1993 BMW M3 oil

120-
6



IGNITION
SYSTEM

Crankshaft
position/rpm
sensor,

testing
and
replacing
(front
mounted)

1
.
Disconnect
sensor
harness
connector
.

2
.
Using
a
digital
multimeter,
check
resistance
between
terminals
1
and
2
in
connector
.
See
Fig
.
10
.

n1
n2n3

Fig
.
10
.
Crankshaft
position/rpm
sensorconnector
.

Crankshaft
positionlrpm
sensor
specifications

"
Coil
resistance
(approx
.)
terminais
1
and
2
....
.
..
...
....
1280
±
10%
ohms

"
Air
gap
(sensor
distance
from
toothed
wheel)
..
.
.
........
.1
.0
±
0
.3
mm
(0
.04
±
0
.01
in
.)

3
.
If
the
resistance
is
not
correct,
the
sensor
is
faulty
and
should
be
replaced
.

NOTE
-

When
installing
the
new
sensor,
be
sure
thewiring
Is
rerouted
in
the
same
orientation
.
Secure
the
sensor
us-
ing
new
wire
ties
.

Tightening
Torque

"
Crankshaft
position/rpm
sensor
to
mounting
bracket
.........
.
.
5
t
1
Nm
(62
t
9
in-lb)

Crankshaft
position/rpm
sensor,



4
.
Installation
is
reverse
of
removal
.
Use
a
new
O-ring
replacing
(rear
mounted)



when
installing
sensor
.
Be
sure
wiring
is
rerouted
in
same
orientation
.
1
.
Disconnect
sensor
harness
connector
.

6502AGN56

2
.
Locatesensor
on
rear
left
sideof
cylinder
block
.
Re-
move
sensormounting
bolt
and
remove
sensorfrom
cylinder
block
.

IGNITION
SYSTEM
SERVICE

3
.
Installation
is
reverse
of
removal
.
Use
a
new
O-ring

when
installing
sensor
.
Be
sure
wiring
is
rerouted
in
same
orientation
.
Secure
sensor
using
new
wire
ties
.

NOTE-

It
may
be
easier
to
remove
the
sensor
working
from
the
underside
of
the
vehicle
.

Camshaft
Position
(CMP)
Sensor

The
camshaft
position
(CMP)
sensor
is
usedby
the
engine
management
system
for
sequential
fuel
injection
and
knock
control
.

Camshaft
position
(CMP)
sensor,

replacing
(4-cylinder
engine)

1
.
Remove
CMP
sensorfromtop
timing
cover,
just
above
coolantthermostat
housing
.
See
Fig
.
11
.

Fig
.
11
.
Camshaft
position
sensor
mounting
bolt
(arrow)
.
M42
engine
shown
.

2
.
On
M42
engines
to
9/93
:
Disconnect
CMP
harness
plug
just
above
oil
filter
housing
.

3
.
On
M42
from9/93
and
all
M44
engines
:
Remove
upper
intake
manifold
as
described
in
113
Cylinder
Head
Re-
moval
and
Installation
.
Then
unplug
CMP
sensor
har-
ness
connector
below
manifold
.

Camshaft
position
(CMP)
sensor,

replacing
(6-cylinder
engine)

1
.
Remove
plastic
cover
from
above
fuel
injectors
.

2
.
Disconnect
harness
connector
from
VANOS
solenoid

and
unscrew
solenoid
from
VANOS
control
unit
.
Re-



"
Clean
contactsurface
on
engine
block
before
fnstall

move
oil
supply
line
from
VANOS
control
unit
.
See
117



ing
knock
sensors
.

Camshaft
Timing
Chain
.

3
.
Remove
camshaft
position
(CMP)
sensor
from
left
frontof

cylinder
head,
next
to
top
of
oil
filter
housing
.



"
Knock
sensor
to
cylinder
block
....
20
Nm
(15
ft
.
lbs
.)

4
.
Disconnect
CMP
sensor
harnessfrom
under
intake

manifold
.

5
.
Installation
is
reverse
of
removal
.
Use
a
new
O-ring

when
installing
sensor
.
Be
sure
wiring
is
rerouted
in

same
orientation
.

Tightening
Torques

"
CMP
sensor
to
cylinder
head
....
.
.
..
5
Nm
(3
.5
ft-Ib)

"
VANOS
oil
supply
pipe
to

VANOS
control
unit
...........
.
..
32
Nm
(24
ft-Ib)

"
VANOS
solenoid
to
VANOS

control
unit
...
.
.................
30
Nm
(22
ft-Ib)

Knock
sensors,
replacing

Knock
sensors
are
usedon
engines
with
Bosch
DME
M1
.7,

Bosch
DME
M3
.3
.1,
Bosch
DME
M5
.2,
and
Siemens
MS
41
.1

engine
management
systems
.
The
knocksensors
are
bolted
to
the
left
sideof
the
cylinder
block
and
monitor
the
combus-

tion
chamber
for
engine-damaging
knock
.
If
engine
knock
is

detected,
the
ignition
point
is
retarded
accordingly
via
the
en-

gine
control
module
.

