2011 VOLVO XC70 brake sensor

04 Comfort and driving pleasure
Collision warning with Auto-brake*
04
174* Option/accessory, for more information, see Introduction.
Introduction
Collision Warning with Auto-brake is designed
to assist the driver if there is a risk of a collision
with a vehicle ahead that is at a standstill or
moving in the same direction as your vehicle.
Collision Warning consists of the following
three functions:
•Collision Warning warns the driver of a
potential collision situation.
•Brake Support helps the driver brake effi-
ciently in a critical situation.
•Auto-brake brakes the vehicle automati-
cally if a collision cannot be avoided. Auto-
brake cannot prevent a collision but can
reduce the speed at which a collision
occurs.
WARNING
The auto-brake function cannot prevent a
collision but instead is intended to reduce
speed at the moment of impact. For full
braking effect, driver must apply the brakes.
WARNING
•Collision Warning does not work in all
driving, traffic, weather and road condi-
tions. It does not react to vehicles not
traveling in the same direction as your
vehicle.
•The collision warning system is not
designed to detect pedestrians.
•Warnings are only provided when the
risk of collision is high. The "Function"
section provides information about lim-
itations that the driver must be aware of
before using Collision Warning.
•The auto-brake function can help
reduce the speed at impact but the
driver should always apply the brakes
for the best possible braking effect,
even if auto-brake is actively applying
the brakes.
•Never wait for a collision warning. This
system is designed to be a supplemen-
tary 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, even when the colli-
sion warning system is in use.
•Maintenance of the Collision Warning
system's components must only be
performed by a trained and qualified
Volvo technician.
Function
G017382
Function overview
Visual warning signal, collision risk
Radar sensor
Camera
Collision WarningThe radar sensor and the camera work
together to detect stationary vehicles and vehi-
cles that are moving in the same direction as
your vehicle. If there is a risk of collision, the
driver is alerted by a flashing red warning light
and an audible warning signal. Collision warn-
ing is active at speeds above 5 mph (7 km/h).

04 Comfort and driving pleasure
Collision warning with Auto-brake*
04
176* Option/accessory, for more information, see Introduction.
NOTE
•When Adaptive Cruise Control is used,
the warning light and signal will be used
by that function, even if the warnings
provided by Collision Warning have
been deactivated by the driver.
•In situations where traffic is moving at
considerably different speeds, or if the
vehicle ahead brakes suddenly, warn-
ings may be considered to be late, even
if the setting
Long has been selected.
Checking settingsThe current Collision Warning settings can be
checked by going into the menu system at Car
settings
Collision warning settings.
See page 124 for more information on the
menu system.
Limitations
Strong sunlight, reflections, extreme light con-
trasts, the use of sunglasses, or if the driver is
not looking straight ahead may make the visual
warning signal in the windshield difficult to see.
For this reason, always activate the audible
warning signal.
Slippery driving conditions increase braking
distance, which can reduce the system's
capacity to avoid a collision. In these condi-tions, the ABS and DSTC systems provide the
best possible braking effect while helping to
maintain stability.
NOTE
The visual warning signal may be temporar-
ily disengaged in the event of high passen-
ger compartment temperature due to strong
sunlight, etc. If this occurs, the audible
warning signal will be used, even if it has
been deactivated in the menu system.
WARNING
•In certain situations, the system cannot
provide warnings or warnings may be
delayed if traffic conditions or other
external factors make it impossible for
the radar sensor or camera to detect a
vehicle ahead.
•Warnings may not be provided if the
distance to the vehicle ahead is short,
or if movements of the steering wheel/
brake pedal are great, such as during
active driving.
•The sensor system has a limited range
for stationary or slow-moving vehicles
and may therefore give delayed or no
warnings if your vehicle’s speed is
above approximately 45 mph
(70 km/h).
•Warnings for stationary or slow-moving
vehicles may not be provided in dark
conditions.
The Collision Warning system uses the same
radar sensors as Adaptive Cruise Control. For
more information on the radar sensor and its
limitations, see page 166.
If no warning is given, or if a warning is delayed,
Auto-brake will also not be provided or will be
delayed.

