1994 BMW M3 relay

120-10



IGNITION
SYSTEM

Ground
(rear
of
engine
compartment,
rear
of
passenger
side
shock
tower)

.!
BK

Camshaft
Position
Sensor

IGNITION
SYSTEM
SCHEMATICS

Batteryvoltage
in
run
or
start
(
via
ignition
switch
terminal
15)

---------------------------------------------------------
55



S5154
i

power
input



Power
input



1
DME
Control
Module(Bosch
DME
M3
.1)

Ground
-
(RHrear
of
enginecompartment,
rearof
passenger
side
shock
tower)

Fig
.
15
.
Bosch
DME
M3
.1
usedon1992
M50
engines(without
VANOS)
.

.EBK

Crankshaftlrpm
Position
Sensor

5GN

1.0
RD

Ground
(RH
rearof
enginecompartment,
rear
of
passenger
side
shock
tower)

WIRING
COLOR
CODE

BK
-
BLACK
BR
-
BROWN
RD
-
RED
YL
-
YELLOWGN
-
GREEN
BL
-
BLUE
VI-
VIOLET
GY
"
GREY
WT
"
WHITE
PK
-
PINK

Batteryvoltage
in
run
or
start
(
via
main
relay
Battery
voltage



terminal
87)
in
run
or
start
(via
ignition
switch
terminal
15)

11508

1
grounds



Main
rela
control
P
ower
Input



Y



I
-
34
---"--
6
26
27
1

Battery
voltage
at
all
times
to
Main
relay
(terminal
85)

RER

Knock
Sensor
Knock
Sensor
(cyl
.1-3)
(cyl
.4-6)

Batteryvoltage



IMIRING
in
run
or
start



COLORCODE
(
via
ignition
switch
termina¡
15)



BK



BLAOK
BR
BROWN
RD
-
RED
YL
-
YELLOW
GN
"
GREEN
EL
-
BLUF
VI
-
VIOLET
GY
-
GREY
WT
-
WHITE
PK
-
PINK
4
.0
GN

l1/1j\
I'1
/~/1r1



l\r1

1
55



so



si



52



23



25



24



56



54
1
Power
input



Power
input



III



O
Engine
Control
Module
(Bosch
DMEM13
.1)



II



grounds



P
ower
input



Main
relaY
control
I
70
__
_
71



69



17



28



43



16



-34---"-6



26



27
____________________________________________

From
main
relaterminal
87
(battery
voltage
in
run
or
start

.5
YL

Camshaft
Position
Sensor

Ground
(RH
rearof
enginecompartment,
rear
of
shock
tower)

.5
BK

Crankshaft/rpm
Position
Sensor

Fig
.
16
.
Bosch
DME
M33
.1
ignition
system
círcuit
for
1993-1995
M50
engines
with
VANOS
.

IGNITION
SYSTEM



120-11

Ground
=
(RH
rear
of
engine
compartment,
back
sideof
shock
tower)

Batteryvoltage



Battery
voltage
in
run
or
start



in
run
or
start
(
via
ignition
switch



(
via
main
relay
terminal
15)



terminal
87)

1
.0
RD

11506a

.5
BR

Batteryvoltage
at
all
times
to
Main
relay
(terminal
85)

IGNITION
SYSTEM
SCHEMATICS

120-12



IGNITION
SYSTEM

Warning
.
Lethal
voltagepresent

Battery
voltage
in
run
or
start
(via
ignitíon
switch
terminal
15)

I
t

IGNITION
SYSTEM
SCHEMATICS

Battery
voltage
in
run
or
start
(
via
ignition
switchterminal
15)



WIRING
COLOR
CODE

Knock
Sensor
Knock
Sensor



Crankshaftlrpm



Camshaft
(cyl
.
1-3)



(cyl
.
4-6)



Position
Sensor



Position
-
-
Sensor
-

Fig
.
17
.
Siemens
MS
41
.1
ignition
systemusedon1996
and
later
6-cylinder
engines
.

