2014 MERCEDES-BENZ M-Class change key battery

seconds until the battery check lamp
flashes twice (Y
page 83).
i If the setting of the locking system is
changed within the signal range of the
vehicle, pressing the 000Bor000C button:
R locks or
R unlocks the vehicle
The SmartKey now functions as follows:
X To unlock the driver's door: press the
000C button once.
X To unlock centrally: press the000C
button twice.
X To lock centrally: press the000Bbutton.
The KEYLESS-GO function is changed as
follows:
X To unlock the driver's door: touch the
inner surface of the door handle on the
driver's door.
X To unlock centrally: touch the inner
surface of the door handle on the front-
passenger door or the rear door.
X To lock centrally: touch the outer sensor
surface on one of the door handles
(Y page 81).
X To restore the factory settings: press
and hold down the 000Cand000B buttons
simultaneously for approximately six
seconds until the battery check lamp
flashes twice (Y page 83). 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, the anti-theft alarm
system will be triggered (Y
page 76).There are several ways to turn off the alarm:
X
To turn the alarm off with the
SmartKey: press the000Cor000B button
on the SmartKey.
or
X Insert the SmartKey into the ignition lock.
or
X To deactivate the alarm with KEYLESS-
GO: press the Start/Stop button in the
ignition lock. The SmartKey must be in the
vehicle.
or
X Lock 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.
X To unlock the fuel filler flap: insert the
SmartKey into the ignition lock.
Removing the mechanical key 0002
Release catch
0003 Mechanical key
X Push release catch 0002in the direction of
the arrow and at the same time remove
mechanical key 0003from the SmartKey.
For further information about:
R unlocking the driver's door (Y page 88)
R unlocking the cargo compartment
(Y page 93)
R locking the vehicle (Y page 88)82
SmartKeyOpening and closing

SmartKey battery
Important safety notes G
WARNING
Batteries contain toxic and corrosive
substances. If batteries are swallowed, it can
result in severe health problems. There is a
risk of fatal injury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
Mercedes-Benz recommends that you have
the batteries replaced at a qualified specialist
workshop.
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. National
guidelines must be observed during disposal.
In California, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/index.cfm.
Checking the battery X
Press the 000Bor000C button.
The battery is working properly if battery
check lamp 0002lights up briefly.
The battery is discharged if battery check
lamp 0002does not light up briefly.
X Change the battery (Y page 83).
i If the SmartKey battery is checked within
the signal reception range of the vehicle,
pressing the 000Bor000C button:
R locks or
R unlocks the vehicle i
You can get a battery at any qualified
specialist workshop.
Replacing the battery You require a CR 2025 3 V cell battery.
X
Take the mechanical key out of the
SmartKey (Y page 82). 0002
Battery compartment cover
0003 Mechanical key
X Press mechanical key 0003into the opening
in the SmartKey in the direction of the
arrow until battery compartment cover 0002
opens. Do not hold battery compartment
cover 0002closed while doing so.
X Remove battery compartment cover 0002. 0023
Battery SmartKey
83Opening and closing Z

Problems with the SmartKey
Problem Possible causes/consequences and
0001 Solutions
You cannot lock or
unlock the vehicle
using the SmartKey. The SmartKey battery is discharged or nearly discharged.
X
Try 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 000Cor
000B button.
If this does not work:
X Check the SmartKey battery (Y page 83) and replace it if
necessary (Y page 83).
X Lock (Y page 88) or unlock (Y page 88) the vehicle using
the mechanical key. The SmartKey is faulty.
X
Lock (Y page 88) or unlock (Y page 88) the vehicle using
the mechanical key.
X Have the SmartKey checked at a qualified specialist workshop. You can no longer lock
or unlock the vehicle
using KEYLESS-GO. There is interference from a powerful source of radio waves.
X 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 000Cor000B button. There is a malfunction with KEYLESS-GO.
X 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 000Cor000B button.
X Have KEYLESS-GO checked at a qualified specialist workshop.
If this does not work:
X Check the SmartKey battery (Y page 83) and replace it if
necessary (Y page 83).
X Lock (Y page 88) or unlock (Y page 88) the vehicle using
the mechanical key. You have lost a
SmartKey. X
Have the SmartKey deactivated at a qualified specialist
workshop.
X Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. SmartKey
85Opening and closing Z

