1997 BMW 328i Throttle Position switch
[x] Cancel search: Throttle Position switchPage 176 of 759
130-
3
0
FUEL
INJECTION
Pin
Signal
Component/function
Signal
ECM
PIN
ASSIGNMENTS
Table
1.
ECM
Pin
Assignment-Bosch
DME
M3
.1
1
output
Fuel
pump
relay
control
Fuel
pump
relay
switches
with
engine
runningor
cranking
(crankshaft
position
Signal
mustbe
present
for
relay
switchover)
2
1
output
1
Idle
speed
control
valve
1
Pulsad
ground-
close
signal
(seealsopin29)
3
output
Fuel
injectorcontrol,
cyl
.
1
Pulsedground
(injection
pulsewidth
in
ms)
with
engine
running
4
output
Fuel
injectorcontrol,
cyl
.
3
Pulsedground
(injection
pulsewidth
in
ms)
with
engine
running
5
output
Fuel
injector
control,
cyl
.
2
Pulsedground
(injection
pulse
width
in
ms)
with
enginerunning
6
ground
Ground
Ground
for
fuel
injector
output
stages
7
vacant
-
-
8
output
Check
Engine
Check
éngine
lamp
control
ground
9
vacant
-
-
10
vacant
-
-
11
output
Throttle
valve
position
Load
signal
to
transmission
control
module
12
input
Throttle
position
sensor
Voltage
varies
with
throttle
position
13
output
Mass
air
flow
sensor
Air
flow
sensor
hotwire
burn
off
(voltage
for
0
.5
seconds
after
shutdown)
14
ground
Mass
air
flow
sensor
Ground
for
air
flow
sensor
15
vacant
-
-
16
input
Cylinder
identification
sensor
A/C
voltage
pulse
per
camshaft
revolution
(between
pin
16
and
44)
17
output
Fuel
consumption
(ti)
Fuel
consumption
output
(KVA
Signal)
to
instrument
cluster
18
vacant
-
-
19
vacant
-
-
20
vacant
-
-
21vacant
-
-
22
vacant
-
-
23
output
Ignition
control
(terminal
1),
cyl
.
no
.
2
Primary
Signal,
ignition
coil
cyl
.
no
.
2
24
output
Ignition
control
(terminal
1),
cyl
.
n
o
.
3
Primary
signal,
ignition
coil
cyl
.
no
.
3
25
output
Ignition
control
(terminal
1),
cyl
.
n
o
.
1
Primary
signal,
ignitioh
coil
cyl
.
no
.
1
26
input
Power
supply
(terminal
30)
Battery
voltage
(B+)
at
al¡
times
(terminal
30)
27
output
Main
relay
control
Main
relay
activation
(to
relay
terminal
85)
28
ground
Ground
Ground
for
ECM
and
sensor
shielding
29
output
Idle
speed
control
valve
Pulsed
ground-
open
signal
(see
also
pin
2)
30
vacant
-
-
31
output
Fuel
injector,cyl
.
no
.
5
Pulsedground
(injection
pulsewidth
in
ms),
cyl
.
no
.
5
32
output
Fuel
injector,cyl
.
no
.
6
Pulsedground
(injection
pulse
width
in
ms),
cyl
.
no
.
6
33
output
Fuel
injector,cyl
.
no
.
4
Pulsedground
(injection
pulsewidth
in
ms),
cyl
.
no
.
4
34
ground
Ground
Ground
for
output
stages
35
vacant
36
output
Evaporative
purgevalve
control
Pulsed
ground
with
engine
at
normal
temperature
and
varying
engine
load
37
output
Oxygen
sensor
heater
relay
control
Oxygen
sensor
heater
relayactivation
(ground
at
terminal
85)
38
vacant
-
-
39
vacant
-
-
40
vacant
-
41
input
Mass
air
flow
sensor
Voltage
(+)
42
vacant
-
-
43
ground
Ground
Ground
for
temperatura
sensors
(ECT
sensor,
IAT
sensor,
TP
sensor)
44
input
Cylinder
identification
sensor
A/C
voltagepulseper
camshaft
revolution
(between
pin
16
and
44)
Page 177 of 759
Table
i
.
