2016 MERCEDES-BENZ CLA start stop button

Useful information
i This Operator's Manual describes all
models and all standard and optional equip-
ment 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 Read the information on qualified special-
ist workshops ( Y
page 25).
SmartKey
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
shifting the automatic transmission out of
park position PR
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
If you attach heavy or large objects to the
SmartKey, the SmartKey could be uninten-
tionally turned in the ignition lock. This could
cause the engine to be switched off. There is a
risk of an accident. Do not attach any heavy or large objects to the
SmartKey. Remove any bulky key rings before
inserting the SmartKey into the ignition lock.
! Keep the SmartKey away from strong
magnetic fields. Otherwise, the remote
control function could be affected.
Strong magnetic fields can occur in the
vicinity of powerful electrical installations.
Do not keep the SmartKey: R
with electronic devices, e.g. a mobile
phone or another SmartKey. R
with metallic objects, e.g. coins or metal
foil. R
inside metallic objects, e.g. a metal case.
Vehicles with KEYLESS-GO start function:
do not keep the SmartKey in the cargo com-
partment. Otherwise, the SmartKey may not
be detected, e.g. when starting the engine
using the Start/Stop button.
SmartKey functions
C
7 To lock the vehicleD
T To open the trunk lid

X
Insert the SmartKey into the ignition lock.
or X
To deactivate the alarm with KEYLESS-
GO: press the Start/Stop button in the igni-
tion 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
X
Push release catch C in the direction of
the arrow and at the same time remove
mechanical key D from the SmartKey.
For further information about: R
unlocking the driver's door ( Y
page 85)R
unlocking the trunk ( Y
page 87)R
locking the vehicle ( Y
page 85)
Inserting the mechanical key X
Push mechanical key D completely into
the SmartKey until it engages and release
catch C is back in its basic position. SmartKey battery
Important safety notes
G WARNING
Batteries contain toxic and corrosive substan-
ces. 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.
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 .
Mercedes-Benz recommends that you have
the battery replaced at a qualified specialist
workshop.
Checking the battery
X
Press the 7 or 6 button.
The battery is working properly if battery
check lamp C lights up briefly.
The battery is discharged if battery check
lamp C does not light up briefly. X
Change the battery ( Y
page 80).SmartKey 79
Opening and closing Z

Problem
Possible causes/consequences and P Solutions
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
control function: X
Unlock ( Y
page 85) or lock ( Y
page 85) 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
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 317).
or X
Jump-start the vehicle ( Y
page 319).
or X
Consult a qualified specialist workshop.
The engine cannot be
started using the Start/
Stop button. The
SmartKey is in the vehi-
cle. 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 79) and replace it if nec-
essary ( 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.82
SmartKey
Opening and closing

R
Use the residual heat function if you want to
heat or ventilate the vehicle interior when
the ignition is switched off. The residual
heat function can only be activated or deac-
tivated with the ignition switched off. R
If you change the settings of the climate
control system, the climate status display
appears for approximately three seconds
at the bottom of the screen in the Audio/
COMAND display (see separate operating
instructions). You will see the current set-
tings of the various climate control func-
tions.
DYNAMIC SELECT button (except
Mercedes-AMG vehicles) You can choose between various drive pro-
grams with the DYNAMIC SELECT button
( Y
page 155).
If you have selected drive program E :R
when heating, the electrical heater booster
is deactivated and in the warming-up phase
heat output is reduced R
the rear window defroster running time is
reduced
Depending on the configuration, the climate
settings can also be influenced in drive pro-
gram I .
If you have selected drive program C or S , the
climate settings are not affected.
ECO start/stop function
During automatic engine switch-off, the cli-
mate control system only operates at a
reduced capacity. If you require the full cli-
mate control output, you can switch off the
ECO start/stop function by pressing the ECO
button ( Y
page 153). Operating the climate control sys-
tems
Activating/deactivating climate con-
trol
General notes When the climate control is switched off, the
air supply and air circulation are also
switched off. The windows could fog up.
Therefore, switch off climate control only
briefly
Air-conditioning system X
Turn the SmartKey to position 2 in the igni-
tion lock ( Y
page 147). X
To switch on: turn control

G WARNING
Unsuitable footwear can hinder correct usage
of the pedals, e.g.: R
shoes with thick soles R
shoes with high heels R
slippers
There is a risk of an accident.
Wear suitable footwear to ensure correct
usage of the pedals.
G WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect,
for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving.
G WARNING
If the parking brake has not been fully
released when driving, the parking brake can: R
overheat and cause a fire R
lose its hold function.
There is a risk of fire and an accident. Release
the parking brake fully before driving off.
! Do not warm up the engine with the vehi-
cle stationary. Drive off immediately. Avoid
high engine speeds and driving at full throt-
tle until the engine has reached its operat-
ing temperature.
Only shift the automatic transmission to
the desired drive position when the vehicle
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: avoid full-load
operation and engine speeds greater than
5000 rpm when the engine is cold. This helps to protect the engine and avoids
uncomfortable driving.
SmartKey positions
SmartKey
Z
To remove the SmartKey
(shift the transmission to position P )G
Power supply for some consumers, such
as the windshield wipers H
Ignition (power supply for all consumers)
and drive position I
To start the engine
i The SmartKey can be turned in the igni-
tion lock even if it is not the correct Smart-
Key for the vehicle. The ignition is not
switched on. The engine cannot be started.
Start/Stop button
General notes
Vehicles with KEYLESS-GO are equipped with
SmartKeys featuring the integrated KEYLESS-
GO function and a detachable Start/Stop but-
ton.
A check which periodically establishes a radio
connection between the vehicle and the
SmartKey determines whether a valid Smart-
Key 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 approx-
imately two seconds recognition time. You
can then use the Start/Stop button. Driving 147
Driving and parking Z