04 Comfort and driving pleasure
Collision warning with Auto-brake*
04

* Option/accessory, for more information, see Introduction.177
NOTE
If warnings are given too frequently, the
warning distance can be reduced (see
page 175). This causes the system to pro-
vide later warnings, which decreases the
total number of warnings provided.
The camera’s limitationsThe camera is used by Collision Warning with
Auto-brake, Driver Alert Control (see
page 180), and Lane Departure Warning (see
page 183).
NOTE
•To help protect the camera in very hot
conditions, it may be temporarily
switched off for approximately 15
minutes after the engine has been
started.
•Keep the section of the windshield in
front of the camera clean and free of ice,
snow, or condensation.
WARNING
•The camera has the same limitations as
the human eye. In other words, its
“vision is impaired” by adverse weather
conditions such as heavy snowfall,
dense fog, etc. These conditions may
reduce the function of systems that
depend on the camera or cause these
systems to temporarily stop function-
ing.
•Never place any objects, decals, etc.,
on the windshield in front of the camera.
This could reduce or block the camera’s
function, and could cause one or more
of the systems that utilize the camera to
stop functioning.
•Strong sunlight, reflections from the
road surface, ice or snow covering the
road, a dirty road surface, or unclear
lane marker lines may drastically reduce
the camera’s capacity to detect the side
of a lane or another vehicle.
Fault tracing and actions
If the message Windscreen Sensors
blocked is displayed, this means that the cam-
era is obscured and cannot detect vehicles or
road marker lines in front of the vehicle.
This, in turn, means that Collision Warning with
Auto-brake, Lane Departure Warning, and
Driver Alert Control will not have full function-
ality.
The table lists possible causes for this mes-
sage being displayed, and suitable actions.

04 Comfort and driving pleasure
Collision warning with Auto-brake*
04
178* Option/accessory, for more information, see Introduction.
CauseAction
The surface of the windshield in front of the camera is dirty or covered
with ice or snow.Clean or clear the section of the windshield in front of the camera.
Fog, heavy rain or snow is interfering with the function of the camera.No action possible. Heavy precipitation may affect the function of the
camera.
The surface of the windshield is clean but the message remains in the
display.Wait a short time. It may take several minutes for the camera to register
visibility.
The surface between the inside of the windshield and the camera is dirty.Contact an authorized Volvo retailer or service technician to have this
surface cleaned.
Symbols and messages in the display
SymbolMessageDescription
Collis'n warning OFFCollision Warning is switched off. This message is displayed when the engine is started and will dis-
appear after approx. 5 seconds. It can also be erased by pressing the READ button.
Collision warn. Unavaila-
bleCollision Warning cannot be activated. This message is displayed when the driver attempts to activate
the function. It will disappear after approx. 5 seconds or can be erased by pressing the READ button.
Auto braking was acti-
vatedAuto-braking has been active. This message can be erased by pressing the READ button.
Windscreen Sensors
blockedThe camera is temporarily not functioning. This message is displayed if the camera is obstructed by
snow, ice, dirt, etc., on the windshield. Clean the area of the windshield in front of the camera, see
page 177 for more information on the camera’s limitations.

04 Comfort and driving pleasure
Collision warning with Auto-brake*
04
* Option/accessory, for more information, see Introduction.179
SymbolMessageDescription
Radar blocked See man-
ualCollision Warning and Auto-brake are temporarily not functioning. The radar sensor is blocked, for
example by heavy rain or snow that has accumulated in front of the sensor, and cannot detect other
vehicles, see page 166 for more information on the radar sensor’s limitations.
Collision warn. Service
requiredCollision Warning and Auto-brake are partially or completely not functioning.
Contact a trained and qualified Volvo service technician if the message remains in the display.

04 Comfort and driving pleasure
Park assist*
04

* Option/accessory, for more information, see Introduction.185 Introduction
The park assist system is designed to assist
you when driving into parking spaces, garages,
etc. It utilizes four ultrasound sensors located
in one or both bumpers to measure the dis-
tance to a vehicle, object, or a person who may
be close to the front or rear of your vehicle. An
audible signal and symbols in the audio sys-
tem’s display indicate the distance to the
object.
This system is available in the rear bumper
only, or in both the front and rear bumpers.
WARNING
Park Assist is an information system, NOT a
safety system. This system is designed to
be a supplementary aid when parking the
vehicle. It is not, however, intended to
replace the driver's attention and judge-
ment.
Function
Park assist button
The system is activated automatically when the
vehicle is started. The indicator light in the but-
ton in the center console illuminates when the
system is on.
•The front park assist system is active from
the time the engine is started until the vehi-
cle exceeds a speed of approximately
10 mph (15 km/h). It is also active when the
vehicle is backing up.
•Rear park assist is active when the engine
is running and reverse gear has been
selected.
Activating/deactivatingThe system is activated automatically when the
vehicle is started.

