change key battery MERCEDES-BENZ C-Class 2011 W204 Owner's Manual

BatteryCharging ........................................ 261
Checking (SmartKey) .......................74
Display message ............................ 196
Important safety guidelines
(SmartKey) ....................................... 74
Jump-starting ................................. 262
Replacing (SmartKey) ......................74
Safety notes .................................. 259
Belt
see Seat belts
Brake fluid
Notes ............................................. 309
Brake fluid level ................................ 242
Brake lamp (display message) ......... 192
Brakes ABS .................................................. 62
BAS .................................................. 62
Brake fluid (notes) .........................309
Display message ............................ 190
High-performance brake system ....153
Important safety notes ..................151
Maintenance .................................. 152
Parking brake ................................ 149
Warning lamp ................................. 203
Breakdown
see Accident (notes)
see Flat tire
Bulbs
Backup lamp .................................. 115
Brake lamp .................................... 115
High-beam headlamps ...................113
Low-beam headlamps ....................113
Overview ........................................ 112
Parking lamps ................................ 114
Rear fog lamp ................................ 115
Replacing ....................................... 114
Side marker lamp .......................... 115
Standing lamps (front) ...................114
Tail lamp ........................................ 115
Turn signal lamp ............................ 115
Turn signals (front) ......................... 114C
CAC (Customer Assistance Center) .........21
California
Important notice for retail
customers and lessees ....................19
Calling up a malfunction
see Display messages
Capacities
see Technical data
Care
Carpets .......................................... 249
Car wash ........................................ 244
Display ........................................... 247
Gear or selector lever ....................248
Headlamps ..................................... 246
Matte finish ................................... 245
Notes ............................................. 243
Paint .............................................. 245
Plastic trim .................................... 247
Power washer ................................ 244
Rear view camera .......................... 247
Roof lining ...................................... 249
Seat belt ........................................ 249
Seat covers .................................... 248
Sensors ......................................... 247
Steering wheel ............................... 248
Tail pipes ....................................... 247
Trim strips ..................................... 248
Washing by hand ........................... 244
Wheels ........................................... 245
Windows ........................................ 246
Wiper blades .................................. 246
Wooden trim .................................. 248
Cargo tie down rings ......................... 219
CD player/CD changer (on-board
computer) .......................................... 175
Center console ..................................... 29
Central locking Automatic locking (on-board
computer) ...................................... 181
SmartKey ......................................... 70
Changing bulbs
Headlamps ..................................... 111
Changing gears .................................. 139
Changing the programming SmartKey ......................................... 73Index5BA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 5

iIf the vehicle has been parked for a long
time, the sensor surfaces are deactivated
automatically.
Pull the door handle to unlock the door and
turn on the ignition once to activate the
sensor surfaces again.
Changing the settings of the locking
system
You can change the settings 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 the %
and & buttons simultaneously for
approximately six seconds until the battery
check lamp flashes twice.
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 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, the
anti-theft alarm system will be triggered
( Y page 67).
There are several ways to turn off the alarm:
XPress the % or & button on the
SmartKey.
or
XInsert the SmartKey into the ignition lock.
or
XPress 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.
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.SmartKey73Opening and closingBA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 73Z