1.0
BR

PQ

1
.08~1
.0BKIRD



/1
.0BK/YL



'10BK/BL



'1
.03KIGN



10BKNI
4
1D

BK
-
BLACK
BR
-
BROWN
RD
-
RED
YL
-
YELLOW
GN
-
GREEN
BL
-
BLUE
VI-
VIOLET
GY
-
GREY
WT
-
WHITE
PK
-
PINK

Batteryvoltage
in
run
or
start
(via
main
relay
terminal
87)

!1



rl
1.0
B~



^
1.0
BK/RD



^
1.0
BKIYL



^
1
.0
BK/BL



n
1.0
BK/GN



n
1
.0
BKIVI



%~
r
-------
--------------_____________----_______-_-____
49



29



1



30



2



31



3



8754
1
power
input



Power
input



I
1



Engine
Control
Module
(Siemens
MS
41
.1)



1
1



grounds



1
n
1



Powerinput
Mainrelaycontrol
1
1-
57

___
58



_
59
_
__
63
_



38



83



48



40



64



43



65



41



28



32



34



4



26



73



1
-



-----------
-
_-----
-
------
_
------
-
------
-
---



-

.5Y1-



.5BKY.5GNY.5BRY
Y



.35BKY
1
Y



Y



.35BKY/Y35YY
75
.18R/
.5YL-1
1'
.

Batteryvoltage
at
all
times
to
Main
relay
(terminal
85)

Ground



v
(RH
rear
of
engine



Z
compartment,
rear



=
of
shock
tower)



Ground
(RH
rear
of
enginecompartment,
rearof
shock
tower)



0012731

Alternator
brushes,



STARTER
SERVICE
inspecting
and
replacing

Regulator
brushesarenot
available
as
replacement
parts
from
BMW
.
Replacement
brushes
may
be
available
from
af-

termarket
sources,
however
.

1
.
Remove
voltage
regulator
as
described
above
.

2
.
Clean
brush
contact
sürfaces
and
measure
brush
pro-trusion
.
See
Fig
.
7
.

Check
for
battery
voltage
at
terminal
50
of
the
starter
motor
Fig
.
7
.



Regulator
brush
protrusion
(A)
.



with
the
key
in
the
start
position
.
See
Fig
.
8
.
If
voltage
is
not
present,
check
the
wiring
between
the
ignition
switch
and
the
starter
terminal
.
If
voltage
is
present
and
no
other
visible
wir
Voltage
Regulator



ing
faults
can
be
found,
the
problem
is
most
likely
interna¡in

"
Brush
protrusion
(minimum)
.......
.
..
5
mm
(
1
/4
in
.)



the
starter
motor
.

3
.
To
replace
brushes,
carefully
and
as
quickly
as
possi-

ble,
unsolder
brush
lead
from
brush
holder
termina¡,

withdrawing
brush
from
holder
at
same
time
.

4
.
Remove
any
traces
of
solder
frombrush
holder
termi-
nal
using
solder
wick
.

5
.
Fit
spring
into
brush
holder
and
inserí
new
brush
.

6
.
Guide
brush
lead
into
terminal
and
solder
into
place
.

Check
for
free
movement
of
brushes
when
solder

cools
.

7
.
Check
brush
slip
rings
in
alternator
for
wear
.
Lightly
clean
slip
rings
using
fine
abrasive
cloth
.

BATTERY,
STARTER,
ALTERNATOR



121-
7

Starter
Troubleshooting

If
the
starter
tucos
the
engine
slowlyor
fails
to
operate
when
the
ignition
isin
the
start
position,
check
the
battery
first
.
In-
spect
the
starter
wires,
terminals,
and
ground
connections
for
good
contact
.
In
particular,
make
sure
the
ground
connections
between
the
battery,
the
body
and
the
engine
are
completely
clean
and
tight
.
If
no
faults
can
be
found,
the
starter
may
be
faulty
and
should
be
replaced
.

NOTE
-

"
Starting
in1194,
a
factory-installed
drive-away
protec-
tion
system,
alsoreferred
to
as
EWS
or
EWS
11,
was
used
on
all
E36
cars
.
This
system
prevenís
operation
of
the
starter
when
the
system
is
engaged
.
See
515
Central
Locking
and
Anti-theft
.

