
to
this
point,
usean
ohmmeter
to
check
that
fan
resistor
is
not
electri-



2
.
Place
3
ra
allo

ug
.



beneath
radiator
drain
plug
and
re-

cally
open
.
Resistor
is
mounted
on
auxiliary
cooling
fan
housing



move
drain
plg
.
See
Fig
.
6
.

behind
front
grille
.
See
Fig
.
5
.
Wiring
diagrams
for
the
radiator

cooling
fan
canbefoundunder
Electrical
Wiring
Diagrams
.



3
.
Place
3-g



pail
beneath
rear
of
engine
blo
.
Loos-
en
and
re

mlon

ove
engine
blockcoolant
drain
plug
k
.

COOLING
SYSTEM
SERVICE

Fig
.
13
.
Version
2
auxiliary
fan
mounting
screws
(arrows)
.
Front
bumper
hasbeen
removed
.

4
.
Installation
is
reverse
of
removal
.

Thermostat,
replacing

0013146

The
coolant
thermostat
is
instalied
in
a
housing
at
the
front

of
the
cylinder
head
.
See
Fig
.
14
.

Fig
.
14
.
Coolantthermostat
and
housíng
.

NOTE-

On
M44
engines,
the
thermostat
is
integrated
into
the
thermostat
housíng
.
If
the
thermostat
requiresreplace-
ment,
the
complete
thermostathousing
mustbe
replaced
.

RADIATOR
AND
COOLING
SYSTEM



170-
9

WARNING
-

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

2
.
Remove
belt-driven
cooling
fan
and
fan
shroudas
de-

scribed
earlier
.

3
.
On
M52/S52US
engines
:
Unclip
wiring
duct
retaining
clips
and
remove
duct
from
above
thermostat
housing
.

Also
remove
engine
front
lifting
bracket
.

4
.
Remove
thermostat
housing
from
front
of
engine
.
See
Fig
.
15
.

Fig
.
15
.
Thermostat
housíng
shown
removed
(6-cylinder
engine)
.

NOTE-

Some
thermostats
have
a
direction
arrowor
venthole
near
the
edge
.
Install
the
thermostat
so
that
either
the
arrow
or
hole
are
at
thetop
.

CAUTION
-

Be
sure
to
reconnect
ground
wire(s)
at
thermostat
housing
mounting
bolt,
where
applicable
.

5
.
Remove
thermostat
.
Note
thermostat
direction
and
ori-

entation
before
removing
.

6
.
Insta¡¡
new
thermostat
and/or
thermostat
housing
using

new
O-ring
and
gasket(s)
as
necessary
.

oo131ss



7
.
Installation
is
reverseof
removal
.
Fill
system
with
cool-

ant
as
described
under
Coolant,draining
and
filling
.

Tightening
Torques

1
.
Drain
radiator
as
described
above
under
Coolant,



"
Thermostat
housing
cover

draining
and
filling
.



to
housing
orcoolant
pump
..
..
....
10
Nm
(89
in-lb)

"
Engine
lifting
bracket
bolt
to
thermostat
housing

(M52/S52US
engine)(M8)
....
..
...
22
Nm
(17
ft-Ib)

COOLING
SYSTEM
SERVICE

8
.
Disconnect
main
harness
connector
from
transmission

by
turning
its
bayonet
lock
ring
counterclockwise
.
Re-

move
wiring
harness
from
transmission
housing
.
See
Fig
.
8
.

Fig
.
8
.



Harness
connector
at
automatic
transmission
.

9
.
Where
applicable,
disconnect
harness
connector
from

speed
sensor
at
top
óf
transmission
.

10
.
Disconnect
transmission
cooler
line
clamps
from
en-

gine
.
Disconnect
lines
from
transmission
.

11
.
Support
transmission
with
transmission
jack
.
Remove

reinforcing
cross
brace
(if
applicable)
and
transmission

support
crossmember
.

NOTE-

Note
installation
positionof
support
crossmember
.

12
.
Remove
access
plug
in
cover
plate
on
right
side
of
en-

gine
block
and
remove
torqueconverter
bolts
.
Turn

crankshaft
to
access
boits
.
See
Fig
.
9
.

AUTOMATIC
TRANSMISSION



240-
5

Bellhousing
access
hole

Socket
wrench

Fig
.
9
.



Access
andremove
torque
converter
boits
through
hole
in
bellhousing
cover
.