Problems with the SmartKeyProblemPossible causes/consequences and M SolutionsYou cannot lock/
unlock the vehicle
using the SmartKey.The SmartKey battery is discharged or nearly discharged.XPoint the tip of the SmartKey at the driver's door handle from a
distance of approximately 1.5 ft (50 cm) and try to unlock or
lock the vehicle again.
If this does not work:
XLock or unlock the vehicle using the mechanical key
( Y page 73).XCheck the key battery and replace it if necessary ( Y page 74).The SmartKey is faulty.XLock the vehicle as described in the "Locking the vehicle
(mechanical key)" section ( Y page 79) or unlock it using the
mechanical key ( Y page 73).XHave the SmartKey checked at a qualified specialist workshop.You can no longer
lock/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 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 the SmartKey checked at a qualified specialist workshop.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.You have lost a
SmartKey.XHave the SmartKey canceled at an authorized Mercedes-Benz
Center.XReport the loss immediately to the vehicle insurers.XIf necessary, have the locks changed as well.You have lost the
mechanical key.XReport the loss immediately to the vehicle insurers.XIf necessary, have the locks changed as well.76SmartKeyOpening and closing
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Rear-compartment overhead control panel
:p To switch the right-hand reading
lamp on/off
;p To switch the left-hand reading lamp
on/off
Interior lighting control
Important notes
In order to prevent the vehicle's battery from
discharging, the interior lighting functions are
automatically deactivated after some time
except for when the key is in position 2 in the
ignition lock.
Automatic interior lighting control
XTo switch on/off: press the | button.
When the automatic interior lighting
control is activated, the button is flush with
the overhead control panel.
The interior lighting automatically switches
on if you:
Runlock the vehicle
Ropen a door
Rremove the key from the ignition lock
The interior light is activated for a short while
when the key is removed from the ignition
lock. You can activate this delayed switch-off
using the on-board computer (Y page 180).
Manual interior lighting controlXTo switch the front interior lighting on/
off: press the c button.
XTo switch the rear interior lighting on/
off: press the u button.
XTo switch the reading lamps on/off:
press the p button.
Crash-responsive emergency lighting
If the interior lighting is set to automatic, the
interior lighting is activated automatically if
the vehicle is involved in an accident.
XTo switch off the crash-responsive
emergency lighting: press the hazard
warning lamp button.
or
XLock and then unlock the vehicle using the
key.
Changing bulbs
Important safety notes
Xenon bulbs
If your vehicle is equipped with Xenon bulbs,
you can recognize this by the following: the
cone of light from the Xenon bulbs moves
from the top to the bottom and back again
when you start the engine. For this to be
observed, the lights must be switched on
before starting the engine.
GWarning!
Xenon bulbs carry a high voltage. You could
get an electric shock and be seriously or even
fatally injured if you touch the electric
contacts on Xenon bulbs. Therefore, never
remove the cover from Xenon bulbs.
Do not change Xenon bulbs yourself, but have
them replaced at a qualified specialist
workshop which has the necessary specialist
knowledge and tools to carry out the work
required.
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ventilate automatically if the starter battery
is weak.XTo switch on: press the ¿ button.
The indicator lamp in the ¿ button lights
up.XTo switch off: press the ¿ button.
The indicator lamp in the ¿ button goes
out. The cooling with air dehumidification
function has a delayed switch-off feature.
Problems with the "cooling with air
dehumidification" function
If the indicator lamp in the ¿ button does
not go out when switched off, the cooling with
air dehumidification function is switched off
due to a malfunction. You can no longer
activate the cooling with air dehumidification
function.
XConsult a qualified specialist workshop.
Setting climate control to automatic
GWarning
If you switch off the cooling function, the
vehicle will not be cooled when weather
conditions are warm. The windows can fog up
more quickly. Window fogging may impair
visibility and endanger you and others.
In automatic mode, the set temperature is
maintained automatically at a constant level.
The system automatically regulates the
temperature of the dispensed air, the airflow
and the air distribution.
Automatic mode will achieve optimal
operation if cooling with air dehumidification
is also activated. If desired, cooling with air
dehumidification can be deactivated.
XTurn the SmartKey to position 2 in the
ignition lock.XSet the desired temperature.XTo activate: press the à button.
The indicator lamp in the à button lights
up. Automatic air distribution and airflow
are activated.XTo deactivate: press the _ button.
or
XPress the K or I button.
The indicator lamp in the à button goes
out. Automatic air distribution and airflow
are deactivated.
Setting the temperature
Different temperatures can be set for the
driver's and front-passenger sides.
XTurn the SmartKey to position 2 in the
ignition lock.XTo increase/reduce: turn controls : and
D clockwise or counter-clockwise
( Y page 121). Only change the temperature
setting in small increments. Start at
72 ‡ (22 †).
Setting the air distribution
Dual-zone automatic climate control: the air
distribution can be set individually for the
driver's and front-passenger sides.
¯directs the airflow through the
defroster ventsPdirects the airflow through the center
and side air ventsOdirects the airflow through the footwell
air ventsSdirects the airflow through the center
and side air vents, as well as the
footwell air vents 1515
USA only.Operating the control systems123Climate controlBA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 123Z

Display messagesPossible causes/consequences and M Solutions+
Obtain a new keyThe SmartKey needs to be replaced.XVisit a qualified specialist workshop.+
Replace Key BatteryThe batteries of the KEYLESS-GO key are discharged.XChange the batteries ( Y page 74).+
Don't Forget Your
KeyThe display message is displayed for a maximum of 60 seconds
and is just a reminder.
You have opened the driver's door with the engine switched off.
The KEYLESS-GO key is not in the ignition lock.XTake the KEYLESS-GO key with you when leaving the vehicle.+
Key Not Detected
(red display message)The KEYLESS-GO key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle
centrally or start the engine.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XLocate the KEYLESS-GO key.The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
A warning tone also sounds.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XOperate the vehicle with the KEYLESS-GO key in the ignition
lock if necessary.+
Key Not Detected
(white display
message)The KEYLESS-GO key cannot be detected at present.XChange the location of the key with the KEYLESS-GO functions
in the vehicle.
If the KEYLESS-GO key is still not detected:
XChange the location of the key with the KEYLESS-GO functions
in the vehicle.XOperate the vehicle with the KEYLESS-GO key in the ignition
lock if necessary.202Display messagesOn-board computer and displays
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