CA
UTION-

"
Label
knock
sensorharness
connectors
before

disconnecting
them
.
The
connectors
must
not
be

interchanged
.
Engine
damage
may
result
if
the
sensors
are
monitoring
the
wrong
cytinders
.

"
Note
the
installed
angle
of
the
knock
sensoron
the

block
before
removing
it
.
Reinstall
the
sensor
in

the
same
position
.
Be
sure
to
usea
torque
wrench

when
tightening
the
sensormounting
bola

NOTE
-

"
On
M52
engines,
a
single
harness
connects
the
twosensors
to
the
main
harness
connector
.
The
shorter
cable
lead
fs
for
the
knock
sensor
for
cytinders
4,
5,
and
6
.

Tightening
Torque

IGNITION
SYSTEM



120-
7

0012730

Fig
.
12
.
Knock
sensor
mounting
bolt
on
front
left
side
of
cylinder

block
.

NOTE-

Knock
sensor
function
Is
monitoredby
the
On-Board
Diagnostic
system
.
If
a
knock
sensor
is
detected
to
be
faulty,
an
appropriatediagnostic
trouble
code
(DTC)
may
be
stored
in
memory
.
See
100
Engine-General
for
information
on
retrieving
DTCs
.

On
6-cylinder
engines,
the
knock
sensors
are
accessible
af-
ter
removing
the
intake
manifold
.
On
4-cylinder
engines,
the

upper
section
of
the
intake
manifold
should
be
removed
to
ac-

cess
the
sensors
.
See
Fig
.
12
.
NOTE-

Intakemanifold
removal
and
installation
procedures
are



"
Cylinder
no
.
1is
at
the
front
of
the
engine
.

covered
in
113
Cylinder
HeadRemoval
and
Installation
.

Ignition
Firing
Order

Ignition
Firing
Order

"
4-cylinder
engines
.....
..
...
.
..........
.1-3-4-2

"
6-cylinder
engines
...........
..
.
.
..
..
1-5-3-6-2-4

IGNITION
SYSTEM
SCHEMATICS

Fig
.
13
through
Fig
.
17
show
ignition
system
schematics

usedon
the
enginescoveredby
this
manual
.

IGNITION
SYSTEM
SCHEMATICS

120-8



IGNITION
SYSTEM

1



1
.0
GN



1
.0
Gl
.0
GN
I



Ign
coil



1
.0
GN
.

Tti



%ti



r,



_%ti
_



_
ice_
I



25



52
5524



51



54



56
I



Power
input



power
input

t



U



Engine
Control
Module
(Bosch
DME
Ml
.7)



II



Powerinput
Mainrelaycontrol
I
15
42



43



16442868
67



34
6
26



27
1
-----



__
V



_



--



_

~
8K



.35
BK
.35
13,1
1



.35
YE



1



.35
BK35
VE
.35

3



cyl
.1

1

11

E

S
2

1
.0
BR

2
.5
BR

Ign
.
coil
cyl
.
3



II

Ign
.
coil



Ign
.
coil
3



cyI
.
2



1
Y
_
Y
2



k
3



cyl
.
4

IGNITION
SYSTEM
SCHEMATICS

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



WIRING
COLOR
CODE
4
.0
GN

1
.0
BR'V
.

Camshaft
Knock
Sensor
Knock
Sensor



Position
(cyl
.1-2)
(cyl
.3-4)



Sensor

Fig
.
13
.
Bosch
DME
M1
.7
ignition
system
circuit
for
M42
engine
.

Ground
(RH
rearof
engine
compartment,
rear
of
shock
tower)

N[INS

Crankshaftlrpm
Position
Sensor

Battery
voltage
in
run
or
start
(vía
main
relay
terminal
87)

Ground
(RH
rearof
engine
compartment,
rearof
shock
tower)

5GN

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

Warning
:
Lethal
voltagepresent

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

'Y
Y

---------------------

0013087

121-
8



BATTERY,
STARTER,
ALTERNATOR

1f
the
solenoid
audibly
cliicks
but
the
motor
does
not
turn,



Starter,
removing
and
installing
switch
on
the
lights
andtum
the
key
to
the
start
position
.
lf
the



(6-cylinder
engine
with
lights
go
out
while
attempting
to
start,
the
battery
cable
may
be



manual
transmission)
loose
or
the
starter
may
have
a
short
circuit
.
If
the
lights
stay

on,the
solenoid
is
most
likely
atfault
.
The
starter
on
a
6-cylinder
car
with
manual
transmission
is

Starter,
removing
and
installing

(4-cylinder
engine)



1
.
Disconnect
negative
(-)
battery
cable
.

1
.
Disconnect
negative
(-)
cable
from
battery
.