ECM
Pin
Assignment-Bosch
DME
M3
.1
Pin
Signal
Component/function
2
ignal
FUEL
INJECTION
130-
3
1
45
vacant
-
46
vacant
-
-
47
vacant
-
-
48
output
A/C
compressor
control
A/C
compressor
disabled
via
compressor
control
relay
49
vacant
-
-
50
output
Ignition
control
(terminal
1),cyl
.
n
o
.
4
Primary
signal,
ignition
coil
cyl
.
n
o
.
4
51
output
Ignition
control
(terminal
1),cyl
.
n
o
.
6
Primary
signal,
ignition
coil
cyl
.
no
.
6
52
output
Ignition
control
(terminal
1),cyl
.
n
o
.
5
Primary
signal,
ignitioncoil
cyl
.
no
.
5
53
vacant
-
54
input
Power
supply
Battery
voltage
(+)
from
main
relay
terminal
87
55
ground
Ground
Ground
for
ignition
control
56
input
Power
supply
(terminal
15)
Batteryvoltage
(+)
with
key
on
or
engine
running
57
vacant
-
-
58
vacant
-
-
59
output
Throttleposition
sensor
Throttleposition
sensorsupply
voltage
(5
VDC)
60
input
Data
link
connector
Programming
voltage
61
vacant
-
-
62
vacant
-
-
63
vacant
-
-
64
input
Ignition
timing
intervention
from
A/T
control
module
(only
active
during
gearshift)
65
input
Automatic
transmission
(A/T)
range
switch
Transmission
park
or
neutral
signal
66
vacant
-
-
67
input
Engine
speed/crankshaft
position
sensor
Crankshaft
position/rpm
(voltage
(VAC)
between
pins
67
and
68)
68
input
Engine
speed/crankshaft
position
sensor
Crankshaft
position/rpm
(voltage
(VAC)
between
pins
67
and
68)
69
vacant
-
-
70
input
Oxygen
sensor
Oxygen
sensor
signal
(0-1
VDC
fluctuating
with
engine
running)
71
ground
Oxygen
sensor
Oxygen
sensor
signal
ground
72
vacant
-
-
73
input
Road
speed
Road
speed
signal
from
instrument
cluster
74
output
Engine
speed
(TD)
Engine
speed
(TD)
signalto
instrument
cluster
75
vacant
-
-
76
vacant
-
-
77
input
Intakeair
temperature
(IAT)
sensor
Intake
air
temperature
(0-5
V,
temperaturedependent)
78
input
Engine
coolant
temperature
(ECT)
sensor
Engine
coolant
temperature
(0-5V,
temperature
dependent)
79
vacant
-
-
80
vacant
-
-
81
input
On-boardcomputer
Drive-away
protection
enable
82
vacant
-
-
83
vacant
-
-
84
vacant
-
-
85
input
A/C
pressure
switch
From
Integrated
climate
control
module
via
A/C
pressure
switch
86
input
A/C
compressor
on
From
Integrated
climate
control
module
87
input
Diagnostic
connector
(RxD)
Diagnostic
RxD
(receive)signal
to
pin
15
in
Data
link
connector
88
input/output
Diagnostic
connector
(TxD)
Diagnostic
TxD
(transmit)
signal
to
pin
20
in
Data
link
connector
ECM
PIN
ASSIGNMENTS
Page 178 of 759
130-
3
2
FUEL
INJECTION
Pin
1
Signal
1
Component/function
1
Signal
1
output
Fuel
pump
relay
control
Fuel
pump
relay
switches
with
engine
running
or
cranking
(crankshaft
position
signal
must
be
present
for
relay
switchover)
2
output
Idle
speed
control
valve
Pulsed
ground-close
signal
(seealso
pin
29)
3
output
Fuel
ínjectorcontrol,
cyl
.
5
Pulsed
ground
(injection
pulsewidth
in
ms)
cyl
.
5
4
output
Fuel
injectorcontrol,
cyl
.
6
Pulsed
ground
(injection
pulsewidth
in
ms)
cyl
.
