2012 MERCEDES-BENZ E-Class SEDAN key battery

X To unlock the vehicle: touch the inner
surface of the door handle.XTo lock the vehicle: touch sensor
surface :.XConvenience closing feature: touch
recessed sensor surface ; for an
extended period ( Y page 92).
If you pull on the handle of the trunk lid/
tailgate, only the trunk/cargo compartment
of the vehicle is unlocked.
Changing the settings of the locking
system
You can change the setting of the locking
system in such a way that only the driver's
door and the fuel filler flap are unlocked. This
is useful if you frequently travel on your own.
XTo change the setting: press and hold
down the % and & buttons
simultaneously for approximately six
seconds until the battery check lamp
( Y page 78) flashes twice.
i
If the setting of the locking system is
changed within the signal range of the
vehicle, pressing the & or % button
locks or unlocks the vehicle.
The SmartKey now functions as follows:
XTo unlock the driver's door: press the
% button once.XTo unlock centrally: press the %
button twice.XTo lock centrally: press the & button.The KEYLESS-GO function is changed as
follows:XTo unlock the driver's door: touch the
inner surface of the door handle on the
driver's door.XTo unlock centrally: touch the inner
surface of the door handle on the front-
passenger door or the rear door.XTo lock centrally: touch the outer sensor
surface on one of the door handles.
Restoring the factory settings
XPress the % and & buttons
simultaneously for approximately six
seconds until the battery check lamp
flashes twice.
Mechanical key
General notes
If the vehicle can no longer be locked or
unlocked with the SmartKey, use the
mechanical key.
If you use the mechanical key to unlock and
open the driver's door or the trunk lid/
tailgate, the anti-theft alarm system will be
triggered ( Y page 72).
There are several ways to turn off the alarm:
XTo turn the alarm off with the
SmartKey: press the % or & button
on the SmartKey.
or
XInsert the SmartKey into the ignition lock.
or
XTo deactivate the alarm with KEYLESS-
GO: press the Start/Stop button in the
ignition lock. The SmartKey must be in the
vehicle.
or
XLock or unlock the vehicle using KEYLESS-
GO. The SmartKey must be outside the
vehicle.SmartKey77Opening/closingZ

If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked
automatically.XTo unlock the fuel filler flap: insert the
SmartKey in the ignition lock.
Removing the mechanical key
XPush release catch : in the direction of
the arrow and at the same time, remove
mechanical key ; from the SmartKey.
SmartKey battery
Important safety notes
Have the batteries changed at a qualified
specialist workshop.
GWARNING
Batteries contain toxic substances.
Swallowing batteries can lead to serious
health issues or death.
Keep batteries out of the reach of children.
Seek medical attention immediately if a
battery is swallowed.
GWARNING
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. Observe
government disposal guidelines. California
residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm .
Checking the batteryXPress the & or % button.
The battery is working properly if battery
check lamp : lights up briefly
If battery check lamp : does not light up
briefly during the test, the battery is
discharged.
XChanging the battery ( Y page 78)
i
You can obtain the battery at a qualified
specialist workshop.
i If the SmartKey battery is checked within
the signal reception range of the vehicle,
pressing the & or % button locks or
unlocks the vehicle.
Changing the battery
You require a CR 2025 3 V cell battery.
XTake the mechanical key out of the
SmartKey ( Y page 77).XPress mechanical key ; into the opening
in the SmartKey in the direction of the78SmartKeyOpening/closing

arrow until battery tray cover : opens.
When doing so, do not hold cover : shut.XRemove battery tray cover :.XRepeatedly tap the SmartKey against your
palm until battery = falls out.XInsert the new battery with the positive
terminal facing upwards. Use a lint-free
cloth to do so.XMake sure that the surface of the battery is
free from lint, grease and all other forms of
contamination.XInsert the front tabs of battery tray
cover : and then press to close it.XInsert the mechanical key into the
SmartKey.XCheck the function of all SmartKey buttons
on the vehicle.SmartKey79Opening/closingZ

