2009 VOLVO S80 sensor

04 Comfort and driving pleasure
Adaptive Cruise Control–ACC (option)
04``165 Introduction
Adaptive Cruise Control (ACC) is an optional
system designed to assist the driver by main-
taining a set speed or a set distance to the
vehicle ahead. It is primarily intended for use
on long straight roads in steady traffic, such as
on highways and other main roads.
WARNING
•
Do not use the adaptive cruise control
system in demanding driving conditions
such as city traffic, winding roads, at
intersections, on slippery surfaces, in
poor visibility, heavy rain, etc.
•
Maintenance of cruise control compo-
nents must only be performed by an
authorized Volvo workshop.
WARNING
•
Adaptive cruise control cannot cover all
driving situations and traffic, weather
and road conditions. The Function sec-
tion provides information about limita-
tions that the driver must be aware of
before using the adaptive cruise con-
trol.
•
This system is designed to be a supple-
mentary driving aid. It is not, however,
intended to replace the driver's atten-
tion and judgement. The driver is
responsible for maintaining a safe dis-
tance and speed and must intervene if
adaptive cruise control does not main-
tain a suitable speed or suitable dis-
tance.
Function
G021412
Function overview
Warning light, braking by driver requiredControlsRadar sensor in front grille
Adaptive cruise control consists of:
•
A cruise control system to maintain a set
speed
•
A system to maintain a set distance to the
vehicle ahead (expressed as a time inter-
val. For example, you can choose to
remain approximately 2 seconds behind
the vehicle ahead).

04 Comfort and driving pleasureAdaptive Cruise Control–ACC (option)
04166
WARNING
•
Adaptive cruise control is not a collision
avoidance system. The driver is always
responsible for applying the brakes if
the system does not detect another
vehicle.
•
Adaptive cruise control does not react
to slow moving or stationary vehicles.
The distance to the vehicle ahead (in the same
lane) is measured by a radar sensor. Your vehi-
cle's speed is regulated by acceleration and
braking. The brakes may emit a sound when
they are being modulated by the adaptive
cruise control system. This is normal.
WARNING
The brake pedal moves when the adaptive
cruise control system modulates the
brakes. Do not rest your foot under the
brake pedal.The adaptive cruise control system is designed
to follow the vehicle ahead of you in the same
lane, at a set time interval.
If the radar sensor has not detected a vehicle
ahead, the system will then attempt to maintain
the set speed. This is also the case if the speedof the vehicle ahead exceeds the speed that
you have set.
The adaptive cruise control system is designed
to smoothly regulate speed. However, the
driver must apply the brakes in situations that
require immediate braking. This applies when
there are great differences in speed between
vehicles, or if the vehicle ahead brakes sud-
denly.
WARNING
Due to limitations in the radar sensor, brak-
ing may occur unexpectedly or not at all,
see page 168.Adaptive cruise control can only be activated
at speeds above 20mph (30 km/h). If speed
falls below 20 mph (30 km/h) or if engine speed
(rpm) becomes too low, adaptive cruise control
disengages and will no longer modulate the
brakes. In situations when adaptive cruise con-
trol cannot be activated
Cruise Control
Unavailable
is shown in the display, see
page 170.
WARNING
When adaptive cruise control disengages,
the brakes will not be modulated automati-
cally. The driver must assume full control
over the vehicle.Warning light-driver braking requiredAdaptive cruise control has a braking capacity
that is equivalent to approximately 30% of the
vehicle's total braking capacity. In situations
requiring more brake force than ACC can pro-
vide, if the driver does not apply the brakes, an
audible signal will sound and a red warning
light will illuminate in the windshield to alert the
driver to react.
NOTE
Strong sunlight, reflections, extreme light
contrasts, the use of sunglasses, or if the
driver is not looking straight ahead may
make the visual warning signal in the wind-
shield difficult to see.
WARNING
Cruise control only warns of vehicles
detected by the radar sensor, see
page 168. In some cases there may be no
warning or the warning may be delayed. The
driver should always apply the brakes when
necessary.