6
5
output
Fuel
injectorcontrol,
cyl
.
4
Pulsed
ground
(injection
pulsewidth
in
ms)
cyl
.
4
6
ground
Ground
Ground
for
fuel
injector
output
stage
7
output
Camshaft
actuator
(VANOS
solenoid)
control
Camshaft
actuator
(VANOS
solenoid)
8
output
Check
Engine
Instrument
cluster,
Check
Engine
lamp
9
vacant
-
-
10
vacant
-
-
11
output
Throttle
position
Throttle
angle
signal
to
A/T
control
module
12
vacant
-
-
13
input
Oxygen
sensor
Oxygen
sensor
signal
(0-1
VDC
fluctuating
with
engine
running)
14
input
Mass
air
flow
sensor
Mass
air
flow
sensor
15
ground
Ground
Ground
16
input
Crankshaft
position/rpm
sensor
Voltage
pulse
(VAC)
between
pin
16
and
43
(crank
position/rpm
sensor)
17
input
Camshaft
position
sensor
Halleffect
camshaft
sensor
18
vacant
-
-
19
vacant
-
-
20
vacant
-
-
21
vacant
-
-
22
vacant
-
-
23
output
Ignition
coil
control,
cyl
.
4
Ignition
coil
4
24
output
Ignition
coil
control,
cyl
.
6
Ignition
coil
6
25
output
Ignition
coil
control,
cyl
.
5
Ignition
coil
5
26
input
Power
supply
(terminal
30)
Battery
voltage(B+)
at
all
times
27
input
Main
relay
control
Main
relayactivation
(terminal
85)
28
ground
Ground
Ground
for
ECM
and
sensor
shielding
29
output
Idle
speed
control
valve
Pulsed
ground-open
signal
(seealsopin
2)
30
vacant
-
-
31
output
Fuel
injectorcontrol,
cyl
.
3
Injection
pulse
wicith
in
ms-cyl
.
3
32
output
Fuel
injectorcontrol,
cyl
.
2
Injection
pulse
wicith
in
ms-cyl
.
2
33
output
Fuel
injectorcontrol,
cyl
.
1
Injection
pulsewidth
in
ms-cyl
.
1
34
ground
Ground
Ground
for
remaining
output
stages
35
vacant
-
-
36
output
Evaporative
purge
valve
control
37
vacant
-
-
38
output
Oxygen
sensor
heater
relay
control
Oxygen
sensor
heater
relay
switchover
(terminal
85)
39
vacant
-
-
40
ground
Oxygen
sensor
Oxygen
sensor
signal
ground
41
input
Mass
air
flow
sensor
Mass
air
flow
voltage
signal
42
input
Vehicle
speed
Vehicle
speed
signal
from
instrument
cluster
43
input
Crankshaft
position/rpm
sensor
Voltage
pulse
(VAC)
between
pin16
and
43
44
ground
Ground
Ground
for
intake
air
temp
.
sensor,
engine
coolant
temp
.
sensor,
throttle
position
sensor
ECM
PIN
ASSIGNMENTS
Table
j
.
ECM
Pin
Assignment-Bosch
DME
M3
.3
.1
Page 179 of 759
Table
j.
ECM
Pin
Assignment-Bosch
DME
M3
.3
.1
Pin
~
Signal
1
Componentffunction
1
signal
FUEL
INJECTION
130-
33
45
ground
Ignition
circuit
shield
Ground
shieldfor
ignition
circuit
monitoring
46
output
Fuel
consumption
(KVA
signal)
To
instrument
cluster
47
output
Crankshaft
rpm
Engine
speed
(TD)
signal
to
instrument
cluster
48
output
A/C
compressor
control
A/C
compressor
relay
terminal
85
49
vacant
-
-
50
output
Ignition
coil
control,
cyl
.
1
Primary
signal,
ignition
coil
1
51
output
Ignition
coil
control,
cyl
.
2
Primary
signal,
ignition
coil
2
52
output
Ignition
coil
control,
cyl
.
