1997 BMW 328i dme relay

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

130-
1
4



FUEL
INJECTION

NOTE-

Be
sure
to
retrieve
thrust
washer
behind
fuel
pressure
regulator
on
6-cylinder
engine
.

4
.
Installation
is
reverse
of
removal
.
Replace
O-rings
.

Fuel
pressure
regulator,
replacing

(under
car
mount)

WARNING
-

Fuel
will
be
discharged
.
Do
not
disconnect
any
wires
that
could
cause
electrical
sparks
.
Do
not
smoke
or
work
near
heaters
or
other
fire
hazards
.
Keep
an
approved
tire
extinguisher
handy
.

On
late
4-
and
6-cylinder
cars,
the
fuel
pressure
regulator
is

mounted
beneath
the
left
sideof
the
car,
under
a
protective

cover
.
See
Fig
.
20
.

0012726

Fig
.
20
.
Fuel
pressure
regulatorlocation
underneath
car
(arrow)
.
Vac-
uum
hose
to
regulator
is
shown
at
A
.
(Protective
cover
has
been
removed
.)

5
.
Installation
is
reverse
of
removal
.
Replace
O-rings
.

BOSCH
DME
Ml
.
7
COMPONENT
TESTS
AND
REPAIRS

BOSCH
DME
Ml
.7
COMPONENT

TESTS
AND
REPAIRS

CA
UTION-

Use
only
a
digital
multimeter
when
testing
compo-
nents
and
wiring
.
Use
of
an
analog
VOM
may
damage
the
engine
control
module
.

4-cylinder
cars
with
M42
engines(1992
to
1995)use
the

Bosch
DME
M1
.7
fuel
injection
system
.

Electrical
tests
of
the
main
and
fuel
pump
relays
and
the

DME
engine
control
module
(ECM)
are
covered
earlier
in
this

section
.
Fuel
pump
tests
arecovered
in
160
Fuel
Tank
and

Fuel
Pump
.

Air
flow
sensor,
testing
and
replacing

DME
M1
.7
fuel
injection
uses
a
volume
air
flow
type
sensor

with
integrated
intake
air
temperature
(IAT)
sensor
.
The
sen-

sor
provides
a
varyingvoltage
signal
to
the
ECM
based
on
the

position
of
the
air
vane
.
As
the
vane
doorswings
open
thepo-
tentiometer
increases
the
voltage
signal
to
the
ECM
.
The
IATsensor
adapts
theoutput
signal
to
the
ECM
based
on
intake

air
temperature
.

1
.
Check
ECM
reference
voltage
to
sensor
:

"
Peel
back
rubber
boot
from
air
flow
sensor
harness

connector
.

"
Turn
ignition
keyon
.
"
Check
for
5
volts
between
terminal
1
of
harness
con-
nector
and
ground
.
See
Fig
.
21
.

"
Turn
ignition
key
off
.

"
If
voltage
is
not
present
or
incorrect,
check
wring
from

ECM
and
check
air
flow
sensor
reference
voltage
out-

put
at
ECM
.
See
Table
h
.
1
.
Working
under
car
below
driver's
seat,
remove
protec-
tive
cover
from
below
fuel
pressure
regulator
.

"
Remove
intake
air
bootfrom
sensor
.
2
.
Remove
vacuum
hosefrom
fuel
pressure
regulator
.



"
Connect
a
digital
multimeter
(ohms)
across
terminais
1

and
2
.
Swing
air
flow
sensor
vane
through
its
travel
3
.
Remove
locking
clip
retaining
fuel
pressure
regulator
.



range
.
Resistance
should
change
steadily
without
in-

terruption
.
4
.
Wrap
a
shop
rag
around
regulator,
then
remove
regula-



"
If
any
faults
are
found,
the
air
flow
sensor
is
faulty
and
tor
from
213
way
valve
by
pullingstraight
out
.



should
be
replaced
.

