
KEYLESS-GO start function
General notes Bear in mind that the engine can be started by
any of the vehicle occupants if there is a Smart-
Key in the vehicle (Y page 137). Changing the settings of the locking
system
You can change the settings of the locking sys-
tem. This means that only the driver's door and
the fuel filler flap are unlocked when the vehicle is unlocked. This is useful if you frequently travelalone.
X To change the setting: press and hold down
the 0036 and0037 buttons simultaneously
for about six seconds until the battery indica-
tor lamp flashes twice (Y page 80).
If the setting of the locking system is changed
within the signal range of the vehicle, pressing
the 0037 or0036 button:
R locks or
R unlocks the vehicle
The SmartKey now functions as follows:
X To unlock: press the0036button once.
X To unlock centrally: press the0036button
twice.
X To lock centrally: press the0037button.
The KEYLESS-GO function is changed as fol-
lows:
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 78).
X To restore the factory settings: press and
hold down the 0036and0037 buttons simul-
taneously for approximately six seconds until
the battery check lamp flashes twice
(Y page 80). Mechanical key
General notes If the vehicle can no longer be locked or
unlocked with the SmartKey or with KEYLESS-
GO, use the mechanical key.
If you use the mechanical key to unlock and
open the driver's door, the anti-theft alarm sys-
tem will be triggered. Switch off the alarm
(Y page 75).
If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked auto-
matically.
X To unlock the fuel filler flap: insert the
SmartKey into the ignition lock.
Removing the mechanical key X
Push release catch 0043in the direction of the
arrow and at the same time remove mechan- ical key 0044from the SmartKey.
For further information about:
R Unlocking the driver's door (Y page 84)
R Unlocking the cargo compartment
(Y page 88)
R Locking the vehicle (Y page 84)
Inserting the mechanical key X
Push mechanical key 0044completely into the
SmartKey until it engages and release
catch 0043is back in its basic position. SmartKey
79Opening and closing Z

Problem
Possible causes/consequences and
0050
0050Solutions There is interference from a powerful source of radio waves.
X Unlock (Y page 84) or lock (Y page 84) the vehicle using the
mechanical key. KEYLESS-GO is malfunctioning.
X Lock/unlock the vehicle using the remote control function of the
SmartKey.
X Have the vehicle and SmartKey checked at a qualified specialist
workshop.
If the vehicle can also not be locked/unlocked using the remote con-
trol function:
X Unlock (Y page 84) or lock (Y page 84) the vehicle using the
mechanical key.
X Have the vehicle and SmartKey checked at a qualified specialist
workshop. The engine cannot be
started using the Smart-
Key. 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 342).
or X Jump-start the vehicle (Y page 343).
or X Consult a qualified specialist workshop. The engine cannot be
started using the Start/
Stop button. The Smart-
Key is in the vehicle. The vehicle is locked.
X Unlock the vehicle and try to start the vehicle again. The SmartKey battery is discharged or nearly discharged.
X Check the SmartKey battery (Y page 80) and replace it if necessary
(Y page 80).
If this does not work: X Start your vehicle with the SmartKey in the ignition lock. There is interference from a powerful source of radio waves.
X Start your vehicle with the SmartKey in the ignition lock. You have lost a Smart-
Key. 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. 82
SmartKeyOpening and closing

Problems with the seat heating or seat ventilation
Problem
Possible causes/consequences and
0050
0050Solutions The seat heating or seat
ventilation has switched
off prematurely or can-
not be switched on. The on-board voltage is too low because too many electrical consum-
ers 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 heating or 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, steer-
ing 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.
The electrically adjustable steering wheel can
still be adjusted when there is no SmartKey in
the ignition lock. Adjusting the steering wheel man-
ually
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. 0043
Release lever
0044 Adjusts the steering wheel height
0087 Adjusts the steering wheel position (fore-
and-aft adjustment)
X Push release lever 0043down completely.
The steering column is unlocked.
X Adjust the steering wheel to the desired posi-
tion.
X Push release lever 0043up 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
103Seats, steering wheel and mirrors Z

Problems with the windshield wipers
Problem
Possible causes/consequences and
0050
0050Solutions The windshield wipers
are jammed. Leaves or snow, for example, may be obstructing the windshield wiper
movement. The wiper motor has been deactivated.
X For safety reasons, you should remove the SmartKey from the igni-
tion lock.
or X Switch off the engine using the Start/Stop button and open the
driver's door.
X Remove the cause of the obstruction.
X Switch the windshield wipers back on. The windshield wipers
fail completely. The windshield wiper drive is malfunctioning.
X Select another wiper speed on the combination switch.
X Have the windshield wipers checked at a qualified specialist work-
shop. Windshield wipers
121Lights and windshield wipers Z