Problem Possible causes/consequences and
0001 Solutions
The engine cannot be
started using the
SmartKey. The on-board voltage is too low.
X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 388).
or
X Jump-start the vehicle (Y page 389).
or
X Consult a qualified specialist workshop. The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle. Ad
oor is open. Therefore, the SmartKey cannot be detected as
easily.
X Close the door and try to start the vehicle again. There is interference from a powerful source of radio waves.
X
Start your vehicle with the SmartKey in the ignition lock. Doors
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shift the automatic transmission out of
parking position P.
R starting the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children. G
WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle. G
WARNING
If objects, luggage or loads are not secured or
not secured sufficiently, they could slip, tip
over or be flung around and thereby hit vehicle
occupants. There is a risk of injury,
particularly in the event of sudden braking or
a sudden change in direction.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping before the
journey.
You should preferably place luggage or loads
in the cargo compartment. Observe the
loading guidelines (Y page 332).86
DoorsOpening and closing

Problems with the seat ventilation
Problem Possible causes/consequences and
0001 Solutions
The seat ventilation has
switched off
prematurely or cannot
be switched on. The on-board voltage is too low because too many electrical
consumers are switched on.
X
Switch off electrical consumers that you do not need, such as
the rear window defroster or interior lighting.
Once the battery is sufficiently charged, the seat ventilation will
switch back on automatically. Steering wheel
Important safety notes
G
WARNING
You could lose control of your vehicle if you
do the following while driving:
R adjust the driver's seat, head restraint,
steering wheel or mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint,
steering wheel and mirror and fasten your
seat belt before starting the engine. G
WARNING
Children could injure themselves if they
adjust the steering wheel. There is a risk of
injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle. Adjusting the steering wheel
manually
G
WARNING
If the steering wheel is unlocked while the
vehicle is in motion, it could change position
unexpectedly. This could cause you to lose
control of the vehicle. There is a risk of an
accident. Before starting off, make sure the steering
wheel is locked. Never unlock the steering
wheel while the vehicle is in motion.
0002
Release lever
0003 To adjust the steering wheel height
0023 To adjust the steering wheel position
(fore-and-aft adjustment)
X Push release lever 0002down completely.
The steering column is unlocked.
X Adjust the steering wheel to the desired
position.
X Push release lever 0002up completely.
The steering column is locked.
X Check 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 wheel
111Seats, steering wheel and mirrors Z

Display messages Possible causes/consequences and
0001 Solutions
0001
Replace
Key Battery The batteries of the KEYLESS-GO key are discharged.
X Change the batteries ( Ypage 83). 0001
Don't Forget Your
Key This display message is displayed fo
ramaximum of 60 seconds
and is simply a reminder.
You have opened the driver's door with the engine switched off.
The KEYLESS-GO key is not in the ignition lock.
X Remember to take the KEYLESS-GO key with you when you
leave the vehicle. 0001
Key Not Detected
(red display message) The KEYLESS-GO key is not in the vehicle.
Aw
arning tone also sounds.
If the engine is switched off, you can no longer loc kthe vehicle
centrally or start the engine.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 179).
X Locate 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.
Aw
arning tone also sounds.
X Pull ove rand stop the vehicle safely as soo nas possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 179).
X Operate the vehicle with the SmartKey in the ignition lock. 0001
Key Not Detected
(white display
message) The KEYLESS-GO key cannot be detected at present.
X
Change the location of the SmartKey with the KEYLESS-GO
functions in the vehicle.
If the KEYLESS-GO key is still not detected:
X Operate the vehicle with the SmartKey in the ignition lock. 0001
Key Detected in
Vehicle The KEYLESS-GO key has been detected inside the vehicle during
locking.
X
Remove the KEYLESS-GO key from the vehicle. Display messages
315On-board computer and displays Z