2
.
Check
air
flow
sensor
potentiometer
:

3
.
Check
IAT
sensor
resistance
:

"
With
harness
connector
disconnected
at
air
flow
sen-
sor,
check
resistance
across
sensor
terminais
4
and
5

of
air
flow
sensor
.
Compare
tests
results
to
values
in
Table
d
given
later
.
If
any
faults
are
found,
the
air
flow
sensor
should
be
replaced
.

130-
1
6



FUEL
INJECTION

Throttie
position
sensor
(TPS),



Idie
speed
control
valve,
testing
and
replacing



testing
and
replacing

The
throttie
position
sensor
(TPS)
is
mounted
on
the
side
of



¡die
speed
is
maintained
by
the
ECM
via
the
¡die
speed
con-

the
throttie
housing
and
is
directly
connected
to
the
throttie



trol
valve
.
See
Fig
.
24
.
¡die
speed
is
adaptive
through
the
valve
shaft
.
The
ECM
sends
a
voltage
signal
to
the
potentiom-



ECM
and
no
¡die
speed
adjustments
can
be
made
.
Before
eter-type
sensor
and
monitors
the
voltage
that
comes
back
.



testing
the
valve,
confirm
that
the
throttie
position
sensor(TPS)
is
working
correctly
.

Check
TPS
function
by
disconnecting
the
harnessconnec-

tor
and
checking
reference
voltage
and
sensor
resistance
.

See
Table
e
and
Fig
.
23
.
If
voltage
is
not
present,
check
the

output
voltage
signal
from
the
ECM
and
check
the
wiring
be-
tween
the
sensor
and
the
ECM
.
If
the
sensor
resistance
is
in-
correct,
replace
the
throttie
position
sensor
.

NOTE
-

The
throttie
position
sensor
is
not
adjustable
.
If
test
re-
sults
are
íncorrect,
the
sensor
should
be
replaced
.

Table
e
.
Throttle
Position
Sensor
Tests

(DME
1
.7)

Testconditions



1
Terminais



1
Test
value

Harness
connec-



(
1
and
ground
in



15
VDC
(approx
.)
tor
disconnected,



harness
connector
ignition
on

0013235

Fig
.
23
.
Throttieposition
sensor
terminal
identification
on
M42
engine
.

Harnessconnec-



I
1
and
3
at
sensor



(
4k
ohms
(approx
.)
tor
disconnected,



terminais
ignition
off
Connector
dis-



1
and
2
at
sensor



Continuously
vari-
connected,
igni-



terminais



able
from
1-4
k
tion
off
.
Throttle



ohms
(approx
.)
with
rotated
from
¡die



out
interruption
to
fui]
position

BOSCH
DME
Ml
.
7
COMPONENT
TESTS
AND
REPAIRS

Fig
.
24
.
¡die
speed
control
valve
(arrow)
on
M42
engine
.

NOTE
-

"
The
tests
given
below
are
electrical
checks
only
.
They
do
not
check
the
mechanical
operation
of
the
valve
or
if
the
valve
is
sticking
or
worn
.
If
the
valve
is
suspect,
substituting
a
known
good
valve
is
the
best
way
to
check
for
amechanical
fault
.

1
.
Check
battery
(+)
voltage
to
valve
:

0013226

"
Disconnect
harness
connector
from
valve
.
"
Check
for
battery
voltage
at
terminal
2
(red/white
wire)
.
"
If
voltage
is
not
present
check
wiring
between
valve
and
main
relay
(terminal
87)
.

2
.
Check
that
ECM
signal
is
reaching
valve
:

"
With
engine
running,
check
that
¡die
speed
control
valve
is
audibly
buzzing
.
"
If
valve
is
not
working,
disconnect
wiring
harness
con-
nector
.

"
Connect
12V
probe
light
across
connector
terminais
.
"
Turn
ignition
key
on
;
probe
should
light
.
lf
probe
does
nof
light,
check
the
wiring
from
the
ECM
(pin
29)
to
the
valve
.
See
Table
h
.
lf
probe
does
light
but
¡die
quality
is
poor,
the
valve
is
most
likely
sticking
and
or
worn
and
should
be
replaced
.