0

A

fij
13
.
Remove
bellhousing-to-engine
mounting
bolts
.
See



Fig
.
10
.
Transmission-to-engine
Torx-head
mounting
bolts
.
Fig
.
10
.

0012592

TRANSMISSION
REMOVAL
AND
INSTALLATION

Fig
.
10
.
Align
contact
slide
(1)
with
slot
in
switch
housing
(2)
before
in-
stalling
gear
position/neutral
safety
switch
.

Fig
.
11
.
Engage
release
button
pin
to
hole
in
pull
rod
before
installing

The
automatic
shiftlock
uses
an
electríc
solenoid
to
lock
the
selector
lever
in
P
or
N
.
Depressing
the
foot
brake
withthe
ig-
nition
on
energizes
the
solenoid,
allowingthe
lever
to
be
moved
into
a
drive
gear
.
The
solenoid
is
energized
only
when

the
engine
speed
is
below
2,500
rpmand
thevehicle
speed
is

below
3
mph
.
The
solenoid
ís
mounted
in
the
right-hand
side

of
theselector
lever
housing
.
See
Fig
.
12
.

1
.
With
engine
running
and
car
stopped,
place
selector
le-
ver
in
P
or
N
.

2
.
Without
depressing
brake
pedal,
check
that
selector
le-

ver
is
locked
in
position
P
or
N
.

3
.
Depress
brakepedal
firmly
.
Solenoid
should
be
heard

to
energize
.

GEARSHIFT
LINKAGE



250-
5

Fig
.
12
.
Automatic
shiftlock
prevents
drive
gear
selection
until
the
brakepedal
is
depressed
.

4
.
Check
thatselector
lever
can
now
be
moved
out
of
P
or
N
.

NOTE
-

The
next
test
should
be
performed
in
anopen
area
with
the
parking
brake
on
and
with
extreme
caution
.

5
.
With
selector
lever
in
P
or
N
and
brake
pedal
de-

pressed,
raise
engine
above
2,500
rpm
.
Check
that
se-

lector
lever
cannotbe
moved
outof
P
or
N
.

shift
lever
handle
.



If
any
faults
are
found
check
the
electrical
operation
of
the
shiftlock
solenoid
and
check
for
wiring
faultsto
or
from
the
Automatic
shiftiock,
checking
function



transmission
control
module(TCM)
.
See610
Electrical

(automatic
transmission)



Component
Locations
and
Electrical
Wiring
Diagrams
.

NOTE
-

The
solenoid
is
controlled
viathe
TCM,
using
brakepedal
position,
engine
speed,
and
road
speed
as
con-
trolling
inputs
.

AUTOMATIC
TRANSMISSION
GEARSHIFT

Fig
.
6
.



Preload
center
bearing
toward
front
4-6
mm
(arrow)
.

5331
5
.
Tightenthreadedsleeveondriveshafttopropertorque
.

6
.
Insta¡¡
heat
shield
and
heat
shield
crossmember
.

Tightening
Torques

"
Driveshaftcenter
mount
to
body
.
.
..
21
Nm
(16
ft-Ib)

"
Driveshaft
clamping
sleeve
.....
.
.
.
10
Nm
(89
in-lb)

"
Driveshaft
to
final
drive
flange

With
CV
joint
(M8)
............
...
32
Nm
(23
ft-Ib)

Wth
U-joint
(M10
ribbed
nut)
....
...
80
Nm
(59
ft-Ib)

With
U-joint
(M10
compressed
nut)
..
60
Nm
(44
ft-Ib)

"
Flex-disc
to
driveshaft
or
transmissionflange

M10
(8.8
grade)
.........
.
....
..
.
48
Nm
(35
ft-Ib)

M10
(10
.9
grade)
........
.
....
...
64
Nm
(47
ft-Ib)

M12
(8.8
grade)
........
.....
..
.
.
81
Nm
(60
ft-Ib)

M12
(10
.9
grade)
.
.
....
......
...
100
Nm
(74
ft-Ib)

M12
(10
.9
grade)
(M3
models)
..
.
.
.
115
Nm
(85
ft-Ib)

"
Transmission
crossmember

to
body
(M8)
.
....
...........
....
21
Nm
(16
ft-Ib)

NOTE-

Bolt
grade
is
markedon
the
bolt
head
.
When
replacing
bolts,
only
use
bolts
of
the
same
strength
and
hardnessas
the
originalsinstalled
.

Flex-disc,
replacing

The
flex-disc
between
the
front
section
of
the
driveshaft
and

theoutputflange
of
the
transmission
should
be
checked
for

cracks,
tears,
missing
pieces,
or
distortion
.
Check
for
worn
bolt
hole
bores
in
theflange
.

