driver seat adjustment MERCEDES-BENZ C-Class SEDAN 2012 W204 Owner's Manual

XIf necessary, adjust the seat belt to the
appropriate height ( Y page 51).XIf necessary, pull upwards on the shoulder
section of the seat belt to tighten the belt
across your body.
All seat belts except the driver's seat belt are
equipped with a special seat belt retractor to
securely fasten child restraint systems in the
vehicle. For further information on special
seat belt retractors, see ( Y page 55).
For more information about releasing the seat
belt with release button ?, see "Releasing
seat belts" ( Y page 51).
Belt height adjustment
You can adjust the seat belt height on the
driver's seat and the front-passenger seat.
Adjust the height so that the upper part of the
seat belt is routed across the center of your
shoulder.
XTo raise: slide the belt sash guide upwards.
The belt sash guide engages in various
positions.XTo lower: press and hold belt sash guide
release :.XSlide the belt sash guide downwards.XRelease belt sash guide release : and
make sure that the belt sash guide has
engaged.Releasing seat beltsXPress release button ?(Y page 50) and
guide belt tongue ; back towards belt
sash guide :.
!
Make sure that the seat belt is fully rolled
up. Otherwise, the seat belt or belt tongue
will be trapped in the door or in the seat
mechanism. This could damage the door,
the door trim panel and the seat belt.
Damaged seat belts can no longer fulfill
their protective function and must be
replaced. Consult an authorized Mercedes-
Benz Center.
Belt warning for the driver and front
passenger
Regardless of whether the driver and front
passenger have fastened their seat belts
already, the 7 seat belt warning lamp
lights up for 6 seconds after every engine
start. It then goes out if the driver and the
front passenger have fastened their seat
belts.
If the driver's seat belt is not fastened after
the engine is started, an additional warning
tone will sound. The warning tone goes out
after approximately six seconds or once the
driver's seat belt is fastened.
If the driver or front passenger have not
fastened their seat belt after 6 seconds and
the doors are closed, the 7 seat belt
warning lamp lights up.
R until the driver or the front passenger have
fastened their seat belts
R if a vehicle speed of 15 mph (25 km/h) is
exceeded once, a warning tone with
increasing intensity sounds additionally for
a maximum of 60 seconds or until the driver
or front passenger have fastened their seat
belts.
If the driver or front passenger undo their seat
belts during the journey, the 7 seat belt
warning lamp lights up and the warning tone
sounds again.
Occupant safety51SafetyZ

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops ( Y page 24).
SmartKey
Important safety notes
GWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts.GWARNING
If a key ring is too heavy or too large, the
weight acting on the SmartKey could cause it
to turn in the ignition lock or catch on the
steering wheel. This could cause the engine
to be switched off suddenly. You could lose
control of the vehicle and cause an accident.
Do not attach any heavy or large key rings to
the SmartKey that is inserted in the ignition.
General notes
If you cannot lock or unlock the vehicle with
the SmartKey, either the battery in the
SmartKey is discharged, the SmartKey is
faulty or the starter battery is discharged.
XCheck the battery in the SmartKey and
replace it if necessary ( Y page 74).XUnlock the driver's door using the
mechanical key ( Y page 79).XLock the vehicle using the mechanical key
( Y page 79).XHave the starter battery and the battery
contacts checked at a qualified specialist
workshop.
If the SmartKey is faulty, contact Roadside
Assistance or a qualified specialist workshop.
SmartKey functions
General notes
i USA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful
interference, and
2. this device must accept any interference
received, including interference that may
cause undesired operation.
70SmartKeyOpening/closing