BOSCH
DME
MM
AND
M33
.1

COMPONENT
TESTS
AND
REPAIRS

Consult
Table
a
for
engine
application
information
for
the

Bosch
DME
3
.1
and
3
.3.1
systems
.

The
DME
3
.1
and
DME
3
.3
.1
systems
are
similar
in
opera-

tion,
with
knock
control
and
VANOS
operation
being
the
key

differences
.
DME
3
.1
engines
arenot
equipped
with
VANOS

or
knock
detectors,
while
the
DM
E3
.3
.1
system
is
.

CA
UTION-

Use
onty
a
digital
multimeter
when
testing
wiring
.
Use
of
an
analog
VOM
may
damage
the
engine
control
module
.

Fig
.
25
.
Mass
air
flow
sensor
.
Hot
wire
sensor
usedon
carswith
DME
Electrical
tests
of
the
main
and
fuel
pump
relays
and
the



3
.1
(1992
6-cylinder
models)
.

DME
engine
control
module
(ECM)
are
covered
earlier
in
this

section
.
Fuel
pump
tests
are
covered
in
160
Fuel
Tank
and



CAUTION-
Fuel
Pump
.
Use
only
a
digital
multimeter
when
checking
the
mass
air
flow
sensor
.
An
analog
meter
can
dam-
Mass
Air
Flow
Sensor



age
theair
flow
sensor
.

There
are
two
types
of
mass
air
flow
sensors
used
onthe



1
.
Disconnect
air
flow
sensor
from
air
cleaner
only
.
Leave

cars
covered
by
this
section
.
Testing
procedures
vary
de-



it
connected
to
duct
leading
to
intake
manifold
and

pending
on
type
installed
.
The
airflow
sensor
is
not
adjustable



leave
wiring
harness
connected
.

and
must
only
be
tested
with
a
digital
multimeter
.

Mass
Air
FlowSensor
Variants

"
1992
M50
engine

DME
M3
.1
.
.
.
.
...
..
mass
air
flow
sensor-hot
wire

"
1993-1995
M50
and
S50US

DMEM33
.1)
.
...
...
.
mass
air
flow
sensor-hot
film

Mass
air
flow
sensor
(hot
wire),

testing
and
replacing

When
the
engine
is
running,
a
current
is
used
to
heat
a
thin

wire
in
the
center
of
the
sensor
.
See
Fig
.
25
.
The
current
in
the

wire
is
regulated
to
maintain
a
temperature
of
100°C
more

than
the
air
passing
over
it
.
The
current
used
to
heat
the
wire

is
electronically
conneced
into
a
voltage
measurement
corre-

sponding
to
the
mass
of
intake
a¡
r
.

To
keep
the
wire
clean,
it
is
heated
to
a
temperature
of
about

1,000°C
(1,830°F)
for
one
second
.
This
"burn-off"
cycle
takes

place
automatically,
four
seconds
after
the
engine
is
tumed
off
.

lf
thehot
wire
breaks
or
if
there
is
no
output
from
the
air
flow

sensor,
the
ECM
automatically
switches
to
a
"limp-home"

mode
and
tucos
on
the
Check
Engine
light
.
The
engine
can

usually
be
started
and
driven
.
The
air
flow
sensor
has
no
inter-

nal
moving
parts
and
cannot
be
serviced
.

FUEL
INJECTION



130-
1
7

2
.
Start
engine
and
run
it
to
normal
operating
temperature
.

3
.
Rev
engine
toat
least
2,500
rpm,then
shut
it
off
.
Look

through
meter
at
hot
wire
.
After
approximately
four
sec-

onds
wire
should
glow
brightly
for
about
one
second
.

NOTE
-

If
the
wire
glowsas
specified,
then
the
airflow
meter
and
ECM
are
probably
operating
correctly
.
lf
the
wire
does
not
glow,
continue
testing
.