1
.
Remove
driveshaft
as
described
in
Driveshaft,
remov-
ing
.

NOTE-

¡t
is
possible
to
only
partially
remove
the
driveshaft,
leaving
it
connected
to
the
final
drive
.
The
driveshaft
canbe
tilted
down
in
thecenter
and
slidoff
the
trans-
mission
flange
once
the
clamping
sleeve
is
loosened
and
the
center
bearing
bracket
is
unbolted
.
Suspend
the
driveshaft
using
stiff
wire
in
as
close
to
the
installed
position
as
possible
.
If
the
driveshaft
hangs
unsupport-
ed,
the
rear
universal
joint
may
be
damaged
.

2
.
Unbolt
flex-dísc
from
driveshaft
.

DRIVESHAFT
260-
5

7
.
Install
exhaust
system
.
See
180
Exhaust
System
.

Connect
wiring
harness
to
oxygen
sensors
.



NOTE-

Removaland
installation
of
the
boltsmaybe
made
eas-
8
.
Road
test
vehicle
to
check
for
noiseor
vibration
.



ier
by
placing
a
large
hose
clamp
around
the
flex-disc,
and
tightening
the
clamp
slightlyto
compress
the
cou

WARNING
-



pling
.

"
Do
not
reuse
self-locking
nuts
.
These
nuts
aredesigned
to
beused
only
once
.



3
.
Insta¡¡
new
flex-disc
using
new
self-locking
nuts
.
Mold-

"
Avóid
stressing
the
flex-disc
when
torquing
the



ed
arrows
on
coupling
should
face
flange
arms
.
See

bolts
Do
this



holding
the
bolts



Fig
.
7
.
steady
and
.



uy
turning
the
nuts
on
theflange
side
.

5
:132

Fig
.
7
.



When
attaching
flex-disc,
molded
arrows
must
point
toward

flange
arms
.

DRIVESHAFT
SERVICE

330-
1
0



REAR
SUSPENSION

Trailing
arm,
removing
and
installing

1
.
Raise
rear
end
of
car
and
remove
wheel
.

WARNING
-

Make
sure
that
the
car
is
firmly
supported
on
jack
standsdesigned
for
the
purpose
.
Place
the
jack
standsbeneatha
structural
chassis
point
.
Do
not
place
jack
stands
under
suspension
parts
.

2
.
Remove
drive
axle
as
described
earlier
.

3
.
Remove
brake
rotor
and
caliper
as
described
in
340

Brakes
.
Do
not
remove
brake
line
from
caliper
.
Hang

caliper
from
body
with
wire
.

4
.
Remove
parking
brakecable
frombrake
shoe
expand-

er
.
See
340
Brakes
.

5
.
Remove
rear
brake
line
bracket
from
trailing
arm
.
See

Fig
.
17
.

Fig
.
17
.
Brake
line
bracket
bolts
on
trailing
arm
(arrow)
.

WARNING
-

It
is
recommended
that
a
restraining
chain
be
in-
stalled
between
the
bottom
coil
of
the
coil
spring
and
the
upper
control
arm
to
retainthe
spring
in
case
of
accidentalrelease
.
Personal
injury
can
re-sult
if
the
compressed
coil
spring
is
not
released
slow1y
and
carefully
.

REAR
SUSPENSION
ARMS

6
.
Support
trailing
arm
from
below
with
a
transmission
jackorequivalent
.

7
.
Remove
shock
absorber
to
trailing
arm
bolt
.
See
Fig
.
18
.
Slowly
lower
suspension
until
coil
spring
can
be
safely
removed
.

0013220

Fig
.
18
.
Support
trailing
arm
before
removing
lower
shock
bolt
(ar-

row)
.

8
.
Unbolt
upper
and
lower
control
arms
from
trailing
arm,

as
described
later
.

9
.
Remove
ABS
wheel
speed
sensor
from
rear
wheel

bearing
housing
.
Unclip
sensor
wiríng
from
trailing
arm
.

If
removing
right
trailing
arm,
separate
brake
pad
wear

sensor
connector
.
See
Fig
.
19
.

0012104

Fig
.
19
.
Brake
pad
wear
sensor
and
ABS
wheel
speed
sensor
con-
nectors
(arrow)
.

10
.
Remove
three
bolts
holding
trailing
arm
front
bracket
to
body
.
See
Fig
.
20
.
Remove
trailing
arm
.