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops ( Y page 24).
Correct driver's seat position
Observe the safety guidelines on seat
adjustment ( Y page 93).
XCheck whether you have adjusted seat =
properly.
Manual and electrical seat adjustment
( Y page 94)
Electrical seat adjustment ( Y page 94)
When adjusting the seat, make sure:
R you are as far away from the driver's air
bag as possible.
R you are sitting in a normal upright
position.R you can fasten the seat belt properly.
R you have moved the backrest to an
almost vertical position.
R you have set the seat cushion angle so
that your thighs are gently supported.
R you can depress the pedals properly.XCheck whether the head restraint is
adjusted properly ( Y page 95).
When doing so, make sure that you have
adjusted the head restraint so that the back
of your head is supported at eye level by
the center of the head restraint.
Observe the safety guidelines on steering
wheel adjustment ( Y page 99).
XCheck whether steering wheel : is
adjusted properly.
Adjusting the steering wheel
manually( Y page 99)
Adjusting the steering wheel electrically
( Y page 100)
When adjusting the steering wheel, make
sure:
R you can hold the steering wheel with your
arms slightly bent.
R you can move your legs freely.
R you can see all the displays in the
instrument cluster clearly.
Observe the safety guidelines for seat belts
( Y page 48).
XCheck whether you have fastened seat
belt ; properly ( Y page 50).
The seat belt should:
R fit snugly across your body
R be routed across the middle of your
shoulder
R be routed in your pelvic area across the
hip jointsXBefore starting off, adjust the rear-view
mirror and the exterior mirrors92Correct driver's seat positionSeats, steering wheel and mirrors

(Y page 101) in such a way that you have
a good view of road and traffic conditions.XVehicles with a memory function: save
the seat, steering wheel and exterior mirror
settings ( Y page 103).
Seats
Important safety notes
GWARNING
In order to avoid possible loss of vehicle
control, all seat, head restraint, steering
wheel and rear view mirror adjustments, as
well as fastening of seat belts, must be done
before setting the vehicle in motion.
GWARNING
Do not adjust the driver's seat while driving.
Adjusting the seat while driving could cause
the driver to lose control of the vehicle.
Never travel in a moving vehicle with the seat
backrest in an excessively reclined position as
this can be dangerous. You could slide under
the seat belt in a collision. If you slide under
it, the seat belt would apply force at the
abdomen or neck. This could cause serious or
fatal injuries. The seat backrest and seat belts
provide the best restraint when the wearer is
in a position that is as upright as possible and
seat belts are properly positioned on the
body.
GWARNING
Your seat belt must be adjusted so that you
can correctly fasten your seat belt.
Observe the following points:
R adjust the seat backrest until your arms are
slightly angled when holding the steering
wheel.
R adjust the seat to a comfortable seating
position that still allows you to reach the
accelerator/brake pedal safely. The
position should be as far back as possible
with the driver still able to operate the
controls properly.
R adjust the head restraint so that it is as
close to the head as possible and the center
of the head restraint supports the back of
the head at eye level.
R never place hands under the seat or near
any moving parts while a seat is being
adjusted.
Failure to do so could result in an accident
and/or serious personal injury.GWARNING
The electrically adjustable seats 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.
GWARNING
According to accident statistics, children are
safer when properly restrained in the rear
seating positions than in the front seating
position. Thus, we strongly recommend that
children be placed in the rear seats whenever
possible. Regardless of seating position,
children 12 years old and under must be
seated and properly secured in an
appropriately sized infant restraint, toddler
restraint, or booster seat recommended for
the size and weight of the child. For additional
information, see "Children in the vehicle".
A child's risk of serious or fatal injuries is
significantly increased if the child restraints
are not properly secured in the vehicle and/
or the child is not properly secured in the child
restraint.
GWARNING
For your protection, drive only with properly
positioned head restraints.
Adjust the head restraint so that it is as close
to the head as possible and the center of the
head restraint supports the back of the head
at eye level. This will reduce the potential for
Seats93Seats, steering wheel and mirrorsZ

:To adjust the upper back support;To adjust the contour of the backrest in
the lumbar region=To adjust the lateral structure and support
of the seatXMake sure that the SmartKey is in position
2 in the ignition lock.
i
If, after a certain amount of time, the seat
no longer has the desired contour, repeat
the adjustment.
Switching the seat heating on/off
Switching on/off
GWARNING
Repeatedly setting the seat heating to level
3 may result in excessive seat temperatures.
The health of passengers that have limited
temperature sensitivity or a limited ability to
react to excessively high temperatures may
be affected or they may even suffer burn-like
injuries. Therefore, do not use seat heating
level 3 repeatedly.
The three red indicator lamps in the button
indicate the heating level you have selected.
i If the battery voltage is too low, the seat
heating may switch off.
Driver's and front-passenger seat
The system automatically switches down
from level 3 to level 2 after approximately
eight minutes.
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
1 or 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.
98SeatsSeats, steering wheel and mirrors

iIf 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 84). 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.
Steering wheel
Important safety notes
GWARNING
Do not adjust the steering wheel while driving.
Adjusting the steering wheel while driving, or
driving without the steering wheel adjustment
feature locked 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
manually
:Release lever;To adjust the steering wheel height=To adjust the steering wheel position
(fore-and-aft adjustment)XPush release lever : down completely.
The steering column is unlocked.XAdjust the steering wheel to the desired
position.XPush release lever : up completely.
The steering column is locked.XCheck if the steering column is locked.
When doing so, try to push the steering
wheel up or down or try to move it in the
fore-and-aft direction.Steering wheel99Seats, steering wheel and mirrorsZ