3
Primary
signal,
ignition
coil
3
53
vacant
-
-
54
input
Power
supply
Battery
voltagefrom
main
relay
(terminal
87a)
55
ground
Ground
Ground
for
ignition
control
56
input
Power
supply
(terminal15)
Batteryvoltage
with
key
on
or
engine
running
57
input
Ignition
timing
intervention
From
A/T
control
module
58
vacant
-
-
59
output
Throttleposition
sensor
(TPS)
Voltage
supply
to
TPS
(5
VDC)
60
input
Programming
voltage
Data
link
connector
61
vacant
-
-
62
vacant
-
-
63
vacant
-
-
64
input
A/C
on
signal
From
integrated
climate
control
module
65
input
A/C
pressure
signal
From
integrated
climate
control
module
via
A/C
pressure
switch
66
input
On-board
computer
Drive-away
protection
enable
(starter
immobilization
relay)
67
vacant
-
-
68
vacant
-
-
69
input
Knock
sensor
#2
(cyl
.
4,5,
6)
Knock
sensor
#2
signal
70
input
Knock
sensor
#1
(cyl
.
1,2,
3)
Knock
sensor
#1
signal
71
ground
Ground
Ground
for
knock
sensors
and
shields
72
vacant
-
-
73
input
Throttleposition
sensor
(TPS)
Throttleposition
signal
74
vacant
-
75
vacant
-
-
76
vacant
-
77
input
Intakeair
temperatura
Intakeair
temperatura
sensor
(0-5
VDC)
78
input
Engine
coolant
temperature
Engine
coolant
temperature
sensor
(0-5
VDC)
79
vacant
-
80
vacant
-
-
81
input
Automatic
transmission
gear
positionlneutral
A/T
parkor
neutral
position
signal
safetyswitch
82
vacant
-
-
83
vacant
-
-
84
vacant
-
-
85
vacant
-
-
86
vacant
-
-
87
input
Diagnostic
connector
(RxD)
Diagnostic
RxD
(receive)
signal
to
pin
15
in
Data
link
connector
88
input/output
Diagnostic
connector
(TxD)
Diagnostic
TxD
(transmit)
signal
to
pin
20
in
Data
link
connector
ECM
PIN
ASSIGNMENTS
Page 180 of 759
130-
34
FUEL
INJECTION
Pin
i
Signal
1
Component/function
1
Signal
1
output
Oxygen
sensor
(monitoring
sensor)heater
Oxygen
sensor
heater
control
(switched
ground)
2
output
Idle
speed
control
valve
Pulsed
ground-close
signal
(see
also
pin
29)
3
output
Fuel
injector
control,
cyl
.
1
Pulsed
ground
(injection
pulsewidth
in
ms)
cyl
.
1
4
output
Fuel
injector
control,
cyl
.
4
Pulsed
ground
(injection
pulse
width
in
ms)
cyl
.
4
5
not
used
-
-
6
ground
Ground
Ground
for
fuel
injector
output
stage
7
not
used
-
8
1
output
1
Check
Engine
1
Instrument
cluster,
Check
Engine
lamp
9
not
used
-
-
10
input
Electronic
immobilizer
control
(EWS
II)
Electronic
immobilizer
control
(EWS
II)
module
11
output
Automatic
climate
control
Automatic
climate
control,
to
evaporator
controlier
12
not
used
-
-
13
not
used
-
-
14
not
used
-
-
15
not
used
-
-
16
input
Intake
air
temperature
Intake
air
temperature
Signal
17
input
Mass
air
flow
meter
Intake
air
signal
18
not
used
-
-
19
input
Oxygen
sensor
(monitoring
sensor)
Oxygen
sensor
control
20
output
Crankshaft/rpm
sensor
Crankshaft/rpm
sensor
control
21
input
Camshaft
position
sensor
Camshaft
position
signal
22
output
Ignition
coil
control,
cyl
.
3
Primary
signal,
ignitioncoil
3
23
output
Ignition
coil
control,
cyl
.
