Page 195 of 329
Driving and operating193
Press button V; the current setting is
shown on the Driver Information
Centre. Press button V again to
change the alert sensitivity.Alerting the driver
When approaching another vehicle
too rapidly, the collision alert warning page will be indicated in the Driver
Information Centre. Simultaneously a
warning chime sounds. Depress the
brake pedal, if it is required by the situation.
Deactivation
The system can be deactivated.
Press button V repeatedly until the
following message appears in the
Driver Information Centre.
General information for both
variants of forward collision alert
9 Warning
Forward collision alert is just a
warning system and does not
apply the brakes. When
approaching a vehicle ahead too
rapidly, it may not provide you
enough time to avoid a collision.
The driver accepts full
responsibility for the appropriate
following distance based on traffic, weather and visibility conditions.
Page 196 of 329

194Driving and operatingThe complete attention of the
driver is always required while
driving. The driver must always be ready to take action and apply the
brakes.
System limitations
The system is designed to warn only for vehicles, but may react also to
other metallic objects.
In the following cases, forward
collision alert may not detect a vehicle
ahead or sensor performance is
limited:
■ on winding roads,
■ when weather limits visibility, e.g. fog, rain, or snow,
■ when the sensor is blocked by snow, ice, slush, mud, dirt, or
windscreen damage.
Following distance
indication The following distance indication
displays the distance to a preceding
moving vehicle. The system uses,
depending on the vehicle equipment,
either the radar behind the radiator
grille or the front camera in the
windscreen to detect the distance of
a vehicle directly ahead in your lane.
It is active at speeds above 25 mph.
When a preceding vehicle is detected
ahead, the distance is indicated in
seconds, displayed on a page in the
Driver Information Centre 3 119.
Press the MENU button on the turn
signal lever to select Vehicle
Information Menu X and turn the
adjuster wheel to choose following distance indication page.The minimum indicated distance is
0.5 s.
If there is no vehicle ahead or the vehicle ahead is out of range, two
dashes will be displayed: -.- s.
Active Emergency Braking
Active emergency braking can help to reduce the damage from crashes with vehicles and obstacles directly
ahead, when a collision can no longer be avoided either by manual braking
or by steering. Before the active
emergency braking applies, the driver
is warned by the forward collision
alert 3 191.
The feature uses various inputs (e.g.
radar sensor, brake pressure, vehicle speed) to calculate the probability ofa frontal collision.
Active emergency braking operates automatically above walking speed,
provided that Auto collision
preparation setting is not deactivated
in the vehicle personalisation menu
3 132.
Page 197 of 329

Driving and operating195
The system includes:■ Brake preparation system
■ Emergency automatic braking
■ Forward looking brake assist9 Warning
This system is not intended to
replace the driver responsibility of driving the vehicle and looking
ahead. Its function is limited to
supplemental use only. The driver shall continue to apply the brake
pedal as the driving situation
dictates.
Brake preparation system
When approaching a vehicle ahead
so quickly that a collision is likely, the brake preparation system slightly
pressurises the brakes. This reduces
the response time, when a manual or automatic braking is requested.
The brake system is prepared so that braking can occur more rapidly.
Emergency automatic braking
After the brake preparation and just
before the imminent collision, this
function automatically applies limited
braking to reduce the impact speed of
the collision.
Forward looking brake assist
In addition to brake preparation
system and emergency automatic
braking, the forward looking brake
assist function makes the brake assist more sensitive. In this way,
depressing the brake pedal slightly
results immediately in a strong
braking. This function helps the driver brake quicker and stronger before theimminent collision.9 Warning
Active emergency braking is not
designed to apply strong
autonomous braking or to avoid automatically a collision. It is
designed to reduce the vehicle
speed before collision. It may not
react on stopped vehicles,
pedestrians or animals. After a
sudden lane change, the system
needs a certain time to detect the
next preceding vehicle.
The complete attention of the
driver is always required while
driving. The driver shall always be ready to take action and apply the brakes and steer to avoid
collisions. The system is designed
to work with all occupants wearing their seat belts.
System limitations
The active emergency braking has
limited or no function during rain,
snow or heavy dirt, as the radar
sensor can be covered by a water
film, dust, ice or snow. In case of
sensor blockage, clean the sensor
cover.
In some seldom cases the active
emergency braking system may
provide a short automatic braking in
situations that seem to be
unnecessary, for instance due to
traffic signs in a curve or due to
vehicles in another lane. This is
Page 229 of 329

Vehicle care227BrakesIn the event of minimum thickness ofthe brake lining, a squealing noise
sounds during braking.
Continued driving is possible but
have the brake lining replaced as
soon as possible.
Once new brake linings are installed,
do not brake unnecessarily hard for
the first few journeys.
Brake fluid9 Warning
Brake fluid is poisonous and
corrosive. Avoid contact with eyes, skin, fabrics and painted surfaces.
The brake fluid level must be betweenthe MIN and MAX marks.
When topping up, ensure maximum cleanliness as contamination of the
brake fluid can lead to brake system
malfunctions. Have the cause of the
loss of brake fluid remedied by a
workshop.
Only use high-performance brake
fluid approved for the vehicle. Brake
and clutch fluid 3 283.
Vehicle battery
Vehicles without stop-start system
will be equipped with a lead acid
battery. Vehicles with stop-start
system will be equipped with an
AGM battery which is not a lead acid
battery.
The vehicle battery is maintenance-
free provided that the driving profile
allows sufficient charging of the
battery. Short-distance-driving and
frequent engine starts can discharge
the battery. Avoid the use of
unnecessary electrical consumers.
Batteries do not belong in household
waste. They must be disposed of at
an appropriate recycling collection
point.
Page 324 of 329

322IndexAAccessories and vehicle modifications .......................... 222
Active Emergency Braking .........194
Active head restraints ..................39
Adaptive cruise control .......119, 184
Adaptive forward lighting ..........
................................ 118, 143, 234
Adjustable air vents ...................160
Advanced parking assist ............199
Airbag and belt tensioners .........113
Airbag deactivation ..............53, 113
Airbag system .............................. 50
Air conditioning regular operation ................................ 161
Air conditioning system .............. 154
Air intake .................................... 161
Air vents...................................... 160
Antilock brake system ................ 173
Antilock brake system (ABS) .....115
Anti-theft alarm system ................29
Anti-theft locking system .............. 28
Appearance care ........................278
Armrest .................................. 46, 47
Armrest storage ........................... 62
Ashtrays ..................................... 107
Automatic anti-dazzle ..................33
Automatic light control ...............141
Automatic locking ........................25Automatic transmission .............169
Auxiliary heater ........................... 160
B Battery discharge protection ......151
Battery voltage ........................... 129
Belts.............................................. 47 Bicycle rack .................................. 64
Bonnet ....................................... 224
Brake and clutch fluid .................283
Brake and clutch system ...........114
Brake assist ............................... 176
Brake fluid .................................. 227
Brakes ............................... 173, 227
Breakdown.................................. 276
Bulb replacement ....................... 230
C Capacities .................................. 306
Cargo management system ........91
Car Pass ...................................... 21
Catalytic converter .....................169
Central locking system ................23
Centre console lighting ..............150
Centre console storage ...............63
Changing tyre and wheel size ...262
Charging system ........................ 114
Child locks ................................... 25
Child restraint installation locations ................................... 56