child lock MERCEDES-BENZ C-Class SEDAN 2012 W204 Owner's Manual

CareCarpets .......................................... 289
Car wash ........................................ 284
Display ........................................... 288
Exterior lights ................................ 287
Gear or selector lever ....................288
Matte finish ................................... 285
Notes ............................................. 283
Paint .............................................. 285
Plastic trim .................................... 288
Power washer ................................ 284
Rear view camera .......................... 287
Roof lining ...................................... 289
Seat belt ........................................ 289
Seat cover ..................................... 288
Sensors ......................................... 287
Steering wheel ............................... 288
Tail pipes ....................................... 287
Trim pieces .................................... 288
Washing by hand ........................... 284
Wheels ........................................... 285
Windows ........................................ 286
Wiper blades .................................. 286
Wooden trim .................................. 288
Cargo tie down rings ......................... 258
Car wash (care) ................................. 284
CD player/CD changer (on-board
computer) .......................................... 202
Cell phone see Mobile phone
Center console ..................................... 32
Central locking Automatic locking (on-board
computer) ...................................... 208
Locking/unlocking (SmartKey) ........70
Changing bulbs
Brake lamps ................................... 116
Cornering light function .................115
High-beam headlamps ...................115
Important safety notes ..................113
Low-beam headlamps ....................114
Overview of bulb types ..................114
Parking lamps ................................ 115
Reversing lamps ............................ 116
Standing lamps (front) ...................115
Child-proof locks
Important safety notes ....................57
Rear doors ....................................... 57Children
In the vehicle ................................... 53
Restraint systems ............................ 53
Child seat
LATCH-type (ISOFIX) child seat
anchors ............................................ 55
Special seat belt retractor ...............55
Top Tether ....................................... 56
Cigarette lighter ................................ 262
Climate control Automatic climate control (3-
zone) .............................................. 125
Controlling automatically ...............127
Cooling with air dehumidification ..126
Defrosting the windows .................130
Defrosting the windshield ..............129
Dual-zone automatic climate
control ........................................... 123
Important safety notes ..................122
Indicator lamp ................................ 127
Maximum cooling .......................... 130
Notes on using automatic climate
control ................................... 124, 126
Overview of systems ......................122
Problems with cooling with air
dehumidification ............................ 127
Problem with the rear window
defroster ........................................ 130
Rear control panel .........................125
Refrigerant ..................................... 350
Setting the air distribution .............128
Setting the airflow .........................129
Setting the air vents ......................131
Setting the climate mode (AIR
FLOW) ............................................ 127
Setting the temperature ................128
Switching air-recirculation mode
on/off ............................................ 130
Switching on/off ........................... 126
Switching residual heat on/off ......131
Switching the rear window
heating on/off ............................... 130
Switching the ZONE function on/
off .................................................. 129
Cockpit
Overview .......................................... 28
see Instrument cluster 6Index

High-beam headlampsChanging bulbs .............................. 115
Display message ............................ 223
Switching Adaptive Highbeam
Assist on/off ................................. 110
Switching on/off ........................... 109
Hill start assist .................................. 140
HOLD function Display message ............................ 228
Function/notes ............................. 172
Hood
Closing ........................................... 279
Display message ............................ 237
Opening ......................................... 278
Hydroplaning ..................................... 158
I
Ignition lock see Key positions
Immobilizer .......................................... 66
Indicator lamps see Warning and indicator lamps
Indicators
see Turn signals
Instrument cluster
Overview .......................................... 29
Settings ......................................... 206
Warning and indicator lamps ...........30
Instrument cluster lighting ................ 29
Instrument lighting see Instrument cluster lighting
Interior lighting ................................. 112
Automatic control ..........................112
Delayed switch-off (on-board
computer) ...................................... 208
Emergency lighting ........................113
Manual control ............................... 113
Overview ........................................ 112
Reading lamp ................................. 112
J
Jack Storage location ............................ 292
Using ............................................. 295
Jump starting (engine) ...................... 301
K
Key see SmartKey
KEYLESS-GO
Convenience closing feature ............85
Display message ............................ 238
Locking ............................................ 71
Start/Stop button .......................... 137
Starting the engine ........................139
Unlocking ......................................... 71
Key positions
KEYLESS-GO .................................. 137
SmartKey ....................................... 137
Kickdown
Driving tips .................................... 144
Manual drive program ....................148
Knee bag .............................................. 40
L
Lamps see Warning and indicator lamps
Lane-change assistant
see Blind Spot Assist
Lane detection (automatic)
see Lane Keeping Assist
Lane Keeping Assist
Activating/deactivating .................205
Display message ............................ 229
Function/information ....................185
Lane Tracking package ..................... 183
Lap time (RACETIMER) ...................... 211
LATCH-type (ISOFIX) child seat
anchors ................................................ 55
Lighting see Lights
Lights
Activating/deactivating the
interior lighting delayed switch-off . 208
Active light function .......................110
Automatic headlamp mode ............108
Cornering light function .................110
Display message ............................ 222
Driving abroad ............................... 106
Fog lamps ...................................... 108
Hazard warning lamps ...................109
High beam flasher .......................... 109
Index11