!
Do not warm up the engine while stationary.
Pull away immediately. Avoid high engine
speeds and full throttle until the engine has
reached its operating temperature.
In vehicles with automatic transmission,
engage positions P and R only when the vehi-
cle is stationary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery roads.
You could otherwise damage the drive train.
! Mercedes-AMG vehicles:
at low engine oil
temperatures below 68 ‡ (+20 †), the max-
imum engine speed is restricted in order to
protect the engine. To protect the engine and
maintain smooth engine operation, avoid driv-
ing at full throttle when the engine is cold.
Plug-in hybrid: be sure to read the separate
Operator's Manual. Otherwise, you may not rec-
ognize dangers. Key positions
SmartKey 005A
To remove the SmartKey
0047 Power supply for some consumers, such as
the windshield wipers
0048 Ignition (power supply for all consumers)
and drive position
0049 To start the engine
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light
up. Further information on situations where an
indicator lamp either fails to go out after starting the engine or lights up while driving
(Y page 276).
If the SmartKey is in position 0092in the ignition
lock for a longer period, it can no longer be
turned in the ignition lock. The steering is then locked. To unlock, remove the SmartKey and
reinsert it into the ignition lock.
The steering is locked when you remove the
SmartKey from the ignition lock.
X Remove the SmartKey when the engine is
switched off.
The starter battery could otherwise be dis-
charged.
If you cannot turn the SmartKey in the ignition
lock, the starter battery may not be charged
sufficiently.
X Check the starter battery and charge it if nec-
essary (Y page 342).
or
X Jump-start the vehicle (Y page 343).
i The SmartKey can be turned in the ignition
lock even if it is not the correct SmartKey for
the vehicle. The ignition is not switched on.
The engine cannot be started.
KEYLESS-GO General notes
Vehicles with KEYLESS-GO are equipped with a
SmartKey featuring an integrated KEYLESS-GO
function and a detachable Start/Stop button.
A check which periodically establishes a radio
connection between the vehicle and the Smart-
Key determines whether a valid SmartKey is in
the vehicle. This occurs, for example, when
starting the engine.
When you insert the Start/Stop button into the ignition lock, the system needs approximately
two seconds recognition time. You can then usethe Start/Stop button.
Pressing the Start/Stop button several times in
succession corresponds to the different Smart-
Key positions in the ignition lock. This is only the
case if you are not depressing the brake pedal.
If you depress the brake pedal and press the
Start/Stop button, the engine starts immedi-
ately.
To start the vehicle without actively using the
SmartKey:
R the Start/Stop button must be inserted in the
ignition lock
R the SmartKey must be in the vehicle
R the vehicle must not be locked with the
SmartKey or KEYLESS-GO (Y page 78). Driving
135Driving and parking Z

Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shifting the automatic transmission out of
park position P
R Start 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
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation. G
WARNING
Flammable materials introduced through
environmental influence or by animals can
ignite if in contact with the exhaust system or parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
General notes Vehicles with a gasoline engine:
the catalytic
converter is preheated for up to 30 seconds
after a cold start. The sound of the engine may
change during this time.
Automatic transmission X
Shift the transmission to position 005D
(Y page 144).
The transmission position indicator on the
multifunction display shows 005D
(Y page 145). i
You can start the engine in transmission
position 005Dand 005C.
Starting procedure with the SmartKey X
To start a diesel engine: turn the SmartKey
to position 0048in the ignition lock
(Y page 135).
The 0028 indicator lamp on the instrument
cluster lights up.
X Turn the SmartKey to position 0049in the igni-
tion lock (Y page 135) and release it as soon
as the engine is running.
i Vehicles with a diesel engine:
you can
start the engine without preglow if the engine
is warm.
Using KEYLESS-GO to start the engine The Start/Stop button can be used to start the
vehicle without inserting the SmartKey into the
ignition lock. The Start/Stop button must be
inserted in the ignition lock and the SmartKey
must be in the vehicle. This mode for starting the engine operates independently of the ECO
start/stop automatic engine start function.
X Depress the brake pedal and keep it
depressed.
X Press the Start/Stop button once
(Y page 135).
Vehicles with a gasoline engine: the engine
starts.
Vehicles with a diesel engine: preglow is
activated and the engine starts.
Starting procedure via smartphone Observe the important safety notes on starting
the engine (Y
page 136).
You can also start your engine via your smart-
phone from outside the vehicle. In this case, the previously selected climate control setting is
activated. In this way you can cool or heat the
interior of the vehicle before starting the jour-
ney.
Only start the engine via your smartphone if it is
safe to start and run the engine where your vehi-
cle is parked.
Observe the legal stipulations in the area where your vehicle is parked. Engine start via smart-
phone may be limited to certain countries or
regions. Driving
137Driving an d parking Z