4
.
lf
the
wire
does
not
glow,
remove
air
flow
sensor
and

look
through
it
to
see
if
wire
is
broken
.
lf
wire
is
broken,

meter
will
have
to
be
replaced
.

5
.
Reinstall
air
flow
sensor
and
harness
connector
.
Peel

back
rubber
bootfrom
harness
connector
.
Working

from
rear
of
connector,
connect
digital
voltmeter
across

terminals
1
and
4
.
See
Fig
.
26
.

6
.
Start
and
rev
engine
toat
least
2,500
rpm,thenshut
it

off
.
After
about
4
seconds,
voltage
should
riseto
about

4
volts
for
about
one
second
.
lf
voltage
is
present,
but

wire
does
not
glow,
air
flow
sensor
is
faulty
and
should

be
replaced
.

7
.
lf
voltage
is
not
present
in
step
6,
turn
ignition
key
on

and
check
for
voltage
and
ground
at
sensor
.
There

should
beground
at
pin
4
.
There
should
be
positive
(+)

battery
voltage
at
pin
2
.

BOSCH
DME
M3
.1
AND
M32
.1
COMPONENT
TESTS
AND
REPAIRS

130-18



FUEL
INJECTION
The
engine
coolant
temperature
(ECT)
sensor
sends
con-

tinuous
engine
coolant
temperature
information
to
the
ECM
.
Fig
.
26
.
Mass
air
flow
sensor
terminalidentifcation
on
carswith
DME



As
temperature
increases
sensor
resistance
decreases
.
M3
.1
fuel
injection
.

Mass
air
flow
sensor
(hot
film),

testing
and
replacing

MOTE-

A
burn-off
cycle
is
not
used
on
hot
film
sensors
.

8
.
With
ignition
off,
disconnect
harness
connector
from
air



ECT
Sensor
Location
flow
sensor
.
Using
a
digital
multimeter,
check
resis-



"
M50/S50US
engine
............
left
side
of
cylinder
tance
at
terminals
listed
.



head
under
intake
manifold

Air
Flow
Sensor
Test
Values
(DMEM3
.1)

"
Terminals
5
and
6
.
.
.
.........
..
.
..
....
3-4
ohms

If
any
faults
are
found,
check
wiring
lo
and
from
the
ECM
.
Make
ECM
pinout
test
as
listed
in
See
Table
i
.
Main
power
to
air
flow
sensor
comes
from
DME
main
relay
.

On
cars
with
DME
M3
.3
.1
a
hot
film
mass
air
flow
sensor
is
used
.
When
the
engine
is
running,
a
current
is
used
lo
heat
a
thinfilm
in
the
center
of
the
sensor
.
This
current
is
electroni-
cally
converted
into
a
voltage
measurement
corresponding
to
the
mass
of
intake
air
.

If
thehot
film
breaks
or
if
there
is
no
output
from
the
air
flow
sensor,
the
ECM
automatically
switches
to
a
"limp-home"
mode
and
tucos
on
the
Check
Engine
light
.
The
engine
can
usually
be
started
and
driven
.
The
air
flow
sensor
has
no
inter-
nal
moving
parts
and
cannot
be
senricedor
adjusted
.

CA
UTION-

Use
only
a
digital
multimeter
when
checking
the
mass
air
flow
sensor
.
An
analogmetercan
dam-
age
the
air
flow
sensor
.

BOSCH
DME
M3
.
1
AND
M32
.1
COMPONENT
TESTS
AND
REPAIRS

1
.
Disconnect
harnessconnector
from
air
flow
sensor
.

2
.
Turn
ignition
on
and
check
for
voltage
and
ground
at

connector
.
There
should
beground
at
pin
1
.
There

should
be
positive
(+)
battery
voltage
at
pin
3
.
If
any
faults
are
found,
check
wiring
to
and
from
ECM
.
Make
ECM
pinout
test
.
See
Table
j
.

NOTE-

Positive
(+)
battery
voltage
to
air
flow
sensor
comes
from
DME
main
relay
when
the
ignition
is
switch
on
orengine
running
.