Useful information ..............................36
Occupant safety .................................. 36
Children in the vehicle ........................53
Panic alarm .......................................... 58
Driving safety systems .......................58
Theft deterrent locking systems .......6635Safety

If the SmartKey has been removed from the
ignition lock or is in position 0, indicator lamp
45 : does not light up.
GWARNING
If the red 6 SRS warning lamp in the
instrument cluster and the 45
indicator lamp light up simultaneously, the
OCS is malfunctioning. The front passenger
front air bag will be deactivated in this case.
Have the system checked by qualified
technicians as soon as possible. Contact an
authorized Mercedes-Benz Center.
Only have the seat repaired or replaced at an
authorized Mercedes-Benz Center.
In order to ensure proper operation of the air
bag system and OCS:
R Sit with the seat belt properly fastened in a
position that is as upright as possible with
your back against the seat backrest.
R When seated, a passenger should not
position him/herself in such a way as to
cause the passenger's weight to be lifted
from the seat cushion as this may result in
the OCS being unable to correctly
approximate the passenger's weight
category.
R Read and observe all warnings in this
chapter.
System self-test
The 45 indicator lamp illuminates
when you:
R turn the SmartKey to position 1 or 2 in the
ignition lock
R on vehicles with KEYLESS-GO, press the
Start/Stop button once or twice
If an adult occupant is properly sitting on the
passenger seat and the OCS classifies the
occupant as an adult, the 45 indicator
lamp illuminates and goes out again after
approximately 6 seconds.
If the seat is not occupied and the OCS
classifies the front passenger seat as being
unoccupied, the 45 indicator lamp
will illuminate and not go out.
GWARNING
If the 4 5 indicator lamp does not
illuminate, the system is not functioning. You
must contact an authorized Mercedes-Benz
Center before seating any child on the front
passenger seat.
For more information, see "Problems with the
Occupant Classification System"
( Y page 46).
GWARNING
Never place anything between seat cushion
and child seat (e.g. a pillow), since it reduces
the effectiveness of the OCS. The underside
and rear side child restraint system must be
placed entirely on the seat cushion and the
backrest of the front-passenger seat
backrest.
If necessary, adjust the tilt of the passenger
seat backrest.
An incorrectly mounted child seat could cause
injuries to the child in case of an accident,
instead of increasing protection for the child.
Follow the manufacturer's instructions for
installation of child restraint systems.
Occupant safety45SafetyZ

passenger front air bag is deactivated.
Should the 4 5 indicator lamp not
illuminate or go out while the restraint is
installed, please check installation.
Periodically check the 4 5 indicator
lamp while driving to make sure the 4
5 indicator lamp is illuminated. If the
4 5 indicator lamp goes out or
remains out, do not transport a child on the
front passenger seat until the system has
been repaired.
A child in a rear-facing child restraint on the
front passenger seat will be seriously
injured or even killed if the front passenger
front air bag inflates.
R If you have to place a child in a forward-
facing child restraint on the front passenger
seat, move the seat as far back as possible,
use the proper child restraint
recommended for the age, size and weight
of the child, and secure child restraint with
the vehicle's seat belt according to the
child seat manufacturer's instructions.GWARNING
Infants and small children should never share
a seat belt with another occupant. During an
accident, they could be crushed between the
occupant and seat belt.
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.
Children too big for a toddler restraint must
ride in seats using regular seat belts. Position
the shoulder belt across the chest and
shoulder, not face or neck. A booster seat
may be necessary to achieve proper seat belt
positioning for children over 41 lb (18 kg) until
they reach a height where a lap/shoulder belt
fits properly without a booster.
When the child restraint is not in use, remove
it from the vehicle or secure it with the seat
belt to prevent the child restraint from
becoming a projectile in the event of an
accident.
If an infant or child is traveling in the vehicle:XSecure the infant or child with an
appropriate infant or child restraint
recommended for the child's age and
weight.XMake sure that the infant or child is
properly secured at all times while the
vehicle is in motion.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 unattended in the
vehicle, even if they are secured in a child
restraint system, 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. The children
could:
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
ignition lock or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following 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 the child could be burned on these
parts.
GWARNING
Do not carry heavy or hard objects in the
passenger compartment or trunk unless they
are firmly secured in place.
54Children in the vehicleSafety