04 Comfort and driving pleasure
Adaptive Cruise Control–ACC (option)
04``167 Operation
G027123
Controls and display
Activate and resume settings, increase
speedStandby mode, on/offSet time intervalActivate and set a speedSet speed (parentheses indicate standby
mode)Time interval while it is being setTime interval after it has been set
Engaging the cruise control functionBefore ACC can be used, it must first be put in
standby mode. To do so, press
. The symbol
illuminates in the display and (---) indicate
that ACC is in standby mode.Setting a speedUse the
or
buttons to store (set) the
vehicle's current speed. The set speed, for
example 55 mph, is shown in the display.
NOTE
Adaptive cruise control cannot be engaged
at speeds below 20 mph (30 km/h).
The “car” symbol illuminates
on the left side of the display
when the radar sensor
detects another vehicle
ahead. The distance to a vehi-
cle ahead is only regulated
when this symbol is illumi-
nated.
Adjusting the set speedAfter a speed has been set, it can be increased
or decreased by using the
or
buttons.
When the system is in active mode, the
but-
ton has the same function as
, but results in
a smaller increase in speed.
NOTE
•
If one of the adaptive cruise control but-
tons is pressed for more than approxi-
mately one minute, ACC will be deacti-
vated. The engine must then be
switched off and restarted to reset ACC.
•
In some situations cruise control cannot
be activated.
Cruise Control
Unavailable is shown in the display,
see page 170.
Setting a time intervalThe set time interval to vehicles ahead is
increased with
and decreased with
.
The current time interval is shown briefly in the
display following adjustment.
Five different time intervals
can be selected and are
shown in the display as 1–5
horizontal bars. The greater
the number of bars, the longer
the time interval. At low
speeds, when the distance to
the vehicle ahead is short, ACC increases the
time interval slightly. In order to follow the vehi-
cle ahead as smoothly as possible, ACC allows
the time interval to vary considerably in certain
situations.

04 Comfort and driving pleasureAdaptive Cruise Control–ACC (option)
04168
WARNING
•
Only use a time interval that is suitable
in current traffic conditions.
•
A short time interval gives the driver lim-
ited reaction time if an unexpected sit-
uation occurs in traffic.
The number of bars indicating the selected
time interval are shown while the setting is
being made and for several seconds afterward.
A smaller version of the symbol is then shown
to the right in the display. The same symbol is
also displayed when Distance Alert is acti-
vated, see page 172 .Deactivating and resuming settingsCruise control is deactivated, either with a
short press on
, or by action taken by the
driver, such as braking, etc. The set speed, for
example 55 mph, is then shown in parenthe-
ses. Speed and time interval are resumed by
pressing
.
WARNING
There may be a significant increase in speed
after the
button has been pressed.
A short press on
in standby mode or a long
press in active mode deactivates cruise con-trol. The set speed is then cleared and cannot
be resumed.
When ACC is activated, the vehicle’s speed
increases by approximately 1 mph (1 km/h)
each additional time
is pressed.
Deactivation due to action by the driverACC is deactivated:•
when the brakes are applied
•
if the gear selector is moved to N
•
if the accelerator pedal is depressed for an
extended period.NOTE
If the accelerator pedal is only depressed for
a short time, such as when passing another
vehicle, ACC is deactivated temporarily and
is reactivated when the pedal is released.Automatic deactivationAdaptive cruise control is linked to other sys-
tems such as ABS, the stability and traction
control system (DSTC), and the Distance Alert
System. If any of these systems are not func-
tioning properly, adaptive cruise control is
automatically deactivated.
In the event of automatic deactivation a signal
will sound and the message
Cruise Control
Canceled
is shown in the display. The drivermust then intervene and adapt the vehicle's
speed to the surrounding traffic.
Automatic deactivation may be caused if:
•
the vehicle's speed falls below 20 mph
(30 km/h)
•
the wheels lose traction or if the anti-lock
brake system (ABS) is activated
•
brake temperature is high
•
engine speed (rpm) is too low
•
the radar sensor is obstructed by, for
example, wet snow or rain.
The radar sensor and its limitationsThe radar sensor is used by both Adaptive
Cruise Control and the Collision Warning Sys-
tem with Auto-brake. It is designed to detect
cars or larger vehicles driving in the same
direction as your vehicle.
WARNING
Accessories or other objects, such as extra
headlights, must not be installed in front of
the grille.
Modification of the radar sensor could make
its use illegal.The radar sensor's capacity to detect vehicles
ahead is impeded:

04 Comfort and driving pleasure
Adaptive Cruise Control–ACC (option)
04``169
•
if the radar sensor is obstructed and can-
not detect other vehicles, for example in
heavy rain, or if snow or other objects are
obscuring the radar sensor.NOTE
Keep the area in front of the radar sensor
clean.•
if the speed of vehicles ahead is signifi-
cantly different from your own speed.WARNING
The radar sensor has a limited field of vision.
In some situations it may detect a vehicle
later than expected or not detect vehicles at
all.
G021414
Radar sensor field of vision (gray)
In certain situations, the radar sensor can-
not detect vehicles at close quarters, for
example a vehicle that suddenly enters thelanes between your vehicle and the one
that the system has already detected.
Small vehicles, such as motorcycles, or
vehicles not driving in the center of the lane
may remain undetected.In curves, the radar sensor may detect the
wrong vehicle or lose a detected vehicle
from view.
Fault tracing and actionsIf the message
Radar blocked See manual
is
displayed, this means that the radar signals
from the sensor have been obstructed and that
a vehicle ahead cannot be detected.
This, in turn, means that the functions of the
ACC, Distance Alert, and Collision Warning
System with Auto-brake will not function.
The table lists possible causes for this mes-
sage being displayed, and suitable actions.
Cause
Action
The surface of the radar in the grille is dirty or obstructed in some way.
Clean the radar surface, or remove the object causing the obstruction.
Heavy rain or snow is interfering with the radar signals.
No action possible. Heavy precipitation may affect the function of the
radar.

04 Comfort and driving pleasureAdaptive Cruise Control–ACC (option)
04170
Cause
Action
Swirling water or snow from the surface of the road may interfere with
the radar signals.
No action possible. A very wet or snow-covered road surface may affect
the function of the radar.
The surface of the radar is clean but the message remains in the display.
Wait a short time. It may take several minutes for the radar to detect that
it is no longer obstructed.
Symbols and messages in the displaySymbol
Message
DescriptionStandby mode or active mode when no other vehicle has been detected.Active mode with a detected vehicle to which ACC is adapting speed/distance.Time interval while it is being set.Time interval after it has been set.
Turn on DSTC
to enable Cruise
ACC cannot be activated until the stability system (DSTC) has been activated. see page 154 for more
information on DSTC.
Cruise control canceled
ACC has been automatically switched off.
The driver must regulate the vehicle’s speed/distance to the vehicle ahead.
Cruise control unavailable
ACC cannot be activated. This may be due to:•
high brake temperature
•
the radar sensor is obstructed (by heavy rain, snow, etc.)

04 Comfort and driving pleasure
Adaptive Cruise Control–ACC (option)
04
171
Symbol
Message
Description
Radar blocked
See manual
ACC has been temporarily disconnected because the radar is obstructed in some way and cannot
detect other vehicles.
see page 168 for information on the radar sensor’s limitations..
Cruise control
Service required
ACC is not functioning.
Contact a trained and qualified Volvo service technician.

04 Comfort and driving pleasure
Distance alert
04``173
also displayed when Adaptive Cruise Control is
activated.
NOTE
•
The higher your vehicle’s speed, the
greater the distance to the vehicle
ahead, measured in feet (meters), for a
given time interval.
•
The set time interval is also used by
Adaptive Cruise Control, see page 167.WARNING
Only use a time interval that is suitable in
current traffic conditions.
LimitationsThe Distance Alert function uses the same
radar sensor used by Adaptive Cruise Control
and the Collision Warning system. See page
168 for more information on the radar sensor’s
limitations.
NOTE
Strong sunlight, reflections, extreme light
contrasts, the use of sunglasses, or if the
driver is not looking straight ahead may
make the visual warning signal in the wind-
shield difficult to see.
WARNING
•
Bad weather or winding roads may
affect the radar sensor’s capacity to
detect vehicles ahead.
•
The size of the vehicle ahead, such as a
motorcycle, may also make it difficult to
detect. This may result in the warning
light illuminating at a shorter distance
than the one that has been set, or that
the light will not come on at all.
Symbol
Message
DescriptionTime interval while it is being set.Time interval after it has been set.