Engine
coolant
temperature
(ECT)
sensor,

testing
and
replacing

0012704
Fig
.
27
.
Engine
coolant
temperature
(ECT)
sensor
(A)
is
located
be-
neath
top
engine
cover
(B)
and
crankcase
vent
hose
(C)
.
M52
engine
shown
.
M50
is
similar
.

1
.
Check
ECM
reference
voltage
to
sensor
:
"
Disconnect
harnessconnector
from
ECT
sensor
.
"
Turn
ignition
keyon
.
"
Check
for
5
volts
between
supply
voltage
wire
(brown/red)
wire
of
harness
connector
and
ground
.
"
Turn
ignition
key
off
.
"
If
voltage
is'
not
present
or
incorrect,
check
wiring
from
ECM
and
check
referencevoltage
output
at
ECM
(pin
78)
.
See
Table
i
(DM
E
3
.1)
or
Table
j
(DME
3
.3
.1)

2
.
Check
ECT
sensor
resistance
:

"
With
harnessconnector
disconnected,
check
resis-
tance
acrosssensor
terminals
.
"
Compare
tests
results
to
values
in
Table
f
.

130-20



FUEL
INJECTION

Fig
.
29
.
Throttleposition
sensor
terminal
identification
on
M50
engine
.

Tableg
.
Throttle
Position
Sensor
Tests

(DME3
.113
.3
.1)

Test
conditions



I
Terminals



I
Testvalue

Harness
connector



13
andground



15
VDC
(approx
.)
disconnected,
igni-



in
harness
tion
on



connector

Harness
connector



1
and3
at
sen-
14
k
ohms
(approx
.)
disconnected,
igni-



sor
terminals
tion
off

Throttle
plate
rotat-



1
and
2
at
sen-



Variable
from
1
-
4ked
from
¡dieto
full



sor
terminals



ohms
(approx
.)
with-
throttle
position



out
interruption



¡die
Speed
Control
Valve
Coil
Resistance
Values

"
M50/S50US
engine

NOTE-



Terminals
1
and
2
..
.
................
20
t
5
ohms

On
cars
with
tractioncontrol,
do
not
confuse
the
throttle



Terminals
2
and
3
...................
20
t5
ohms
position
sensor
on
the
main
throttle
body
with
the
throt-



Terminals
1
and
3
..
.
..
:
............
.40
t
5
ohms
tle
positionswitch
on
the
secondary
throttle
body,
where
applicable
.

¡die
speed
control
valve,
testing

¡die
speed
is
maintained
by
the
ECM
through
the
¡die
speed
control
valve
.
The
¡die
controlfunction
compensates
for
engine
load
and
engine
operating
conditions
.
¡die
speed
is
adaptive
through
the
ECM
and
no
¡die
speed
adjustments
can
be
made
.

NOTE-
Before
testing
the
valve,
confirm
that
the
throttle
position



The
idle
speed
controlvalve
receives
positive
(+)
bat-
sensor
is
working
correctly
.



tery
voltage
from
the
main
relay
.

BOSCH
DME
M3
.
1
AND
M3
.3
.1
COMPONENT
TESTS
AND
REPAIRS

NOTE-

"
The
tests
given
below
are
electrical
checks
only
.
They

do
not
check
the
mechanical
operation
of
the
valve
.
If
the
valve
is
suspected
of
causing
poor
idie,
substitut-
ing
a
known
good
valve
is
the
best
way
to
check
for
a
mechanical
fault
.

1
.
With
engine
running,
check
that
¡die
speed
control

valve
is
buzzing
.

2
.
Turn
on
A/C
or
shift
car
finto
drive
.
¡die
should
remain
steady
orincrease
slightly
.

3
.
If
valve
is
not
buzzing,or
if
¡die
decreases
in
step
2,

stop
engine
and
disconnect
harness
connector
from
valve
.
Check
resistance
of
valve
across
its
terminals
.