"
On
cars
with
automatic
transmission,
a
starter
relay
and
a
neutral
safetyswitchare
used
to
present
theen-
ginefrom
starting
in
gear
positions
other
than
park
or
neutral
.
ff
voltage
is
not
present
atterminal
50
with
the
key
in
the
startposition,
check
these
components

To
make
the
most
accurate
check
of
the
battery
cables
and
starterwiring,
make
a
voltage
drop
test
on
the
cables
and
wir-

ing
as
described
in
600
Electrical
System-General
.

Terminal
30
'
\



/
Terminal
30h

0012518

8
.
Reinstall
regulator
and
alternator
.



Fig
.
8
.



Typical
starterwiring
terminal
identification
.
Large
wireat
ter-
minal
30
is
direct
battery
voltage
.
Smaller
wire
at
terminal
50
operates
starter
solenoid
via
ignition
switch
.

STARTER
SERVICE

GENERAL
.
.
.
.
.
.
.
.
.
...
.
.
.
.
.
.
.
.........
130-2



Intake
air
temperature
(IAT)
sensor,

Principles
of
Operatinn
.
.
.
.
.
.
.
.
.
.........
130-2



testing
and
replacing
...
.
...
.
.
.
.......
.
130-19

Basic
Engine
Settings
.
.
.
.
.
.
.
.
.
.
.
.
.
.
...
:
.
130-3



Throttle
position
sensor
(TPS),

DISA
(Dual
Resonance
Intake
System)
.
.
.
.
.
130-3



testing
and
replacing
...
.
...
.
.
.
.
.
...
.
.
.130-19

On-Board
Diagnostics
(OBD)



Idle
speed
control
valve,
testing
.
.
.
.
.
.
.
.
.
.
130-20

and
Fault
Diagnosis
.
.
....
.
......
.
.
.
...
130-4



Idle
speed
control
valve,
replacing
.
.
.
.
.
.
..
130-21

SecondaryAir
Injection
.
.
.....
.
.........
.
130-5



BOSCH
DME
M5
.2
COMPONENT
Warnings
and
Cautions
.
.
...
.
.
.
.........
.
130-6



REPLACEMENT
.....
.
......
.
....
.
.
.
..
130-21

ELECTRICAL
CHECKSAND



Mass
air
flow
sensor,
replacing
.
.
....
.
....
130-22

COMPONENT
TESTING
.
.
.
.
.
.
.
.
...
.
.
.
.
.
130-7



Engine
coolant
temperature
(ECT)

Main



sensor,
replacing
..
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
130-22
rela
y
testing



130
-7
,...
.
.
.
.
.
.
.
.
.
...
.
.
.
.
.
.
.



Intake
air
temperature
(IAT)
sensor,
Fuel
pump
relay,
testing
.
.
.
.
.
.
.
...
.
.
.
.
.
.
.
130-7



rep
lacin
.
.
.
.
.
.
.
.
.
.
.g



.
.
.
.
.
.
.
...
.
.
.
..
.130-22
Oxygen
sensor,
testing
(Boschsystems
only)
130-8



Throttle
poson
sensor
(TPS)
replacing



13022
,



..
.-

FUEL
DELIVERY
TESTS
...
.
....
.
.
.
...
.
130-9



Idle
speed
control
valve,
replacing
...
.
....
.130-23

Operating
fuel
pump
for
tests
.
.
.......
.
...
130-9



SIEMENS
MS
41
.1
COMPONENT
Relieving
fuel
pressure
and



REPLACEMENT
.
...
.
.
.
.
.
.......
.
....
.130-23
connecting
fuel
pressure
gauge
......
.
..
130-10

Residual
fuel
pressure,
testing
.
.....
.
.
.
.
.
130-10



Mass
air
flow
sensor,
replacing
.
.......
.
.
.130-25

Fuel
pressure
regulator
response



Engine
coolant
temperature
(ECT)

to
engine
load,
testing
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
130-11



sensor,
replacing
.....
.
.
.
.
.
.........
.130-25

Fuel
rail
and
injectors,
checking
...
.
.
.
.
.
.
.
130-11



Intake
air
temperature
(IAT)
sensor,
replacing
.
.
.
.
.
.....
.
.
.
.
.
.
.
.......
.
.
.130-25
Fuel
rail
and
injectors,
replacing