CAUTION-

Prior
to
disconnecting
the
battery,
read
the
battery

disconnection
cautions
given
at
the
front
of
this

manual
on
page
viii
.

2
.
Remove
guide
tube
for
oil
dipstick
.

3
.
Raise
vehicle
.

WARNING
-

Make
sure
the
car
ís
stable
and
wefl
supported
at
all
times
.
Use
a
professional
automotive
lift
or
jack
stands
designed
forthe
purpose
.
A
floor
jack
is
not
adequate
support
.

4
.
Disconnect
wiring
from
starter
.

5
.
Remove
top
and
bottom
starter
bolts
.
Bottom
bolt
must

be
removed
from
below
car
.
Remove
starter
support

bracket,
if
applicable
.

removed
from
below
.

2
.
Raise
vehicle
.

3
.
Remove
reinforcing
cross
bracefromunder
transmís-

sion,
if
applicable
.

4
.
Remove
cover
from
fuel
filter
and
fuel
lines
on
left
side

underneath
car,
if
applicable
.
Detach
fuel
lines
and
har-

ness
connectors
from
retainingbrackets,
as
necessary

5
.
Disconnect
wiring
from
starter
.

6
.
Loosen
andremove
bolts
and
nuts
fastening
starter
to

transmission
bell
housing
and/or
engine
block
.
Remove

starter
supportbracket
.

7
.
Remove
starter
from
below
.

8
.
Check
starter
pinion
gear
and
flywheel
teeth
for
dam-

age
.

9
.
Installation
is
reverse
of
removal
.

6
.
Pull
starter
downward
and
turn
until
solenoid
is
at
top,



Tightening
Torques

then
remove
from
car
.



"
Re¡
nforcing
cross
brace

to
chassis
(M10)
..
...............
42
Nm
(31
ft-Ib)

7
.
>Check
starter
pinion
gear
and
flywheel
teeth
for
dam-



"
Starter
to
engine
block
(M10
bolt)
...
50
Nm
(37
ft-Ib)

age
.



"
Support
bracket
to
starter
(M5
nut)
...
5
Nm
(44
in-lb)

"
Support
bracket

8
.
Installation
is
reverse
of
removal
.



to
engine
block
(M10
bolt)
.........
47
Nm
(35
ft-Ib)

"
Wire
to
terminal
50
(M6
nut)
.........
6
Nm
(53
ín-Ib)

"
Wire
to
terminal
30
(M8
nut)
.........
12
Nm
(9
ft-lb)

Tightening
Torques

"
Starter
to
engine
block
(M10
bolt)
...
50
Nm
(37
ft-lb)

Wire
to
terminal
50
(M6
nut)
........
6
Nm
(53
in-lb)

"
Wire
toterminal
30
(M8
nut)
...
,
..:.
12
Nm
(9
ft-Ib)

STARTER
SERVICE

Starter,
removing
and
installing

(6-cylinder
engine
with

automatic
transmission)

The
starter
on
a
6-cylinder
car
with
automatic
transmission

ís
removed
from
above
.
It
is
necessary
to
remove
the
íntake

manifold
and
disconnect
a
number
of
electrical
harness
con-

nectors
.

1
.
Disconnect
negative
(-)
battery
cable
.

2
.
Remove
air
plenum
from
rear
of
engine
compartment
.

See640
Heating
and
Air
Conditioning
.

3
.
Remove
top
enginecovers
.
See
Fig
.
9
.

Fig
.
9
.



Remove
top
engine
cover
by
prying
out
plugs
and
removing
nuts
(A)
.
Make
sure
rubber
insulators
(B)
on
either
sideof
large
cover
do
not
fall
off
during
cover
removal
.

4
.
Remove
ignition
coil
harness
connectors
.
Remove
ground
connection
at
front
of
cylinder
head
.

5
.
Remove
two
retaining
bolts
and
lift
off
fuel
injector
har-
ness
connector
strip
.
Carefully
fold
away
all
harnesses
toward
right
side
of
engine
compartment
and
place
at
base
of
windshield
.
See
Fig
.
10
.

6
.
Remove
intake
manifold
.
See
113
Cylinder
Head
Re-
moval
and
Installation
.

7
.
Disconnect
wiring
from
starter
.

BATTERY,
STARTER,
ALTERNATOR



121-
9

Fig
.
10
.
Fuel
injection
harness
(A)
and
ignition
coíl
harness
connectors
(B)
being
lifted
off
engine
to
be
placed
at
base
ofwindshield
.
M50
engine
shown
.
Other
6-cylinder
engines
are
similar
.

8
.
Loosen
and
remove
bolts
and
nuts
fastening
starter
to
transmission
bell
housing
and/or
engine
block
.
Remove

starter
support
bracket
.

Fig
.
11
.
Starter
wiring
terminals
and
support
bracket(arrow)
.
Intake
manifold
has
been
removed
.

STARTER
SERVICE

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

130-20



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
.