Problems with the SmartKeyProblemPossible causes/consequences and M SolutionsYou cannot lock or
unlock the vehicle
using the SmartKey.The SmartKey battery is discharged or nearly discharged.XTry again to lock/unlock the vehicle using the remote control
function of the SmartKey. Point the tip of the SmartKey at the
driver's door handle from close range and press the %/
& button.
If this does not work:
XCheck the SmartKey battery ( Y page 78) and replace it if
necessary ( Y page 78).XLock ( Y page 83) or unlock ( Y page 84) the vehicle using
the mechanical key.The SmartKey is faulty.XLock ( Y page 83) or unlock ( Y page 84) the vehicle using
the mechanical key.XHave the SmartKey checked at a qualified specialist workshop.You can no longer lock
or unlock the vehicle
using KEYLESS-GO.KEYLESS-GO is in standby mode because the vehicle has not been
unlocked for an extended period.XPull the door handle and then turn the SmartKey to position 2
in the ignition lock.There is interference from a powerful source of radio waves.XLock/unlock the vehicle using the remote control function of
the SmartKey. Point the tip of the SmartKey at the driver's door
handle from close range and press the %/& button.There is a malfunction with KEYLESS-GO.XLock/unlock the vehicle using the remote control function of
the SmartKey. Point the tip of the SmartKey at the driver's door
handle from close range and press the %/& button.XHave KEYLESS-GO checked at a qualified specialist workshop.
If this does not work:
XCheck the SmartKey battery ( Y page 78) and replace it if
necessary ( Y page 78).XLock ( Y page 83) or unlock ( Y page 84) the vehicle using
the mechanical key.You have lost a
SmartKey.XHave the SmartKey deactivated at a qualified specialist
workshop.XReport the loss immediately to the vehicle insurers.XIf necessary, have the locks changed as well.80SmartKeyOpening/closing

ProblemPossible causes/consequences and M SolutionsYou have lost the
mechanical key.XReport the loss immediately to the vehicle insurers.XIf necessary, have the locks changed as well.The engine cannot be
started using the
SmartKey.The on-board voltage is too low.XSwitch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
XCheck the starter battery and charge it if necessary
( Y page 335).
or
XJump-start the vehicle ( Y page 338).
or
XConsult a qualified specialist workshop.The engine cannot be
started using the
SmartKey.The steering lock is mechanically blocked 3
.XRemove the SmartKey and reinsert it into the ignition lock. While
doing this, turn the steering wheel in both directions.The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle.A door is open. Therefore, the SmartKey cannot be detected as
easily.XClose the door and try to start the vehicle again.There is interference from a powerful source of radio waves.XStart your vehicle with the SmartKey in the ignition lock.3 Not on vehicles with DIRECT SELECT lever.SmartKey81Opening/closingZ

XInsert the mechanical key into the trunk lid
lock as far as the stop.XTurn the mechanical key clockwise from
position 1 to position 2.XRemove the mechanical key.XInsert the mechanical key into the
SmartKey.
Unlocking the trunk (Sedan)
! The trunk lid swings upwards when
opened. Therefore, make sure that there is
sufficient clearance above the trunk lid.
If the trunk cannot be unlocked with the
SmartKey or KEYLESS-GO, use the
mechanical key.
If you use the mechanical key to unlock and
open the trunk lid, the anti-theft alarm system
will be triggered ( Y page 72).
XTake the mechanical key out of the
SmartKey ( Y page 77).XInsert the mechanical key into the trunk lid
lock as far as the stop.XTurn the mechanical key counter-clockwise
from position 1 as far as it will go to
position 2.
The trunk is unlocked.XTurn the mechanical key back to position
1 and remove it.XInsert the mechanical key into the
SmartKey.Trunk emergency release (Sedan)
You can open the trunk lid from inside the
vehicle with the emergency release button.XBriefly press emergency release
button :.
The trunk lid unlocks and opens.
The trunk lid can be unlocked and opened
with the trunk lid emergency release when
the vehicle is stationary or while driving.
Trunk lid emergency release light:
R emergency release button : flashes for
30 minutes after the trunk lid is opened.
R emergency release button : flashes for
60 minutes after the trunk lid is closed.
The trunk lid emergency release does not
open the trunk lid if the battery is
disconnected or discharged.
Tailgate emergency release (Wagon)
If the tailgate can no longer be opened from
outside the vehicle, use the emergency
release on inside of the tailgate.
On vehicles with a folding bench seat you can
open the tailgate from inside the vehicle using
the handle.
XTake the mechanical key out of the
SmartKey ( Y page 77).
To open the tailgate completely, a minimum
clearance of 6.36 ft (1.94 m) above the
ground is necessary.
Trunk/cargo compartment89Opening/closingZ