..
.
.
.
.
.
.
.
130-12



Throttleposition
sensor
(TPS),
replacing
.
.
.
130-26
Fuel
PressureRegulator
.........
.
.
.
.
.
.
.
130-13



Idle
s
eed
control
valve,
re
lacin



130-26
Fuel
pressure
regulatorreplacing



p



p



g
.'''...
.
'
,

(fuel
rail
mount)
...
.
.
.
.
.
.............
130-13



ECM
PIN
ASSIGNMENTS
.............
.
.
130-26
Fuel
pressure
regulator,
replacing



Engine
control
module
(ECM),
accessing
...
130-26
(undercar
mount)
.
.
.
.
.
.
.
.
.........
.
.
130-14

BOSCH
DME
M1
.7
COMPONENT

TESTS
AND
REPAIRS
.
.
.
.
.
...
.
.
.
.
.
.
.
.
130-14

Air
flow
sensor,
testing
and
replacing
.
.
.
.
.
.
130-14

Engine
coolant
temperature
(ECT)

sensor,
testing
and
replacing
...
.
.
.
.
.
.
.
.
130-15

Throttle
position
sensor
(TPS),

testing
and
replacing
.
..........
.
.....
130-16

Idle
speed
control
valve,
testing
and
replacing
.
.
.
.
.
............
130-16

BOSCH
DME
M3
.1
AND
M33
.1

COMPONENT
TESTS
AND
REPAIRS
.
.
.
130-17

Mass
Air
Flow
Sensor
.
.
.
.
.
.
.
.
.....
.
.
.
.
.130-17

Mass
air
flow
sensor
(hotwire),testing
and
replacing
.
.
.
.
.
.....
.
.
.
.
.
.
.
130-17

Mass
air
flow
sensor
(hot
film),

testíng
and
replacing
.
.
.
.....
.
.
.
.
.
.
.
.
.
130-18
Engine
coolant
temperature
(ECT)

sensor,
testing
and
replacing
..
.
.
.
.
.
...
.
130-18

130
Fuel
i
n
jection

FUEL
INJECTION



130-1

TABLES
a
.
Engine
Management
System
Variants
.........
.130-2
b
.
Mass
Air
Flow
Sensor
Variants
..
.
..
..........
.130-2
c
.
Fuel
Pressure
Specifications
..
.
.
...
..........
130-11
d
.
Engine
Coolant
Temperature
Sensor
or
Intake
Air
Temperature
Sensor
Test
Values
(DME
1
.7)
...
.
130-15
e
.
ThrottlePosition
Sensor
Tests
(DME
1
.7)
......
.130-16
f
.



Engine
Coolant
Temperature
Sensor
or
Intake
Air

Temperature
Sensor
Test
Values
(DME
3
.1/3
.3
.1)130-19
g
.
Throttle
Position
Sensor
Tests
(DME
3
.1/3.3
.1)
.
.130-20
h
.
ECM
Pin
Assignment-Bosch
DME
M1
.7
....
.
..
.130-28
i.



ECM
Pin
Assignment-Bosch
DME
M3
.1
.......
.130-30
j
.



ECM
Pin
Assignment-Bosch
DME
M3
.3
.1
.....
.130-32
k
.
ECM
Pin
Assignment-Bosch
DME
M5
.2
.......
.
130-34
I.



ECM
Pin
Assignment-Siemens
DME
MS
41
.1
..
.
130-36

130-
4



FUEL
INJECTION

Main
Relay

Fig
.
2
.



DISA
system
components
.
DISA
is
controlled
via
theengine
control
module
(ECM)
.

Fig
.
3
.



DISA
manifold
runners
with
butterfly
valve
closed
for
lowrpm-
high
torque
operation
.

yje
q

GENERAL

high
power
operation
.

0012734

Fig
.
4
.



DISA
manifold
runners
with
butterfly
valve
open
for
high
rpm-

On-Board
Diagnostics
(OBD)

and
Fault
Diagnosis

Poor
driveability
may
have
a
variety
of
causes
.
The
fault

may
He
withthe
ignition
system,
the
fuel
system,
parts
ofthe

emission
control
system,
ora
combination
of
thethree
.
Be-

cause
of
these
interrelated
functions
and
their
effects
on
each
other,
it
is
often
difficult
to
know
where
to
begin
looking
for

problems
.