4
Primary
signal,
ignitioncoil
4
24
not
used
-
-
25
not
used
-
-
26
input
Power
supply
(terminal
30)
Battery
voltage
(B+)
at
al¡
times
27
input
Main
relay
control
Main
relay
activation
(terminal
85)
28
ground
Ground
Ground
for
ECM
and
sensor
shielding
29
output
Idle
speed
control
valve
Pulsed
ground-open
signal
(seealsopin
2)
30
output
Oxygen
sensor
(monitoring
sensor)
heater
Oxygen
sensor
heater
control
(switched
ground)
31
output
Fuel
injectorcontrol,
cyl
.
3
Pulsed
ground
(injection
pulsewidth
in
ms)
cyl
.
3
32
output
Fuel
injector
control,
cyl
.
2
Pulsed
ground
(injection
pulsewidth
in
ms)
cyl
.
2
33
I
not
used
40
input
Knock
sensor
#2
(cyl
.
3,4)
Knock
sensor
#2
signal
41
not
used
-
-
42
input
Vehicle
speed
Vehicle
speed
signal
from
instrument
cluster
43
not
used
-
-
44
output
Throttleposition
sensor
(TPS)
Throttleposition
reference
signal
ECM
PIN
ASSIGNMENTS
Table
k
.
ECM
Pin
Assignment-Bosch
DME
M5
.2
34
ground
Ground
Ground
for
ECM/
output
stages
35
not
used
-
-
36
input
A/C
compressor
relay
A/C
compressor
relay
control
37
not
used
-
-
38
not
used
-
-
39
not
used
-
-
Page 181 of 759
Table
k
.
ECM
Pin
Assignment-Bosch
DME
M5
.2
(continued)
Pin
I
Signal
1
Componentltunction
1
Signal
45
I
output
I
Mass
air
flow
meter
I
Intake
airSignal
46
output
Oxygen
sensor
(monitoring
sensor)
Oxygen
sensor
control
47
not
used
-
48
not
used
-
49
output
Ignition
coil
control,
cyl
.
1
Primary
signal,
ignition
coil
1
50
output
Ignition
coil
control,
cyl
.
2
Primary
signal,
ignition
coil
2
51
not
used
-
52
not
used
-
53
input
Throttleposition
sensor
Throttleposition
Signal
54
input
Power
supply
Batteryvoltage
from
main
relay
(terminal
87)
55
ground
Ground
Ground
for
ECM
56
input
Power
supply
(terminal
15)
Battery
voltage
with
key
on
or
engine
running
57
output
Activate
cooling
fan
(man
.
trans
.)
control
Normal
speed
relay
58
not
used
-
-
59
not
used
-
-
60
input
Programming
voltage
Programming
voltage
via
data
link
connector,
pin
18
61
output
Evaporative
emissionvalve
Evaporative
emission
valve
control
62
vacant
-
-
63
output
Fuel
pump
relay
Fuel
pump
relay
control
64
not
used
-
65
not
used
-
-
66
not
used
-
-
67
not
used
-
-
68
input
Signal
above
80°C(man
.
tran
.)
Double
temperature
switch
69
input
Automatic
climate
control
Automatíc
climate
control
70
input
Knock
sensor
#1
(cyl
.
1,2)
Knock
sensor
#1
Signal
71
ground
Ground
Ground
for
analog
signals
and
knock
sensors
72
not
used
-
-
73
not
used
-
-
74
input
Engine
coolant
temperature
sensor
Engine
coolant
temperatura
Signal
75
not
used
-
-
76
not
used
-
-
77
output
Oxygen
sensor
(regulating
sensor)
Oxygen
sensor
control
78
input
Crankshaft/rpm
sensor
Crankshaft
position/rpmSignal
79
input
ABS
or
traction
control
ABS
or
AST
control
80
input
Engine
speed
Engine
speed
Signal
81
not
used
-
-
82
not
used
-
-
FUEL
INJECTION
130-
3
5
83
input
On-board
computar
From
On-boardcomputer
(terminal
4)
84
not
used
-
-
85
not
used
-
-
86
not
used
-
-
87
input
Diagnostic
connector
(RxD)
Diagnostic
RxD
(receive)signal
to
pin
15
in
Data
link
connector
88
output
I
Diagnostic
connector
(TxD)
Diagnostic
TxD
(transmit)
signal
to
pin
17in
Data
link
connector
ECM
PIN
ASSIGNMENTS
Page 182 of 759
130-
3
6
FUEL
INJECTION
Pin
1
Signal
1
Componentffunction
1
Signal
1
output
Ignition
coil
control,
cyl
.
