2012 VOLVO XC70 brake sensor

04 Comfort and driving pleasure
Distance Alert*
04
* Option/accessory, for more information, see Introduction.165 Symbols and messages in the display
SymbolMessageDescription
-Time interval while it is being set.
-Time interval after it has been set.
Radar blocked See manualDistance Alert has been temporarily disconnected because the radar is obstructed in some way and
cannot detect other vehicles. See page 158 for information on the radar sensor’s limitations.
Collision warn. Service
requiredDistance Alert or Collision Warning with Full Auto-brake and Pedestrian Detection is not functioning
properly. Contact a trained and qualified Volvo service technician.

04 Comfort and driving pleasure
City Safety™
04

167
driver is always responsible for main-
taining a safe distance to the vehicle
ahead.
Function
Location of the laser sensor in the windshield2
City Safety™ monitors traffic ahead of you
using a laser sensor mounted in the upper sec-
tion of the windshield. If a collision is imminent,
City Safety™ will automatically apply the
brakes, which may feel like hard braking.
If the difference in speed between your vehicle
and the vehicle ahead is more than approxi-
mately 9 mph (15 km/h), City Safety™ alone
cannot prevent a collision from taking place.The driver must apply the brakes to help avoid
a collision or reduce its effect.
When the function activates and applies the
brakes, a message will appear in the informa-
tion display to indicate that the system is/has
been active.
NOTE
•When City Safety™ applies the brakes,
the brake lights will illuminate.
•In cases where City Safety™ has stop-
ped the vehicle, the system will then
release the brakes. The driver must
apply the brakes to keep the vehicle at
a standstill.
Using City Safety™
NOTE
The City Safety™ function is activated auto-
matically each time the engine has been
switched off and restarted.
On and OffIn certain situations, it may be desirable to
switch City Safety™ off, such as when drivingin close quarters where leaves, branches, etc.
may obscure the hood and windshield.
When the engine is running, City Safety™ can
be switched off as follows:
Press My Car in the center console control
panel and go to Settings
Car settings
Driver support systemsCity Safety.
Select
Off.
If the engine is switched off, City Safety™ will
reactivate when the engine is restarted.
WARNING
The laser sensor emits light when the igni-
tion is in mode II or higher, even if City
Safety™ has been switched off.
To switch City Safety™ on again:
•Follow the same procedure as for switch-
ing City Safety™ off but select ON.
2The illustration is schematic; details will vary, depending on the model

04 Comfort and driving pleasure
City Safety™
04
170
Symbols and messages in the display
When City Safety™ automatically applies the
brakes, one or more of the symbols in the maininstrument panel may illuminate and its asso-
ciated message will be displayed.
A text message can be erased by pressing
briefly on the READ button on the turn signal
lever.
SymbolMessageMeaning/action required
Auto braking by City SafetyCity Safety™ is applying/has applied the brakes automatically.
Windscreen Sensors
blockedThe laser sensor is temporarily not functioning due to an obstruction.
•Remove the obstruction and/or clean the windshield in front of the sensor(s).
For more information on the sensor’s limitations, see page 168.
City Safety Service requiredCity Safety™ is not functioning.
•If this message remains in the display, have the system checked by a trained and qualified Volvo
service technician.