For
this
reason,
effective
troubleshooting
should
always
be-

gin
with
an
interrogation
of
the
On-Board
Diagnostic
(01313)

system
.

The
OBD
system
detects
certain
emissions-related
engine

management
malfunctions
.
When
faults
are
detected,the

OBD
system
storesa
Diagnostic
Trouble
Code
(DTC)
in
the

system
ECM
.
In
addition,
the
Check
Engine
warning
light
will

come
on
if
an
emissions-related
fault
is
detected
.

Two
generations
of
OBD
are
used
on
thecars
covered
by
this
manual
.
See
100
Engine-General
for
OBD
I
information

and
fault
codes
.

On-Board
Diagnostics

"
1992-1995models
....
.
...
...
.
...
......
OBD
I

"
1996-1998models
....
.
..
.
.
.
..
...
......
OBD
II

130-
6



FUEL
INJECTION

Warnings
and
Cautions

For
personal
safety,
as
well
as
the
protection
of
sensitive

electronic
components,
the
following
warnings
and
cautions

should
be
adhered
to
when
working
on
the
engine
manage-

ment
system
.

GENERAL
WARNING
-

"
The
ignition
system
produces
high
voltages
that

can
be
fatal
.
Avoid
contact
with
exposed
termi-

nals
.
Use
extreme
caution
when
working
onacar
with
the
ignition
switched
on
or
the
engine
run-
ning
.

"
Do
not
touch
or
disconnect
any
high
voltage
ca-

bles
from
the
coils
or
spark
plugs
while
the
engine

is
running
or
beingcranked
by
the
starter
.

"
Connect
and
disconnect
the
DME
system
wiring
and
test
equipment
leads
only
when
the
ignition
is
switched
off
.

"
Gasoline
is
highly
flammable
and
fts
vaporsare

explosive
.
Do
not
smoke
or
work
on
a
car
near
heaters
or
other
fire
hazards
when
diagnosing
and
repalring
fuel
system
problems
.
Have
a
tire
extinguisher
avaílable
in
case
of
an
emergency
.

"
When
working
onan
open
fuel
system,
wear
suit-
able
hand
protection,
asprolonged
contact
wfth
fuel
can
cause
illnesses
and
skin
disorders
.

"
Renew
fuel
system
hoses,
clamps
and
O-rings
any
timethey
are
removed
.

"
Before
makingany
electrical
tests
that
require
the
engine
to
be
cranked
using
the
starter,
disable
the
ignition
system
as
described
in
120
Ignition
System
.

CAUTION-

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

"
Do
not
connect
any
test
equipment
that
delivers

a
12-volt
power
supply
to
terminal
15
(+)
of
the
ig-

nitioncoil
.
The
current
flow
may
damage
the

ECM
.
In
general,
connect
test
equipment
only
as

speclfied
by
BMW,
this
manual,
or
the
equipment

maker
.

"
Only
use
a
digital
multlmeter
for
electrical
test
.

"
Only
use
an
LED
test
light
for
quick
tests
.

"
Disconnecting
the
battery
may
erase
fault

code(s)
stored
in
memory
.
Check
for
fault
codes

prior
to
disconnecting
the
battery
cables
.
ff
the

Check
Engine
light
ís
illuminated,
see100En-
gine-General
for
DME
fault
code
information
.
ff
any
other
system
faults
have
been
detected
(indi-
catedbyan
illuminated
warning
light),
see
an
au-
thorized
BMW
dealer
.
Additional
systems
with
self-diagnostic
capabilities
include,
ABS
(Anti-
lock
brakes),
SRS
(Airbags),
EML
and
ASC+T
and
AST
(Traction
Control)
.

"
Do
not
run
the
engine
wfth
any
of
the
spark
plug
wires
dlsconnected
.
Catalytic
converter
damage
may
result
.

"
Always
waitat
least
40
seconds
afterturning
off
the
ignition
before
removing
the
engine
control
module
(ECM)
connector
.
ff
the
connector
isre-
moved
before
this
time,
residual
power
in
the
sys-
tem
relay
may
damage
the
control
module
.