Adjusting the steering wheel
electrically: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 100)
R storing settings ( Y page 103)
EASY-ENTRY/EXIT system
Important safety notes
The EASY-ENTRY/EXIT feature makes getting
in and out of your vehicle easier.
You can activate and deactivate the EASY-
ENTRY/EXIT feature in the on-board
computer ( Y page 209).
GWARNING
You must make sure no one can become
trapped or injured by the moving steering
wheel when the easy-entry/exit feature is
activated.
To stop steering wheel movement, move
steering wheel adjustment stalk or press the
memory position switch.
Do not leave children unattended in the
vehicle, or with access to an unlocked vehicle.
Children could open the driver's door and
unintentionally activate the easy-entry/exit
feature, which could result in an accident
and/or serious personal injury.
GWARNING
Let the system complete the adjustment
procedure before setting the vehicle in
motion. All steering wheel adjustment must
be completed before setting the vehicle in
motion. Driving off with the steering wheel
still adjusting could cause the driver to lose
control of the vehicle.
Position of the steering wheel when the
EASY-ENTRY/EXIT feature is active
The steering wheel swings upwards when
you:
R remove the SmartKey from the ignition lock
R open the driver's door and KEYLESS-GO is
in position 1
R open the driver's door and the SmartKey is
in position 0 or 1 in the ignition lock
i The steering wheel only moves upwards if
it has not already reached the upper end
stop.
Position of the steering wheel for
driving
The steering wheel is moved to the last
selected position when:
R the driver's door is closed.
R you insert the SmartKey into the ignition
lock.
or
R you press the Start/Stop button once on
vehicles with KEYLESS-GO.
When you close the driver's door with the
ignition switched on, the steering wheel is
also automatically moved to the previously
set position.
The last position of the steering wheel is
stored after each manual setting or when you
store the setting with the memory function
( Y page 103).
100Steering wheelSeats, steering wheel and mirrors

Crash-responsive EASY-EXIT feature
If the crash-responsive EASY-EXIT feature is
triggered in an accident, the steering column
will move upwards when the driver's door is
opened. This occurs irrespective of the
position of the SmartKey in the ignition lock.
This makes it easier to exit the vehicle and
rescue the occupants.
The crash-responsive EASY-EXIT feature is
only operational if the EASY-EXIT/ENTRY
feature is activated in the on-board computer.
Mirrors
Rear-view mirror
Rear-view mirror (manual anti-glare)
Xanti-glare mode: flick anti-glare
switch : forwards or back.
Exterior mirrors
Adjusting the exterior mirrors
GWARNING
Exercise care when using the passenger-side
exterior rear view mirror. The mirror surface
is convex (outwardly curved surface for a
wider field of view). Objects in mirror are
closer than they appear. Check your interior
rear view mirror and glance over your
shoulder before changing lanes.
The exterior mirrors are automatically heated
if the rear window defroster is switched on
and the outside temperature is low.XMake sure that the SmartKey is in position
1 or 2 in the ignition lock.XPress button : for the left-hand exterior
mirror or button ; for the right-hand
exterior mirror.
The indicator lamp in the corresponding
button lights up in red.
The indicator lamp goes out again after
some time. You can adjust the selected
mirror using adjustment button = as long
as the indicator lamp is lit.XPress adjustment button = up, down, to
the right or to the left until the exterior
mirror is set to a position that provides you
with a good overview of traffic conditions.
Folding the exterior mirrors in or out
electrically
This function is only available in vehicles for
Canada.
Mirrors101Seats, steering wheel and mirrorsZ

