2011 MERCEDES-BENZ M-Class child lock

ISOFIX is a standardized securing system for
specially-designed child restraint systems on
the rear seats. Securing rings for two ISOFIX
child restraint systems are installed on the
left and right of the rear seats.
Install child restraint systems without the
ISOFIX securing system using the vehicle's
seat belts. Follow the manufacturer's
instructions for installation of child restraint
systems.
! When installing the child restraint system,
make sure that the seat belt for the center
seat does not get trapped. Otherwise, the
seat belt could be damaged.XRemove covers :.;Securing ringsXInstall the ISOFIX child restraint system.
Comply with the manufacturer's
instructions when installing the ISOFIX
child restraint system.Top TetherGWarning
Observe "Important safety instructions"
( Y page 58).
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. That 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 anchorages are located on the
rear of the rear seat backrests.
XRemove respective covering cap : of the
Top Tether anchorage.62Children in the vehicleSafety
BA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 62

XMove the head restraint upwards.XInstall the ISOFIX child restraint system
with Top Tether. Comply with the
manufacturer's installation instructions
when doing so.XRoute Top Tether belt ? under the head
restraint between the two head restraint
bars.XRoute Top Tether belt ? downwards
between the cargo compartment cover and
rear seat backrest.XHook Top Tether hook = of Top Tether
belt ? into Top Tether anchorage ;.
Ensure that:
R Top Tether hook = is hooked into Top
Tether anchorage ; as shown
R Top Tether belt ? is not twisted
R Top Tether belt ? is routed between the
rear seat backrest and the cargocompartment cover if the cargo
compartment cover is installed
R Top Tether belt ? is routed between the
rear seat backrest and the cargo net if
the cargo net is installed.XTension Top Tether belt ?. Comply with
the manufacturer's installation
instructions when doing so.XMove the 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 ?.
Child-proof locks
Child-proof locks for the rear doors
GWarning
Observe "Important safety instructions"
( Y page 58).
GWarning
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.
Children in the vehicle63SafetyBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 63Z

XTo activate: press the child-proof lock
lever down in the direction of arrow ;.XMake sure that the child-proof locks are
working properly.XTo deactivate: press the child-proof lock
lever up in the direction of arrow :.
Override feature for the rear side
windows
GWarning
Observe "Important safety instructions"
( Y page 58).
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.
XTo activate/deactivate: press switch :.
Switch : engages or extends. If the switch
is pushed in, it is only possible to operate
the side windows in the rear using the
switches on the driver's door.Panic alarmX To activate: press and hold !
button : for about one second.
An alarm sounds and the exterior lighting
flashes.XTo deactivate: press ! button :
again.
or
XInsert the SmartKey into the ignition lock.
or
XPress the KEYLESS-GO Start-Stop button.
The KEYLESS-GO key must be in the
vehicle.
i USA only:
This device complies with the part 15 of the
FCC regulations. Operation is subject to
the following two conditions:
1. This device may not cause interference,
and
2. This device must withstand any
interference received, including
interference that may cause undesired
operation.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
i Canada only:
This device complies with the RSS-210
regulations of Industry Canada. Operation
is subject to the following two conditions:
1. This device may not cause interference,
and
64Panic alarmSafety
BA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 64

Vehicle equipment
i This manual describes all the standard
and optional equipment of your vehicle
which was available at the time of
purchase. Country-specific differences are
possible. Bear in mind that your vehicle
may not feature all functions described
here. This also refers to safety-related
systems and functions.
SmartKey
Important safety guidelines
GWarning!
When leaving the vehicle, always remove the
SmartKey from the starter switch. 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
starter switch 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 by these
parts.
GWarning!
Do not carry heavy or hard objects in the
passenger compartment or cargo
compartment unless they are firmly secured
in place.
Unsecured or improperly positioned cargo
increases a child’s risk of injury in the event
of
R strong braking maneuvers
R sudden changes of direction
R an accident
General information
If you cannot open or lock the vehicle with the
SmartKey, either the battery in the SmartKey
is empty, the SmartKey is faulty, or the vehicle
battery is discharged.
XCheck the battery in the SmartKey and
replace it if necessary ( Y page 76).XUnlock the driver's door using the
mechanical key ( Y page 75).XLock the vehicle using the mechanical key
( Y page 75).XHave the vehicle battery and battery
contacts checked by an authorized
Mercedes-Benz Center.
If the SmartKey is faulty, contact Roadside
Assistance or an authorized Mercedes-Benz
Center.
SmartKey functions
General notes
i USA only:
This device complies with Part 15 of the
FCC regulations. Operation is subject to
the following conditions:
1. This device must not cause any harmful
interference, and
2. This device must be able to
accommodate interference that is
72SmartKeyOpening and closing
BA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 72