04 Comfort and driving pleasure
Collision warning with Full Auto-brake and Pedestrian Detection*
04
172* Option/accessory, for more information, see Introduction.
WARNING
•Collision Warning will not provide a
warning or brake the vehicle for pedes-
trians in darkness or in tunnels, even if
there is street lighting in the area.
•The auto-brake function can help pre-
vent a collision or 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
Function overview
Visual warning signal, collision risk
Radar sensor
Camera
Collision WarningThe radar sensor and the camera work
together to detect a pedestrian, stationary
vehicles and vehicles that are moving in the
same direction as your vehicle. If there is a risk
of collision with a vehicle or a pedestrian, the
driver is alerted by a flashing red warning light
and an audible warning signal. Collision warn-
ing is active at speeds above 3 mph (4 km/h).
Brake SupportIf the risk of collision continues to increase after
the collision warning has been given, Brake
Support is activated. Brake Support prepares
the brake system to react quickly, and the
brakes are applied slightly. This may be expe-
rienced as a light tug.
If the brakes are applied quickly, full braking
effect will be provided. Brake Support also
increases brake force if the system determines
that the driver has not applied adequate pres-
sure on the brake pedal.
Auto-brakeIf a collision is imminent and the driver has not
applied the brakes or begun to steer around the
vehicle or pedestrian, the auto-brake function
is activated without the driver pressing the
brake pedal. Full brake force is applied to help
reduce the vehicle’s speed when the collision
occurs or limited brake force is applied if this
is sufficient to avoid the collision.
NOTE
The auto-brake and brake support functions
are always on and cannot be turned off.

04 Comfort and driving pleasure
Collision warning with Full Auto-brake and Pedestrian Detection*
04
174* Option/accessory, for more information, see Introduction.
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
pedestrian or 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 pedestrians and provides warnings
and braking effect most effectively at
speeds up to 30 mph (50 km/h). For sta-
tionary or slow-moving vehicles, the
system functions best if your vehicle’s
speed is below approximately 45 mph
(70 km/h).
•Warnings for stationary or slow-moving
vehicles may not be provided in dark
conditions or in poor visibility.
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 158.
NOTE
If warnings are given too frequently, the
warning distance can be reduced (see
page 173). This causes the system to pro-
vide later warnings, which decreases the
total number of warnings provided.
WARNING
•The system is not activated at speeds
under approx. 2 mph (4 km/h). There-
fore, it will not brake your vehicle if you
approach a vehicle ahead at very low
speed, such as when parking.
•The driver's actions always have high-
est priority and override the Collision
Warning system. This means that the
system will not intervene in situations
where the driver is actively steering,
braking or pressing the accelerator
pedal, even if a collision is imminent.
•When Auto-brake has prevented a col-
lision with a stationary object, your vehi-
cle will remain at a standstill for approx.
1.5 seconds. If your vehicle has been
braked for a moving vehicle ahead, your
vehicle's speed will be reduced to the
same speed as that vehicle's.

04 Comfort and driving pleasure
Collision warning with Full Auto-brake and Pedestrian Detection*
04
176* Option/accessory, for more information, see Introduction.
body and the person must be at least
32 in. (80 cm) tall.
•The system cannot detect a pedestrian
carrying a large object.
•The camera's capacity to see a pedestrian
at dawn or dusk is limited, much as it is for
the human eye.
•The camera's function is deactivated and
will not detect a pedestrian in darkness or
in tunnels, even if there is street lighting in
the area.
WARNING
•Collision Warning with Full Auto-brake
and Pedestrian Detection is designed to
be a supplementary driving aid. It is not,
however, intended to replace the driv-
er's attention and judgement. The driver
is always responsible for operating the
vehicle in a safe manner.
•The system cannot detect all pedes-
trians in all situations, such as in dark-
ness/at night and cannot detect parti-
ally hidden pedestrians, people who are
less than approx. 32 in. (80 cm) tall, or
people wearing clothing that obscures
the contours of their bodies.
Fault tracing and actions
If the message Windscreen Sensors
blocked is displayed, this means that the cam-
era is obscured and cannot detect pedestrians,
vehicles or road marker lines in front of the
vehicle.
This, in turn, means that Collision Warning with
Full Auto-brake and Pedestrian Detection,
Lane Departure Warning, and Driver Alert Con-
trol will not have full functionality.
The table lists possible causes for this mes-
sage being displayed, and suitable actions.

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

* Option/accessory, for more information, see Introduction.177
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 175 for more information on the camera’s limitations.

04 Comfort and driving pleasure
Collision warning with Full Auto-brake and Pedestrian Detection*
04
178* Option/accessory, for more information, see Introduction.
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 158 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.