boot BMW M3 2010 Owners Manual

Reference
At a glance
Controls
Driving tips
Mobility
55
Active cruise control*
The concept
With active cruise control, you can select a
desired speed which is not only automatically
maintained when driving on open roadways, but
also varied to maintain a selected distance set-
ting as slower traffic is encountered.
Active cruise control is a technological advance
over the familiar cruise control and is a welcome
relief from the constant adjustment of speed
that can accompany driving in traffic on high-
ways or other high-speed thoroughfares. Espe-
cially on longer trips, the system can reduce
fatigue and tension, while increasing your
enjoyment of driving. Please use it safely and
responsibly.
Within the limits of its capability, the system
automatically adapts the car's speed to that of a
slower vehicle in front of you. You can specify
the distance to be maintained from the vehicle
in front in four stages. For safety reasons, the
distance is speed-dependent. Based on your
selected distance setting, the system automat-
ically decreases the throttle setting and lightly
applies the brakes if necessary. The vehicle
brake lamps will automatically illuminate to sig-
nal a following driver to take action. In addition,
it may be necessary for the vehicle or the driver
to downshift, depending on the kind of trans-
mission your vehicle is equipped with, to main-
tain the distance setting selected. If the vehicle
ahead speeds up or when the lane ahead
becomes clear, your vehicle will accelerate to
the speed you have selected by increasing the
throttle setting and shifting gears automatically
or by the driver as needed. Your selected speed
will be held when driving downhill, too.
Since this active cruise control system is a new
technology and operates differently from con-
ventional cruise control systems which you may
be accustomed to, you are strongly urged to
read all of the pages relating to this system
before use. Pay special attention to the System
limitations section beginning on page59.
Braking sensation
>If you step on the brake pedal while the sys-
tem is braking, pedal sensation will be
slightly different from the usual.
>Possible noises during automatic braking
are normal.
Manual transmission
You can shift gears while cruise control is acti-
vated. The system is deactivated when you
drive at very low engine speeds for an extended
period.
Range of applications
The minimum desired speed is 20 mph or
30 km/h, the maximum desired speed is
110 mph or 180 km/h.
As with conventional cruise control sys-
tems, active cruise control in no way
diminishes or substitutes for the driver’s own
personal responsibility, alertness and aware-
ness in adjusting speed, braking or otherwise
controlling the vehicle. The driver should
decide when to use the system on the basis of
road, traffic, visibility, and weather conditions.
Active cruise control is intended for use on
highway-type roadways where traffic is moving
relatively smoothly. Do not use this system in
city driving; heavy traffic such as during rush
hour; on curvy, winding roads, slippery roads or
roads with sharp curves such as highway off-
ramps; during inclement weather such as snow,
strong rain or fog; or when entering inter-
changes, service/parking areas or toll booths.
It is also important to regulate your vehicle's
speed and distance setting within applicable
legal limits. Always be ready to take action or
apply the brakes if necessary, especially when
the system is actively following a vehicle in front
of you. Otherwise, driving situations could
result that pose the risk of accidents.<

Reference
At a glance
Controls
Driving tips
Mobility
59
System limitations
Always remember that the range and abil-
ity of the system does have physical limi-
tations. It will not apply the brakes or decelerate
your vehicle when there is a slow-moving vehi-
cle, stopped vehicle or stationary object ahead
of you, as for example, at a traffic light or a
parked vehicle. Also, the system does not react
to oncoming traffic, pedestrians or other types
of potential traffic such as a rider on horseback.
It is also possible that the system may not
detect smaller moving objects such as motor-
cycles or bicycles. Be especially alert when
encountering any of these situations as the sys-
tem will neither automatically brake, nor provide
a warning to you. Also, be aware that every
decrease in the distance setting allows your
vehicle to come closer to a vehicle in front of
you and requires a heightened amount of alert-
ness.<
Active cruise control is not and must not
be used as a collision avoidance/warning
system.<
If while your vehicle is actively following a vehi-
cle in front of you and the vehicle ahead speeds
up or the lane ahead becomes clear, then your
vehicle will accelerate to the speed you have
selected. Be aware that changing to a clear,
unobstructed lane will also result in your vehicle
accelerating.
Be certain to deactivate the system when
you pull into an exit lane for a highway off-
ramp.<
Also, vehicles traveling in a staggered manner
on a highway may cause a delay in the system's
reaction to a vehicle in front of you or may cause
the system to react to a vehicle actually in the lane next to you. Always be ready to take action
or apply the brakes if necessary.
While active cruise control is capable of
braking your vehicle automatically when
you approach a slower vehicle ahead, it is
important to be aware that the ability of the sys-
tem to apply the brakes is also limited, e.g.
when you reduce your desired speed sharply.
The system cannot stop your vehicle. It uses
only a portion of braking system capacity and
does not utilize the full capacity of the vehicle
braking system. Therefore, the system cannot
decrease your speed for large differences in
speed between your vehicle and the vehicle
ahead. Examples: when you approach a vehicle
traveling at a much lower speed than your own
speed such as approaching a toll booth or when
a much slower vehicle cuts in front of you at
close range.<
Active cruise control can only decelerate the
vehicle to approx. 20 mph or 30 km/h.
Swerving vehicles
When a vehicle moves from an adjacent lane
into your lane, active cruise control will not rec-
ognize this vehicle until it is fully in your lane
ahead of your vehicle.