GWarning
Batteries contain toxic and caustic
substances. For this reason, keep batteries
out of the reach of children.
If a battery has been swallowed, seek medical
help immediately.
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 battery
XPress the & or % button.
The SmartKey battery is working properly if
battery charge indicator lamp : lights up
briefly.
If battery charge indicator lamp : does not
light up briefly during the test, the SmartKey
battery is discharged.
XReplace the SmartKey battery
( Y page 76).
i
You can obtain a SmartKey battery at any
authorized Mercedes-Benz Center.
i If the SmartKey battery is checked within
signal range of the vehicle, pressing the
& or % button results in the vehicle
being locked or unlocked respectively.
Changing the battery
You require a CR 2025 3 V cell battery.
XTake the mechanical key out of the
SmartKey ( Y page 75).XPress mechanical key ; into the opening
in the SmartKey in the direction of the
arrow until battery tray cover : opens. Do
not hold the cover closed while doing so.XRemove the cover of the battery tray.XRepeatedly tap the SmartKey against your
palm until battery = falls out.XInsert the new battery with the positive
pole facing upwards. Use a lint-free cloth to
do so.XInsert the front tabs of the battery tray's
cover first and then press to close it.XCheck the function of all SmartKey buttons
on the vehicle.76SmartKeyOpening and closing
BA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 76

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 312).
or
XJump-start the vehicle ( Y page 315).
or
XConsult a qualified specialist workshop.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 guidelines
GWarning!
When leaving the vehicle, always remove the
SmartKey from the starter switch. 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
starter switch 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 by these
parts.GWarning!
Do not carry heavy or hard objects in the
passenger compartment or cargo
compartment unless they are firmly secured
in place.
Unsecured or improperly positioned cargo
increases a child’s risk of injury in the event
of
R strong braking maneuvers
R sudden changes of direction
R an accident
78DoorsOpening and closing
BA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 78

Unlocking and opening doors from
the inside
You can open a door from inside the vehicle
even if it has been locked, unless the child-
proof locks have been activated (Y page 63).
Open the door only when the traffic
conditions permit.
If the vehicle has been opened with the
SmartKey or KEYLESS-GO key, opening from
inside triggers the anti-theft alarm system.
Switch off the alarm ( Y page 69).XPull door handle ;.
If the door is locked, locking knob : pops
up. The door is unlocked and can be
opened.
Centrally locking and unlocking the
vehicle from the inside
You can centrally lock or unlock the vehicle
from the inside. This feature may be useful if,
for example, you wish to unlock the front-
passenger door from the inside or lock the
vehicle before you pull away.
The central locking/unlocking button does
not lock or unlock the fuel filler flap.
The buttons are located on both front doors.
i You cannot unlock the vehicle centrally
from the inside if the vehicle has been
locked with the SmartKey or KEYLESS-GO.
i It is only possible to lock the vehicle
centrally if the front-passenger door is
closed.
XTo lock: press button ;.
The vehicle locks itself when all doors and
the tailgate are closed.XTo unlock: press button :.
You can open a front door from inside the
vehicle even if it has been locked. Open the
door only when the traffic conditions permit.
If the vehicle has been locked with the locking
button for the central locking function:
R and the SmartKey has been reset to the
factory settings, the complete vehicle is
unlocked when a front door is opened from
the inside
R and the SmartKey has been set to an
individual setting, only the front door that
is opened from the inside is unlocked
If the vehicle has been locked centrally with
the SmartKey or with KEYLESS-GO, it is not
unlocked if you use the unlocking button for
the central locking system.
Automatic locking
The vehicle locks automatically when the
ignition is switched on and the wheels of the
vehicle are moving at a speed above 9 mph
(15 km/h) . Therefore, there is a risk of being
locked out when the vehicle is being pushed,
towed or tested on a dynamometer.
You can switch the automatic locking
function on and off using the on-board
computer ( Y page 217).
Doors79Opening and closingBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 79Z

Unlocking the driver's door
(mechanical key)
If the vehicle can no longer be unlocked
centrally with the SmartKey or KEYLESS-GO:XTake the mechanical key out of the
SmartKey ( Y page 75).XInsert the mechanical key into the lock of
the driver's door as far as it will go.XFirmly turn the mechanical key counter-
clockwise as far as it will go to position
1 and hold it in this position.XPull the door handle quickly.
The locking knob pops up.
The door is unlocked.XTurn the mechanical key back and remove
it.XPull the door handle again.
Locking the vehicle
If the vehicle can no longer be locked
centrally with the SmartKey or KEYLESS-GO:
XClose the front-passenger door, the rear
door on the front-passenger side and the
tailgate.XOpen the driver’s door and the rear door on
the driver’s side.XPress the locking button on the driver’s
door ( Y page 79).
The locking knobs in the front-passenger
door and in the rear doors drop down.XPress down the locking knobs in the front-
passenger and rear doors manually, if
necessary.XClose the driver's door from the outside.XPress down the locking knob of the driver's
door by reaching in through the open rear
door.
i Make sure that you have the SmartKey on
your person and that it has not been left in
the vehicle.
XClose the rear door on the driver’s side.XMake sure that the doors and the tailgate
are locked.
i If you lock the vehicle as described above,
the fuel filler flap is not locked. The anti-
theft alarm system is not primed.
Cargo compartment
Important safety guidelines
Do not leave the SmartKey in the cargo
compartment. You could otherwise lock
yourself out.
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.
80Cargo compartmentOpening and closing
BA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 80