Page 25 of 273

Keys, doors and windows23
1. Remove the back cover from theremote control.
2. Extract the flat battery from its location.
3. Replace battery with a battery of the same type. Pay attention to
the installation position.
4. Clip the back cover in place.
Fault
If the central locking system cannot
be operated with the radio remote
control, the cause may be one of the
following:
● Fault in radio remote control.● Electronic key is out of reception range.
● The battery voltage is too low.
● Overload of the central locking system by operating at frequentintervals, the power supply is
interrupted for a short time.
● Interference from higher-power radio waves from other sources.
Manual unlocking 3 24.Electronic key system
Enables a keyless operation of the
following functions:
● central locking system 3 24
● power tailgate 3 30
● ignition switching on and starting the engine 3 139
The electronic key simply needs to be on the driver's person.
Additionally, the electronic key
includes the functionality of the radio
remote control 3 22.
Handle with care, protect from
moisture and high temperatures and
avoid unnecessary operation.
Page 26 of 273

24Keys, doors and windowsReplacing battery in electronic
key
Replace the battery as soon as the
system no longer operates properly
or the range is reduced. The need for battery replacement is indicated by a
message in the Driver Information
Centre 3 105.
Batteries do not belong in household
waste. They must be disposed of at
an appropriate recycling collection
point.
1. Remove the cover.
2. Extract the flat battery from its location.
3. Replace battery with a battery of the same type. Pay attention to
the installation position.
4. Clip the cover in place.
Fault
If the central locking cannot be
operated or the engine cannot be
started, the cause may be one of the
following:
● Fault in electronic key.
● Electronic key is out of reception range.
● The battery voltage is too low.
● Overload of the central locking system by operating at frequent
intervals, the power supply is
interrupted for a short time.
● Interference from higher-power radio waves from other sources.
To rectify the cause of the fault,
change the position of the electronic
key.
Manual unlocking 3 24.
Central locking system Unlocks and locks doors, load
compartment and fuel filler flap.
A pull on an interior door handle
unlocks the respective door. Pulling
the handle once more opens the door.
Note
In the event of an accident in which
airbags or belt pretensioners are
deployed, the vehicle is
automatically unlocked.
Note
A short time after unlocking with the
remote control the doors are locked
automatically if no door has been
Page 268 of 273

266IndexAAccessories and vehicle modifications .......................... 202
Active emergency braking ..100, 171
Adaptive cruise control .......100, 163
AdBlue .................................. 98, 145
Adjustable air vents ...................132
Advanced parking assist ............179
Airbag and belt tensioners ...........94
Airbag deactivation ................60, 95
Airbag label................................... 55 Airbag system .............................. 55
Air conditioning regular operation ................................ 134
Air conditioning system .............. 125
Air intake .................................... 133
Air vents...................................... 132
Antilock brake system ................ 152
Antilock brake system (ABS) .......97
Anti-theft alarm system ................35
Anti-theft locking system .............. 35
Appearance care ........................236
Armrest ................................... 51, 52
Ashtrays ....................................... 88 Automatic anti-dazzle ..................39
Automatic light control ...............115
Automatic locking ........................28
Automatic transmission .............148
Autostop ............................... 99, 140
Auxiliary heater ........................... 132B
Battery discharge protection ......123
Battery voltage ........................... 105
BlueInjection ............................... 145
Bonnet ....................................... 204
Brake and clutch fluid .................242
Brake and clutch system .............96
Brake assist ............................... 154
Brake fluid .................................. 207
Brakes ............................... 152, 207
Breakdown.................................. 234
Bulb replacement ....................... 210
C Capacities .................................. 253
Catalytic converter .....................144
Central locking system ................24
Centre console lighting ..............122
Centre console storage ...............70
Changing tyre and wheel size ...224
Charging system .......................... 95
Child locks ................................... 29
Child restraint installation locations ................................... 65
Child restraints.............................. 62
Child restraint systems ................62
Cigarette lighter ........................... 87
Climate control ............................. 16
Climate control systems .............124
Clock............................................. 84