Problem
Possible causes/consequences and
0050
0050Solutions Vehicles with a gasoline
engine:
The engine is not running
smoothly and is misfir-
ing. There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
X Only depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic converter
and damage it.
X Have the cause rectified immediately at a qualified specialist work-
shop. The coolant temperature
gage shows a value
above 248 ‡ (120 †). The coolant level is too low. The coolant is too hot and the engine is no
longer being cooled sufficiently.
X Stop as soon as possible and allow the engine and the coolant to
cool down.
X Check the coolant level (Y page 324). Observe the warning notes
as you do so and add coolant if necessary. DYNAMIC SELECT controller
Plug-in hybrid: observe the notes on the
DYNAMIC SELECT controller in the separate
operating instructions.
Use the DYNAMIC SELECT controller to change the drive program. Depending on the drive pro-
gram selected the following vehicle character-
istics will change:
R the drive (engine and transmission manage-
ment)
R the transmission
R the suspension
R the steering
R the availability of the ECO start/stop function
Each time you start the engine with the Smart-
Key or the Start/Stop button, the Comfortdrive
program is activated. For further information
about starting the engine, see (Y page 136).
The Comfort drive program is recommended in
city traffic and stop/start traffic situations. X
All vehicles (except Mercedes-AMG vehi-
cles):
turn DYNAMIC SELECT controller 0043as
many times as necessary until the desired
drive program is selected.
The selected drive program appears in the
multifunction display. After five seconds, this information disappears from the display.
In addition, the current drive program settings
are displayed in the multimedia system dis-
play.
Drive programs available (all vehicles
except Mercedes-AMG vehicles): Individual
Individual settings
Sport
Sporty driving characteris-
tics
Comfort
Comfortable and economi-
cal driving characteristics 142
DYNAMIC SELECT controllerDriving and parking

With the SmartKey:
X Switch on the ignition.
X Depress the brake pedal and keep it
depressed.
X Shift to neutral 005C.
X Release the brake pedal.
X Release the electric parking brake.
X Switch off the ignition and leave the SmartKey
in the ignition lock.
With the Start/Stop button: X Remove the Start/Stop button from the igni-
tion lock.
X Insert the SmartKey into the ignition lock.
X Switch on the ignition.
X Depress the brake pedal and keep it
depressed.
X Shift to neutral 005C.
X Release the brake pedal.
X Release the electric parking brake.
X Switch off the ignition and leave the SmartKey
in the ignition lock.
Engaging drive position D X
If the transmission is in position 005Eor005C:
push the DIRECT SELECT lever down past the first point of resistance.
X If the transmission is in position 005D: depress
the brake pedal and push the DIRECT SELECT lever down past the first point of resistance. Transmission position and drive pro-
gram display
The current transmission position and drive pro-
gram appear in the multifunction display. 0043
Transmission position
0044 Gear
0087 Drive program The arrows in the transmission position display
show how and into which transmission positions
you can shift using the DIRECT SELECT lever.
If the transmission position display on the mul-
tifunction display is not working, you should pull away carefully to check whether the desired
transmission position is engaged. Ideally, you
should select transmission position 005B. Transmission positions
0045 Park position
Only shift the transmission into posi-
tion 005D(Ypage 156) when the vehi-
cle is stationary. The parking lock
should not be used as a brake when
parking. Always apply the electronic
parking brake in addition to the park-
ing lock in order to secure the vehi-
cle.
In the event of a malfunction of the
vehicle's electronics, the transmis-
sion may lock in position 005D. Have
the vehicle electronics checked
immediately at a qualified specialist
workshop.
Park position 005Dis automatically
engaged if:
R you switch off the engine using the
SmartKey and remove the Smart-
Key
R you switch off the engine using the
SmartKey or using the Start/Stop
button and open the driver's door
or front-passenger door
R you open the driver's door when
the vehicle is stationary or when
driving at a very low speed and the
transmission is in position 005Bor
005E 0046 Reverse gear
Shift the transmission into position
005E only when the vehicle is station-
ary. Automatic transmission
145Driving and parking Z