Vehicles without rear-seat through-loading facility
Installation instructions : indicate the
installation location of securing rings =.
XRemove covers ; from securing rings =
by pulling in the direction of the arrow.
Vehicles with rear-seat through-loading facility
XInstall the LATCH-type (ISOFIX) child
restraint system. Comply with the
manufacturer's instructions when
installing the LATCH-type (ISOFIX) child
restraint system.
Top Tether
GWARNING
Always lock the rear seat backrests in their
upright position when the rear seats are
occupied by passengers. Lock the rear seat
backrests in their upright position before
installing the Top Tether straps or when the
cargo compartment is not in use. Make sure
that rear seat backrests are secured properly
by pushing and pulling on the seat backrests.
If the seat backrest is not locked properly, the
seat backrest could fold forward. The child
restraint system is no longer supported
properly or held in position and can no longer
fulfill its function. This could cause serious or
even fatal injuries.
Top Tether provides an additional connection
between the child restraint system secured
with ISOFIX and the rear seat. It helps reduce
the risk of injury even further.
The Top Tether anchorage points are located
in the rear compartment behind the head
restraints.XMove head restraint : upwards.XFold up cover ; of Top Tether anchorage
= .XRoute Top Tether belt A under head
restraint : between the two head restraint
bars.XHook Top Tether hook ? into Top Tether
anchorage =.XMake sure that Top Tether belt A is not
twisted.56Children in the vehicleSafety

XFold down cover ; of Top Tether
anchorage =.XMove head restraint : back down again
slightly if necessary ( Y page 96). Make
sure that you do not interfere with the
correct routing of Top Tether belt A.XInstall the LATCH-type (ISOFIX) child
restraint system with Top Tether. Comply
with the manufacturer's installation
instructions when doing so. Make sure that
Top Tether belt A is tight.
Child-proof locks
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 unattended in the
vehicle, even if they are secured in a child
restraint system, 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. The children
could:
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
ignition lock or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following 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 the child could be burned on these
parts.
Child-proof locks for the rear doorsGWARNING
Children could open a rear door from inside
the vehicle. This could result in serious
injuries or an accident. Therefore, when
children ride in the rear always secure the rear
doors with the child-proof locks.
You secure each door individually with the
child-proof locks on the rear doors. A door
secured with a child-proof lock cannot be
opened from inside the vehicle. When the
vehicle is unlocked, the door can be opened
from the outside.
XTo activate: press the child-proof lock
lever up in the direction of arrow :.XMake sure that the child-proof locks are
working properly.XTo deactivate: press the child-proof lock
lever down in the direction of arrow ;.
Override feature for the rear side
windows
GWARNING
When children ride on the vehicle's rear seats,
activate the override switch. Otherwise, the
children could be injured, e.g. by trapping
themselves in the rear side window.
Children in the vehicle57SafetyZ

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

Removing the mechanical keyXPush 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 74)
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 73).XPress mechanical key ; into the opening
in the SmartKey in the direction of the74SmartKeyOpening/closing

ProblemPossible causes/consequences and M SolutionsThe 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 298).
or
XJump-start the vehicle ( Y page 301).
or
XConsult a qualified specialist workshop.The engine cannot be
started using the
SmartKey.The steering lock is mechanically blocked.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.Doors
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
Do not carry heavy or hard objects in the
passenger compartment or trunk unless they
are firmly secured in place.
Doors77Opening/closingZ