engage reverse gear. You can store this
position.XMake sure that the vehicle is stationary and
that the SmartKey is in position 2 in the
ignition lock.XPress button ; for the exterior mirror on
the front-passenger side.XEngage reverse gear.
The exterior mirror on the front-passenger
side moves to the preset parking position.XUse adjustment button = to adjust the
exterior mirror to a position that allows you
to see the rear wheel and the curb.
The parking position is stored.
i If you shift the transmission to another
position, the exterior mirror on the front-
passenger side returns to the driving
position.
i You can also store the parking position
using memory button M ? .
XMake sure that the SmartKey is in
position 2 in the ignition lock.XWith the exterior mirror on the front-
passenger side activated, use
adjustment button = to adjust the
exterior mirror to a position which
allows you to see the rear wheel and
the curb.XPress memory button M ? and one of
the arrows on adjustment button =
within three seconds.
The parking position is stored if the
exterior mirror does not move.If the mirror moves out of position, repeat
the steps.
Calling up a stored parking position
settingXTurn the SmartKey to position 2 in the
ignition lock.XAdjust the exterior mirror on the front-
passenger side with the corresponding
button ( Y page 101).XEngage reverse gear.
The exterior mirror on the front-passenger
side moves to the stored parking position.
The exterior mirror on the front-passenger
side moves back to its original position:
R as soon as you exceed a speed of 6 mph
(10 km/h)
R about ten seconds after you have
disengaged reverse gear
R if you press button : for the exterior
mirror on the driver's side
Memory function
Storing settings
With the memory function, you can store up
to three different settings, e.g. for three
different people.
The following settings are stored as a single
memory preset:
R position of the seat, backrest and head
restraint
R driver's side: steering wheel position
R driver's side: position of the exterior
mirrors on the driver's and front-passenger
sides
GWARNING
Do not activate the memory function while
driving. Activating the memory function while
driving could cause the driver to lose control
of the vehicle.
Memory function103Seats, steering wheel and mirrorsZ

XMove the selector lever to P to prevent the
vehicle from rolling away.
DISTRONIC PLUS is deactivated. The
warning message in the multifunction
display disappears.
The horn will also sound at regular intervals if
DISTRONIC PLUS is activated and you:
R switch the engine off, open the driver's
door and take off your seat belt
R open the hood
The sounding of the horn alerts you to the fact
that the vehicle has been parked while
DISTRONIC PLUS is still activated. The sound
becomes louder if you attempt to lock the
vehicle. The vehicle is not locked until
DISTRONIC PLUS is deactivated.
i If the engine has been switched off, it
cannot be started again until DISTRONIC
PLUS has been deactivated.
If DISTRONIC PLUS is activated and a
malfunction occurs in the system or if there
is a disruption in the power supply, the
Brake Immediately message is shown in
the multifunction display. Immediately
depress the brake firmly until the warning
message in the multifunction display goes out
or shift the transmission to position P.
DISTRONIC PLUS is then deactivated.
Setting a speed
GWARNING
Keep in mind that it may take a brief moment
until the vehicle has made the necessary
adjustments.
Increase or decrease the set vehicle speed to
a value that the prevailing road conditions and
legal speed limits permit. Otherwise, sudden
and unexpected acceleration or deceleration
of the vehicle could cause an accident and/
or serious injury to you and others.
XPress the cruise control lever up : for a
higher speed or down ; for a lower speed.XKeep the cruise control lever pressed until
the desired speed is reached.XRelease the cruise control lever.
The new speed is stored. DISTRONIC PLUS
is activated and adjusts the vehicle's speed
to the new speed stored.
Making adjustments in 1 mph (Canada:
1 km/h) increments
XBriefly press the cruise control lever to the
pressure point, up : for a higher speed or
down ; for a lower speed.
The last speed stored is increased or
reduced.
Making adjustments in 5 mph (Canada:
10 km/h) increments
XBriefly press the cruise control lever
beyond the pressure point, up : for a
higher speed or down ; for a lower speed.
The last speed stored is increased or
reduced.
Storing the current speed or calling up
a stored speed
GWARNING
The set speed stored in memory should only
be set again if prevailing road conditions and
legal speed limits permit. Possible
acceleration or deceleration differences
arising from returning to the preset speed
could cause an accident and/or serious injury
to you and others.
XBriefly pull the cruise control lever towards
you ?.XRemove your foot from the accelerator
pedal.
DISTRONIC PLUS is activated. The first
time it is activated, the current speed is
stored. Otherwise, it sets the vehicle cruise
speed to the previously stored value.Driving systems167Driving and parkingZ