See
Fig
.
30
.
Test
values
are
listed
below
.

NOTE
-

If
you
suspect
an
intermittent
fault,
lightly
tapthe
valve
while
testing
resistance
.

11250

Fig
.
30
.
¡die
speed
control
valve
terminal
identification
.

4
.
With
valve
harnessconnector
disconnected,
check
for
battery
voltage
at
red/white
wire
in
connector
with
igni-

tion
tumed
on
.

"
If
there
is
no
voltage,
check
wiring
between
connec-
tor
and
main
relayterminal
87
.
See
Electrical
Wiring
Diagrams
.

5
.
If
voltage
is
presentas
described
above,
check
wiring
between
ECM
and
valve
.
If
no
wiring
faults
are
found,
check
ECM
signal
to
valve
.

130-
2
8



FUEL
INJECTION

Tableh
.
ECM
Pin
Assignment-Bosch
DME
M1
.7

Pin
Signal
Componenttfunction



Signal

1



Output



Fuel
pump
relay
control



Fuel
pump
relay,
terminal
85

2



Not
used

3



Output



Cyl
.
2
and
cyl
.
4
fuel
injection
valve
control



Cyl
.
2
and
cyl
.
4
fuel
injection
valves
4



Not
used

5



Not
used

6



Ground



Ground,
fuel
injection
valveoutputstages



Ground
point

7



Not
used

8



Output



"Check
engine"
indicator
control



Instrument
cluster

9



Not
used

10



Not
used

11



Output



DKV
potentiometer
signal



Transmission
control
module
(EGS)

12



Input



Throttleposition
sensor



Throttleposition
Signal

13



Not
used

14



Input



Volume
air
flow
sensor



Volume
air
flow
sensor
(signal
ground)

15



Input



Cyl
.
1-2
knock
sensor



Cyl
.
1-2
knock
sensor

16



Input



Camshaft
position
sensor
(cylinder
identification)



Camshaft
position
sensor
(cylinder
identification)

17



Output



ti
measurement
signal
(fuel
consumption)



Instrument
cluster

18



Output



Intakeair
resonance
changeover
valve
(DISA)



Intake
air
resonance
changeover
valve
19



-



Not
used

20



Not
used

21



Not
used

22



Not
used

23



Not
used

24



Output



Cyl
.
3
ignition
coil
control



Cyl
.
3
ignition
coil

25



Output



Cyl
.
1
ignition
coil
control



Cyl
.
1
ignition
coil

26



Input



Battery
voltage



B
+junction
point

27



Output



Engine
control
module
relay
control



Engine
control
module
relay,
terminal
85
28



Ground



Ground
for
electronics
and
shielding
of
sensors



Ground
point

29



Output



Idle
speed
control
valve
control



Idle
speed
control
valve

30



Not
used

31



Not
used

32



Output



Cyl
.
1
and
cyl
.
3
fuel
injection
valve
control



Cyl
.
1
and
cyl
.
3
fuel
injection
valves

33



Not
used
34



Ground



Ground,
output
stages
(except
for
ignition
and
fuel



Ground
point
injection
valves)

35



Not
used

36



Output



Evaporative
emissionvalve
control



Evaporative
emission
valve

37



Output



Oxygen
sensor
heater
control



Oxygen
sensor
relay,
terminal
85
38



Not
used
39



Not
used
40



I
Not
used

41



I
Input



,
Volume
Air
Flow
sensor



Volume
air
flow
sensor
(voltage
varies
with
engine
load)

42



1
Input



1
Cyl
.
3-4
knock
sensor



1
Cyl
.
3-4
knock
sensor

43



Ground



Ground
for
sensors



Engine
coolant
temperature
sensor,
cyl
.
1-2
knock
sensor,
cyl
.
3-4
knock
sensor,
and
throttle
position
sensor

44



1
Input



1
Camshaft
position
sensor
(cylinder
identification)



1
Camshaft
position
sensor
(cylinder
identification)

ECM
PIN
ASSIGNMENTS