"
Cleanliness
is
essential
when
working
onan
open
fuel
system
.
Thoroughly
clean
fuel
line
con-
nections
and
surroundlng
areas
before
loosen-
ing
.
Avoid
moving
the
car
.
Only
fnstall
cleanparts
.

"
Fuel
system
cleaners
and
other
chemical
addi-
tives
other
than
those
specifically
recommended
by
BMW
may
damage
the
catalytic
converter,
the
oxygensensor
or
other
fuel
supply
components
.

ELECTRICAL
CHECKS
AND
COMPONENT
TESTING

Main
relay,
testing

The
main
relay
is
energized
via
the
engine
control
module

and
supplies
plus
(+)
power
to
the
many
of
the
engine
man-

agement
components
and
subsystems,
including
the
fuel

pump
relay
.
If
this
relay
is
faulty,
the
engine
will
not
start
.

1
.
With
ignition
off,
remove
main
relay
.
See
Fig
.
6
.

.

iommooommmoi



~
"""

Fuel
DME
sensor

CA
UTION-

Relay
positions
can
vary
.
Be
sure
to
confirm
relay
position
by
identífyíng
the
wiring
in
the
socket
us-
ingthe
wiring
diagramsfound
at
the
rearof
this

manual
.

0013034)
Fuel
pump
relay,
testing

FUEL
INJECTION



130-
7

87

851186

30
~j

1
.
Remove
fuel
pump
relay
from
its
socket
.

87661

Fig
.
7
.



Check
for
battery
voltage
at
main
relay
terminals
30
and
86
.
Voltage
should
be
present
at
all
times
.

4
.
With
ignition
on
and
relay
installed,
check
for
battery

voltage
at
terminals
87
.

"
If
battery
voltage
is
present,relay
has
energized
and
is

functioningcorrectly
.

"
lf
battery
voltage
is
not
present
and
al¡
earlier
tests
are

OK,
relay
is
faulty
and
should
be
replaced
.

Fig
.
6
.



Engine
management
relays
in
the
power
distribution
box,
left
rear
of
engine
compartment
.



The
fuel
pump
relay
is
located
in
the
power
distribution
box
.

Refer
to
Fig
.
6
.

The
ECM
supplies
power
to
the
coil
side
of
the
fuel
pump
re-

lay
.
During
starting,
the
fuel
pump
runs
as
long
as
the
ignition

switch
isin
the
start
position
and
continues
to
run
once
theen-

gine
starts
.
If
the
relay
ís
faulty
the
fuel
pump
will
notrun
.

2
.
Check
for
voltage
at
terminal
30
and
terminal
86
of
re-

¡ay
socket
.
See
Fig
.
7
.



2
.
With
key
off,
check
for
batteryvoltage
at
socket
terminal

"
If
battery
voltage
is
present
continue
testing



30
.
See
Fig
.
8
.

"
lf
battery
voltage
is
not
present
at
either
point,
check

large
red
wire
in
relay
socket
.
See
Electrical
Wiring



3
.
With
ignition
key
in
start
position
check
for
battery
volt-

Diagrams
.



age
at
terminal
86
.

NOTE-



4
.
With
ignition
key,
use
digital
multimeter
to
check
for

The
wiring
to
terminals
85
and
86
in
the
main
relay
may



ground
at
terminal
85
.

be
reversed
.
Electrically,
the
relay
functions
either
way
.

lf
voltage
ís
not
present
at
terminal
86,
check
for
volt-



NOTE-
age
at
terminal
85
.



The
ground
atterminal
85
is
switched
by
the
ECM
.
The

ECM
hamess
must
be
connected
to
check
the

3
.
Reinstall
relay
and
turn
ignition
on
.
Gainaccess
to
un-



switched
ground
connection
.

derside
of
relay
socket
and
check
for
ground
at
terminal

85
(brown
wire)
.



5
.
If
no
faults
are
found
up
tothis
point,
testfuel
pump
op-

"
lf
ground
is
present
continue
testing
.



eration
as
described
in
160
Fuel
Tank
and
Fuel
Pump
.

"
If
ground
is
not
present,
signal
from
ECM
is
missing
.

Check
wire
between
ECM
and
relay
.
If
no
faults
can

be
found,
ECM
may
be
faulty
.

ELECTRICAL
CHECKS
AND
COMPONENT
TESTING