2
Primary
signal,
ignition
coil
2
2
output
Ignition
coil
control,
cyl
.
4
Primary
signal,
ignitioncoil
4
3
output
Ignition
coil
control,
cyl
.
6
Primary
signal,
ignition
coil
6
4
ground
Ground
Ground
5
output
Fuel
injectorcontrol,
cyl
.
2
Pulsed
ground
(injection
pulse
width
in
ms)
cyl
.
2
6
output
Fuel
injectorcontrol,
cyl
.
1
Pulsed
ground
(injection
pulse
width
in
ms)
cyl
.
1
7
output
Mass
air
flow
meter
Mass
air
meter
signal
8
input
Mass
air
flow
meter
Mass
air
meter
signal
9
output
Instrument
cluster
Fuel
consumption
signal
10
output
Engine
coolant
temperature
(ECT)
sensor
ECT
signal
11
output
Fueltankpressure
sensor
Fueltankpressure
sensor
control
12
input
Throttleposition
sensor
(TPS)
Throttleposition
signal
13
-
14
input
Intake
air
temperature
(IAT)
sensor
Intake
air
temperature
signal
15
Traction
control
AST
module
16
input
Automatic
climate
control
Automatic
climate
control
17
18
input
Electronic
immobilizer
control
(EWS
II)
Electronic
immobilizer
control
(EWS
II)
module
19
Automatic
climate
control
Automatic
climate
control
20
-
Instrument
cluster
Instrument
cluster
21
output
Camshaft
actuator
(VANOS
solenoid)
control
Camshaft
actuator
(VANOS
solenoid),
switched
ground
22
output
Fuel
injectorcontrol,
cyl
.
3
Pulsed
ground
(injection
pulse
width
in
ms)
cyl
.
3
23
Fuel
injectorcontrol,
cyl
.
6
Pulsed
ground
(injection
pulse
width
in
ms)
cyl
.
6
24
Fuel
injectorcontrol,
cyl
.
4
Pulsed
ground
(injection
pulse
width
in
ms)
cyl
.
4
25
output
Oxygen
sensor
heater
control
Oxygen
sensor
heater
ground
26
input
Power
supply
(terminal
30)
Battery
voltage(B+)
at
all
times
27
output
Idle
speed
control
valve
Pulsed
ground-open
signal
(see
also
pin
53)
28
ground
Ground
Ground
29
output
Ignition
coil
control,
cyl
.
1
Primary
signal,
ignition
coíl
1
30
output
Ignition
coil
control,
cyl
.
3
Primary
signal,
ignition
coil
3
31
output
Ignition
coil
control,
cyl
.
5
Primary
signal,
ignition
coil
5
32
ground
Ground
Ground
33
output
Fuel
injector
control,
cyl
.
5
Pulsedground
(injection
pulsewidth
in
ms)
cyl
.
5
34
ground
Ground
Ground
35
output
Secondary
air
injection
Secondary
air
injection
pump
relay
control
36
output
Engine
speed
output
Engine
speed
signal
37
-
38
ground
Knock
sensor
Shielding
for
knock
sensors
39
output
Intake
air
temperature
sensor
(IAT
Sensor)
Voltagesupply
to
IAT
sensor
and
ECT
sensorEngine
coolant
temperature
(ECT)
sensor
40
output
Crankshaft
position
sensor
(Hall
effect)
Crankshaft
position
sensor
control
41
ground
Camshaft
position
(CMP)
sensor
Shielding
for
CMP
sensor
42
output
Throttle
position
sensor
(TPS)
TPS
ground
43
input
Camshaft
position/rpm
sensor
Camshaft
position/rpm
sensor
control
44
output
Throttle
position
sensor
(TPS)
Voltagesupply
to
TPS
(5
VDC)
45
Traction
control
AST
module
46
-
Instrument
cluster
Instrument
cluster
ECM
PIN
ASSIGNMENTS
Table
I.
