Page 189 of 289

Driving and operating187Brake preparation system
When approaching a vehicle ahead
so quickly that a collision is likely, the brake preparation system slightlypressurises 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 the imminent 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
acceptable operation, the vehicle
does not need service. Firmly apply
the accelerator pedal to override the
automatic braking.
Settings
Settings can be changed in the
vehicle personalisation menu in the
Info-Display.
Select the relevant setting in
Settings in the Info-Display.
Vehicle personalisation 3 125.
Fault
In the event of a system service
requirement, a message is displayed
in the Driver Information Centre.
Page 215 of 289

Vehicle care213Vehicle careGeneral Information...................214
Accessories and vehicle modifications .......................... 214
Vehicle storage ........................214
End-of-life vehicle recovery .....215
Vehicle checks ........................... 215
Performing work ......................215
Bonnet ..................................... 215
Engine oil ................................. 216
Engine coolant ......................... 217
Power steering fluid .................218
Washer fluid ............................ 218
Brakes ..................................... 219
Brake fluid ............................... 219
Vehicle battery ......................... 219
Diesel fuel system bleeding .....221
Wiper blade replacement ........221
Bulb replacement .......................222
Halogen headlights ..................222
LED headlights ........................ 224
Fog lights ................................. 224
Tail lights ................................. 225
Side turn signal lights ..............227
Number plate light ...................228Interior lights ............................ 228
Instrument panel illumination ...229
Electrical system ........................229
Fuses ....................................... 229
Engine compartment fuse box . 230
Instrument panel fuse box .......232
Load compartment fuse box ....233
Vehicle tools .............................. 235
Tools ........................................ 235
Wheels and tyres .......................236
Winter tyres ............................. 236
Tyre designations ....................236
Tyre pressure .......................... 236
Tyre pressure monitoring system .................................... 238
Tread depth ............................. 241
Changing tyre and wheel size . 241
Wheel covers ........................... 241
Tyre chains .............................. 242
Tyre repair kit .......................... 242
Wheel changing .......................245
Spare wheel ............................ 247
Jump starting ............................. 251
Towing ....................................... 252
Towing the vehicle ...................252
Towing another vehicle ...........253Appearance care .......................254
Exterior care ............................ 254
Interior care ............................. 256
Page 221 of 289

Vehicle care219Caution
Only washer fluid with a sufficient
antifreeze concentration provides
protection at low temperatures or
a sudden drop in temperature.
Brakes
In the event of minimum thickness of
the 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 fluid
9 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.
If fluid level is below MIN seek the
assistance of a workshop.
Brake and clutch fluid 3 259.
Vehicle 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.
Laying up the vehicle for more than
four weeks can lead to battery
discharge. Disconnect the clamp from the negative terminal of the vehicle
battery.
Ensure the ignition is switched off
before connecting or disconnecting
the vehicle battery.
Vehicle battery discharge protection
3 141.
Page 284 of 289

282IndexAAccessories and vehicle modifications .......................... 214
Active Emergency Braking .........186
Active head restraints ...................37
Adaptive cruise control .......117, 176
AdBlue ........................ 115, 159, 259
Adjustable air vents ...................148
Airbag and belt tensioners .........111
Airbag deactivation ..............58, 112
Airbag label................................... 54
Airbag system .............................. 54
Air conditioning regular operation ................................ 149
Air conditioning system .............. 143
Air intake .................................... 149
Air vents...................................... 148
Antilock brake system ................ 166
Antilock brake system (ABS) .....113
Anti-theft alarm system ................26
Anti-theft locking system .............. 26
Appearance care ........................254
Armrest ......................................... 42
Armrest storage ........................... 69
Ashtrays ..................................... 103
Automatic anti-dazzle ..................30
Automatic light control ...............133
Automatic locking ........................24
Automatic transmission .............162Autostop..................................... 154
Auxiliary heater ........................... 148
B Battery discharge protection ......141
Battery voltage ........................... 124
Bicycle rack .................................. 70
BlueInjection ............................... 159
Bonnet ....................................... 215
Brake and clutch fluid .................259
Brake and clutch system ...........112
Brake assist ............................... 168
Brake fluid .................................. 219 Brakes ............................... 166, 219
Breakdown.................................. 252
Bulb replacement ....................... 222
C Capacities .................................. 272
Cargo management system ........88
Car Pass ...................................... 21
Catalytic converter .....................158
Central locking system ................22
Centre console lighting ..............140
Centre console storage ...............69
Changing tyre and wheel size ...241
Charging system ........................ 112
Child locks ................................... 25
Child restraint installation locations ................................... 63
Child restraints.............................. 60