Press the Park assist button on the center
console to temporarily deactivate the sys-
tem(s).
> The indicator light in the button will go
out when the system has been deacti-
vated.
Park assist will be automatically reactivated the
next time the engine is started, or if the button
is pressed (the indicator light in the button will
illuminate).
NOTE
•Front park assist is disengaged auto-
matically when the parking brake is
applied.
•If the vehicle is equipped with front and
rear park assist, both systems will be
deactivated by pressing the button.

04 Comfort and driving pleasure
Park assist*
04

* Option/accessory, for more information, see Introduction.187
Front park assist
G021424
The distance monitored in front of the vehicle
is approximately 2.5 ft (0.8 m). The audible sig-
nal comes from the audio system's front
speakers.
It may not be possible to combine auxiliary
headlights and front park assist since these
lights could trigger the system's sensors.
NOTE
Front park assist is deactivated when the
parking brake is applied and or when the
gear selector is in the P position.
Faults in the system
If the information symbol illuminates and Park
assist syst Service required is shown on the
information display, this indicates that the sys-
tem is not functioning properly and has been
disengaged. Consult a trained and qualified
Volvo service technician.
CAUTION
In certain circumstances, the park assist
system may give unexpected warning sig-
nals that can be caused by external sound
sources that use the same ultrasound fre-
quencies as the system. This may include
such things as the horns of other vehicles,
wet tires on asphalt, pneumatic brakes,
motorcycle exhaust pipes, etc. This does
not indicate a fault in the system.
Cleaning the sensors
Location of the front sensors
Location of the rear sensors
The sensors must be cleaned regularly to
ensure that they work properly. Clean them

07 Maintenance and specifications
Vehicle care
07

285
CAUTION
•Avoid waxing or polishing plastic or rub-
ber components
•Polishing chromed strips can wear
away or damage the surface
•Polishes containing abrasive sub-
stances should not be used
Automatic car wash
•We do NOT recommend washing your car
in an automatic wash during the first few
months (because the paint will not have
hardened sufficiently).
•An automatic wash is a simple and quick
way to clean your car, but it is worth
remembering that it may not be as thor-
ough as when you yourself go over the car
with sponge and water. Keeping the under-
body clean is most important, especially in
the winter. Some automatic washers do
not have facilities for washing the under-
body.
CAUTION
•Before driving into an automatic car
wash, turn off the optional rain sensor to
avoid damaging the windshield wipers.
•Make sure that side view mirrors, auxil-
iary lamps, etc, are secure, and that any
antenna(s) are retracted or removed.
Otherwise there is risk of the machine
dislodging them.
•Chromed wheels: Clean chrome-
plated wheels using the same deter-
gents used for the body of the vehicle.
Aggressive wheel-cleaning agents can
permanently stain chrome-plated
wheels.
WARNING
•When the vehicle is driven immediately
after being washed, apply the brakes,
including the parking brake, several
times in order to remove any moisture
from the brake linings.
•Engine cleaning agents should not be
used when the engine is warm. This
constitutes a fire risk.
Exterior lightingCondensation may form temporarily on the
inside of the lenses of exterior lights such as
headlights, fog lights, or taillights. This is nor-mal and the lights are designed to withstand
moisture. Normally, condensation will dissi-
pate after the lights have been on for a short
time.
Polishing and waxing
•Normally, polishing is not required during
the first year after delivery, however, wax-
ing may be beneficial.
•Before applying polish or wax the vehicle
must be washed and dried. Tar spots can
be removed with kerosene or tar remover.
Difficult spots may require a fine rubbing
compound.
•After polishing use liquid or paste wax.
•Several commercially available products
contain both polish and wax.
•Waxing alone does not substitute for pol-
ishing a dull surface.
•A wide range of polymer-based waxes can
be purchased today. These waxes are easy
to use and produce a long-lasting, high-
gloss finish that protects the bodywork
against oxidation, road dirt and fading.
•Do not polish or wax your vehicle in direct
sunlight (the surface of the vehicle should
not be warmer than 113 °F (45 °C).