ECM
Pin
Assignment-Siemens
DME
MS
41
.1
Page 253 of 759
NOTE-
The
traction
control
system
referred
to
as
AST
(all
sea-
son
traction)
may
also
be
referred
to
as
ASC
(Automat-
ic
Stability
Control)
and
ASC+T
(Automatic
Stability
Control+Traction)
.
The
AST
system
improves
traction
by
electronically
apply-
ing
the
rear
brakes
when
therear
drive
wheels
are
spinning
at
a
faster
rate
than
the
front
wheels
.
The
combined
ABS/AST
control
module,
operating
through
the
ABS
hydraulic
control
unit,
modulates
braking
force
at
therear
wheels
.
In
addition,
AST
uses
retarded
ignition
timing
and
an
auxil-iary
engine
throttle
plate
to
reduceengine
torque
and
maintain
vehicle
stability
.
The
auxiliary
throttle
plate
is
held
open
by
spring
pressure
.
The
AST
system
actívates
the
auxiliary
throttie
position
motor
(ADS)
to
cose
the
AST
throttle
as
needed
.
This
reduces
the
volume
of
engine
intake
air
.
Due
to
the
throttle
closing
very
rapidly
during
AST
operationthe
driver
cannot
increase
theengine
power
output
regardless
of
how
far
theaccelerator
pedal
is
pushed
to
the
floor
.
The
auxiliary
throttle
plate
is
placed
ahead
of
the
conven-
tional
throttle
plate
in
the
throttle
body
.
Traction
control
also
comes
into
operationduringdecelera-
tion
.
Decelerating
on
snowy
or
icy
road
surfaces
can
lead
to
rear
wheel
slip
.
If
a
rear
wheel
startsto
drag
or
lock
up
when
the
throttle
is
closed
rapidly
orduringdownshifting,the
AST
system
can
limit
the
problem
by
advancing
the
ignition
timing
.
A
switch
on
the
center
console
is
used
to
togglethe
AST
on
or
off
.
The
AST
system
is
designed
to
be
maintenance
free
.
There
are
no
adjustments
that
can
be
made
.
Repair
and
trouble-
shooting
of
the
AST
system
requires
special
test
equipment
andknowledgeand
should
be
performed
only
by
an
autho-
rized
BMW
dealer
.
Table
a
lists
theconditions
indicated
by
the
AST
indicator
light
in
the
instrument
cluster
SUSPENSION,
STEERING
AND
BRAKES-GENERAL
300-5
Tablea
.
AST
Indicator
Lamp
Function
Indicator
lamp
1
Condition
1
Comment
Light
on
Normal
AST
start-
Automatic
AST
up
self-test
Light
off
AST
monitoring
Automatic
AST
op-
mode
eration
Press
AST
button,
AST
off
(disabled)
Rocking
the
car
tolight
comes
on
getout
of
snow
or
other
loose
surface
Driving
with
snow
chains
Press
AST
button
:
AST
monitoring
Automatic
AST
op-
light
goes
out
I
mode
eration
Light
flashes
AST
active
mode
I
Normal
AST
oper-
ation
as
it
controls
wheel
speed
Light
stays
on
af-
Defect
in
AST
Consult
BMW
ter
start
up
or
dealer
for
diagno-
comes
on
while
sis/repair
driving
(Vehicle
operation
remains
normal)
WARNING
-
Even
a
car
with
AST
is
subject
to
the
normal
physi-
cal
laws
.
Avoid
excessive
speeds
for
the
road
con-
ditions
encountered
.
CAUTION-
"
If
the
tires
on
the
carare
of
different
makes,
the
AST
system
may
over-react
.
Only
fit
tires
of
the
same
make
and
tread
pattem,
"In
adverse
conditions,
such
as
trying
to
rock
the
car
outof
deep
snow
or
another
soft
surface,
or
when
snow
chainsare
fitted,
it
is
advisable
to
switch
off
AST
and
allow
the
cars
driveline
to
op-
erate
conventionally
.
INTEGRATED
SYSTEMS