Rear seats8
The system automatically switches down
from level 3 to level 2 after about eight
minutes (driver's seat and front-passenger
seat) or five minutes (rear seats).
The system automatically switches down
from level 2 to level 1 after approximately ten
minutes.
The system automatically switches off
approximately 20 minutes after it is set to
level 1.
XMake sure that the SmartKey is in position
2 in the ignition lock.XTo switch on: press button : repeatedly
until the desired heating level is set.XTo switch off: press button : repeatedly
until all the indicator lamps go out.
Problems with the seat heating
The seat heating has switched off
prematurely or cannot be switched on. The
vehicle's electrical system voltage is too low
because too many electrical consumers are
switched on.
XSwitch off electrical consumers which you
do not need, such as the rear window
defroster or interior lighting.Switching the seat ventilation on/off
Switching on/off
The three blue indicator lamps in the buttons
indicate the ventilation level you have
selected.
i If the battery voltage is too low, the seat
ventilation may switch off.
XMake sure that the SmartKey is in position
2 in the ignition lock.XTo switch on: press button : repeatedly
until the desired ventilation level is set.
i You can open the side windows and the
sliding sunroof using the "Convenience
opening" feature ( Y page 91). The seat
ventilation of the driver's seat
automatically switches to the highest level.
XTo switch off: press button : repeatedly
until all the indicator lamps go out.
Problems with the seat ventilation
The seat ventilation has switched off
prematurely or cannot be switched on. The
vehicle's electrical system voltage is too low
because too many electrical consumers are
switched on.
XSwitch off electrical consumers which you
do not need, such as the rear window
defroster or interior lighting.8 For Canada only.106SeatsSeats, steering wheel and mirrors

Steering wheel
Important safety notes
GWARNING
Do not adjust the steering wheel while driving.
Adjusting the steering wheel while driving
could cause the driver to lose control of the
vehicle.
The electrical steering wheel adjustment
feature can be operated at any time.
Therefore, do not leave children unattended
in the vehicle, or with access to an unlocked
vehicle. A child's unsupervised access to a
vehicle could result in an accident and/or
serious personal injury.
Adjusting the steering wheel
:To adjust the steering wheel height;To adjust the steering wheel position
(fore-and-aft adjustment)
i Other topics:
R EASY-ENTRY/EXIT feature
( Y page 108)
R storing settings ( Y page 111)
Steering wheel heating
Switching on/off
The steering-wheel heating heats the leather
areas of the steering wheel.
XMake sure that the SmartKey is in position
2 in the ignition lock.XTo switch on/off: turn the lever in the
direction of arrow : or ;.
Indicator lamp = lights up or goes out.
i The steering wheel heating may switch off
temporarily if:
R the temperature of the vehicle interior is
above 86 ‡ (30 †).
R the temperature of the steering wheel is
above 95 ‡ (35 †).
Indicator lamp = remains on.
Vehicles without KEYLESS-GO: when you
remove the SmartKey from the ignition lock,
the steering wheel heating is deactivated.
Vehicles with KEYLESS-GO: when you switch
off the ignition and open the driver's door, the
steering wheel heating is deactivated.
Problems with the steering wheel
heating
If steering wheel heating indicator lamp = is
flashing, the steering wheel heating has
switched off automatically. The vehicle's
electrical system voltage is too low because
too many electrical consumers are switched
on.
XSwitch off electrical consumers which you
do not need, such as the rear window
defroster or interior lighting.
Once the battery is sufficiently charged, the
steering wheel heating will switch back on
automatically.Steering wheel107Seats, steering wheel and mirrorsZ