2017 MERCEDES-BENZ CLA change key battery

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 travel
on your own. X
To change the setting: press and hold the
6 and 7 buttons simultaneously for
approximately six seconds until the battery
indicator lamp flashes twice ( Y
page 72).
If the setting of the locking system is changed
within the signal range of the vehicle, pressing
the 7 or 6 button:R
locks or R
unlocks the vehicle
The SmartKey now functions as follows: X
To unlock: press the 6 button once.X
To unlock centrally: press the 6 button
twice. X
To lock centrally: press the 7 button.
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. X
To restore the factory settings: press and
hold the 6 and 7 buttons simultane-
ously for approximately six seconds until the
batter y check lamp flashes twice
( Y
page 72).
Mechanical key
General notes
If the vehicle can no longer be locked or
unlocked with the SmartKey or KEYLESS-GO,
use the mechanical key.
If you use the mechanical key to unlock and
open the driver's door or the trunk lid, the anti-
theft alarm system will be triggered ( Y
page 67). There are several ways to turn off the alarm: X
To deactivate the alarm with the key: press
the 6 or 7 button on the key.
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 vehi-
cle.
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 C in the direction of the
arrow and at the same time remove mechan-
ical key D from the SmartKey.
For further information about: R
Unlocking the driver's door ( Y
page 76)R
Unlocking the trunk ( Y
page 80)R
Locking the vehicle ( Y
page 76)
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 71
Opening and closing Z

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 guide-
lines must be observed during disposal. In Cal-
ifornia, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/index.cfm .
Mercedes-Benz recommends that you have the
battery replaced at a qualified specialist work-
shop.
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 72).
i If the SmartKey battery is checked within
the signal reception range of the vehicle,
pressing the 7 or 6 button:R
locks or R
unlocks the vehicle
i You can get a battery at any qualified spe-
cialist workshop. Replacing the battery You require a CR 2025 3 V cell battery. X
Take the mechanical key out of the SmartKey
( Y
page 71).
X
Press mechanical key D into the opening in
the SmartKey in the direction of the arrow
until battery tray cover C opens. When doing
so, do not hold cover C shut.X
Remove battery tray cover C .
X
Repeatedly tap the SmartKey against your
palm until battery

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 con-
trol function: X
Unlock ( Y
page 76) or lock ( Y
page 76) 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 273).
or X
Jump-start the vehicle ( Y
page 273).
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 72) and replace it if necessary
( Y
page 72).
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.74
SmartKey
Opening and closing

Problems with the seat heating Problem
Possible causes/consequences and P Solutions
The seat heating has
switched off prematurely
or cannot 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 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.
Adjusting the steering wheel
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. C
Release lever D
Adjusts the steering wheel height

Folding the exterior mirrors in or out
electrically X
Turn th e SmartKey to position 1 or 2 in th e
ignition loc k ( Y
page 121).X
Briefly press C .
Both exterio r mirror s fol d in or out .
i Mak e sure that th e exterio r mirror s are
always folded out fully while driving . They
could otherwise vibrate .
i If you are driving faste r than 30 mph
(47 km/h), you can no longer fol d in th e exte -
rio r mirrors.
Resetting the exterior mirrors If th e battery has been disconnected or com-
pletely discharged, th e exterio r mirror s must be
reset . The exterio r mirror s will otherwise no t
fol d in when you select th e "Fold in mirror s when
locking" function in th e on-board computer
( Y
page 185). X
Turn th e SmartKey to position 1 in th e ignition
loc k ( Y
page 121).X
Briefly press C .
Folding the exterior mirrors in or out
automatically If th e "Fold in mirror s when locking" function is
activated in th e on-board computer
( Y
page 185): R
th e exterio r mirror s fol d in automatically as
soo n as you loc k th e vehicl e from th e outside .R
th e exterio r mirror s fol d out again automati-
call y as soo n as you unlock th e vehicl e and
then open th e driver' s or front-passenger
door . i If th e exterio r mirror s have been folded in
manually, they do no t fol d out .
Exterior mirror pushed out of position If an exterio r mirror has been pushed out of
position , procee d as follows :X
Vehicles without electricall y folding exte-
rior mirrors : mov e th e exterio r mirror int o
th e correct position manually. X
Vehicles with electricall y folding exterior
mirrors : press and hold mirror-foldin g butto n
( Y
page 96 )u ntil you hear the mirror click into
place.
The mirror housing is engaged again and you
can adjust the exterior mirrors as usual
( Y
page 95).
Automatic anti-glare mirrors
G WARNING
Electrolyte may escape if the glass in an auto-
matic anti-glare mirror breaks. The electrolyte
is harmful and causes irritation. It must not
come into contact with your skin, eyes, res-
piratory organs or clothing or be swallowed.
There is a risk of injury.
If you come into contact with the electrolyte,
observe the following: R
Rinse off the electrolyte from your skin
immediately with water. R
Immediately rinse the electrolyte out of
your eyes thoroughly with clean water. R
If the electrolyte is swallowed, immediately
rinse your mouth out thoroughly. Do not
induce vomiting. R
If electrolyte comes into contact with your
skin or hair or is swallowed, seek medical
attention immediately. R
Immediately change out of clothing which
has come into contact with electrolyte. R
If an allergic reaction occurs, seek medical
attention immediately.
The "Automatic anti-glare mirrors" function is
only available if the vehicle is equipped with the
"Mirrors package".96
Mirrors
Seats, steering wheel an d mirrors

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 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 129).
The transmission position display in the mul-
tifunction display shows P ( Y
page 129).
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 ignition
lock and release it as soon as the engine is
running ( Y
page 121).
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 automatic engine start func-
tion.
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 121).
The engine starts.
Starting procedure via smartphone Observe the important safety notes on starting
the engine ( Y
page 122).
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.
You can execute a maximum of two consecutive
starting attempts via your smartphone. If you
insert the SmartKey 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 SmartKey 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- Driving 123
Driving and parking Z

Problem
Possible causes/consequences and P Solutions
The engine does not
start. You cannot hear
the starter motor. The on-board voltage is too low because the battery is too weak or
discharged. X
Jump-start the vehicle ( Y
page 273).
If the engine does not start despite attempts to jump-start it: X
Consult a qualified specialist workshop.
The starter motor was exposed to a thermal load that was too high. X
Allow the starter motor to cool down for approximately two minutes. X
Try to start the engine again.
If the engine still does not start: X
Consult a qualified specialist workshop.
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
gauge shows a value
above 248 ‡ (120 †).
The coolant warning
lamp may also be on and
a warning tone may
sound. 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 257). Observe the warning notes
as you do so and add coolant if necessary.
DYNAMIC SELECT button (all vehicles
except Mercedes-AMG vehicles) Use the DYNAMIC SELECT button to change the
drive program. Depending on the drive program
selected the following vehicle characteristics
will change: R
the drive (engine and transmission manage-
ment) R
the suspension (vehicles with damping sys-
tem or AMG adaptive sport suspension sys-
tem) R
the steering. R
the availability of the ECO start/stop function R
the climate control
Each time you start the engine with the Smart-
Key or the Start/Stop button, drive program C is
activated. For further information about starting
the engine, see ( Y
page 122). X
Press DYNAMIC SELECT button C as many
times as necessary until the desired drive
program is selected.
The selected drive program appears in the
multifunction display. After five seconds the
display goes out and the status icon of the
selected drive program appears.DYNAMIC SELECT button (all vehicles except Mercedes-AMG vehicles) 127
Driving and parking Z