Pressing the Start/Stop button several times
in succession corresponds to the different
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 77).
Do not keep the KEYLESS-GO key: R
with electronic devices, e.g. a mobile
phone or another SmartKey. R
with metallic objects, e.g. coins or metal
foil. R
inside metallic objects, e.g. a metal case.
This can affect the functionality of KEYLESS-
GO.
If you lock the vehicle with the SmartKey's
remote control or with KEYLESS-GO, after a
short time: R
you will not be able to switch on the ignition
with the Start/Stop button. R
you will not be able to start the engine with
the Start/Stop button until the vehicle is
unlocked again.
If you lock the vehicle centrally using the but-
ton on the front door ( Y
page 84), you can
continue to start the engine with the Start/
Stop button.
The engine can be switched off while the vehi-
cle is in motion by pressing and holding the
Start/Stop button for three seconds. This
function operates independently of the ECO
start/stop automatic engine switch-off func-
tion. Key positions with the Start/Stop button
C
Start/Stop button D
Ignition lock
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 260).
If Start/Stop button C has not yet been
pressed, this corresponds to the key being
removed from the ignition. X
To switch on the power supply: press
Start/Stop button C once.
The power supply is switched on. You can
now activate the windshield wipers, for
example.
The power supply is switched off again if: R
the driver's door is opened and R
you press Start/Stop button C twice when
in this position X
To switch on the ignition: press Start/
Stop button C twice.
The ignition is switched on.
If you press Start/Stop button C once
when in this position, the ignition is
switched off again.
Removing the Start/Stop button
You can remove the Start/Stop button from
the ignition lock and start the vehicle as nor-
mal using the SmartKey.148
Driving
Driving and parking

You can only switch between Start/Stop but-
ton mode and SmartKey operation when the
vehicle is stationary.
You must also engage park position P .X
Remove Start/Stop button C from ignition
lock D .
You do not have to remove the Start/Stop
button from the ignition lock when you leave
the vehicle. You should, however, always take
the SmartKey with you when leaving the vehi-
cle. As long as the SmartKey is in the vehicle: R
the vehicle can be started using the Start/
Stop button R
the electrically powered equipment can be
operated
Starting the engine
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
shifting the automatic transmission out of
park position PR
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.
! Do not depress the accelerator when
starting the engine.
General notes During a cold start, the engine runs at higher
speeds to enable the catalytic converter to
reach its operating temperature. The sound of
the engine may change during this time.
Automatic transmission X
Shift the transmission to position P
( Y
page 157).
The transmission position display in the
multifunction display shows
P ( Y
page 157).
i You can start the engine in transmission
position P and N .
Starting procedure with the SmartKey
To start the engine using the SmartKey
instead of the Start/Stop button, pull the
Start/Stop button out of the ignition lock. X
Turn the SmartKey to position 3 in the igni-
tion lock and release it as soon as the
engine is running ( Y
page 147).Driving 149
Driving and parking Z

Starting procedure with the Start/Stop
button The Start/Stop button can be used to start
the vehicle manually 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 auto-
matic engine start function.
You can start the engine if a valid SmartKey is
in the vehicle. Switch off the engine and
always take the SmartKey with you when
leaving the vehicle, even if you only leave it for
a short time. Pay attention to the important
safety notes. X
Depress the brake pedal and keep it
depressed. X
Press the Start/Stop button once
( Y
page 147).
The engine starts.
Starting procedure via smartphone
Observe the important safety notes on start-
ing the engine ( Y
page 149).
You can also start your engine via your smart-
phone from outside the vehicle. In this case,
the previously selected climate control set-
ting is activated. In this way you can cool or
heat the interior of the vehicle before starting
the journey.
Only start the engine via your smartphone if it
is safe to start and run the engine where your
vehicle is parked.
Observe the legal stipulations in the area
where your vehicle is parked. Engine start via
smartphone may be limited to certain coun-
tries or regions.
You can execute a maximum of two consec-
utive starting attempts via your smartphone.
If you insert the key into the ignition lock, you
can carry out two more starting attempts.
Once you have started the engine, you can
switch the engine off via your smartphone at
any time. You can only start the engine via your smart-
phone if: R
the key is in the ignition lock R
park position P is selected R
the accelerator pedal is not depressed R
the anti-theft alarm system is not activated R
the panic alarm is not activated R
the hazard warning lamps are switched off R
the hood is closed. R
the doors are closed and locked R
the windows and sliding sunroof are closed
Also make sure that: R
the fuel tank is sufficiently filled R
the starter battery is sufficiently charged
G WARNING
Limbs could be crushed or trapped if the
engine is started unintentionally during ser-
vice or maintenance work. There is a risk of
injury.
Always secure the engine against uninten-
tional starting before carrying out mainte-
nance or repair work.
Make sure that the engine cannot be started
via your smartphone before carrying out
maintenance or repairs. You can prevent an
engine start via your smartphone, for exam-
ple, if you: R
switch on the hazard warning lamps R
do not lock the doors R
open the hood.
Pulling away
General notes
G WARNING
If the engine speed is above the idling speed
and you engage transmission position D or R ,
the vehicle could pull away suddenly. There is
a risk of an accident.150
Driving
Driving and parking