2018 MERCEDES-BENZ CLA battery

Problems with the SmartKey Problem
Possible causes/consequences and P Solutions
You cannot lock or
unlock the vehicle using
the SmartKey. The SmartKey battery is discharged or nearly discharged. X
Vehicles without KEYLESS-GO or KEYLESS-GO star tf unction:
try again to lock/unlock the vehicle using the remote control func-
tion of the SmartKey. Point the tip of the SmartKey at the driver's
door handle from close range and press the 6 or 7 button.
If this does not work: X
Check the SmartKey battery ( Y
page 73) and replace it if necessary
( Y
page 73). X
Unlock ( Y
page 77) or lock ( Y
page 77) the vehicle using the
mechanical key.
There is interference from ap owerful source of radio waves.X
Vehicles without KEYLESS-GO or KEYLESS-GO star tf unction:
try again to lock/unlock the vehicle using the remote control func-
tion of the SmartKey. Point the tip of the SmartKey at the driver's
door handle from close range and press the 6 or 7 button.
If this does not work: X
Unlock ( Y
page 77) or lock ( Y
page 77) the vehicle using the
mechanical key.
The SmartKey is faulty. X
Unlock ( Y
page 77) or lock ( Y
page 77) the vehicle using the
mechanical key. X
Have the SmartKey checked at aq ualified specialist workshop.
You can no longer lock or
unlock the vehicle using
KEYLESS-GO. The SmartKey battery is discharged or nearly discharged. X
Check the SmartKey battery ( Y
page 73) and replace it if necessary
( Y
page 73).
If this does not work: X
Unlock ( Y
page 77) or lock ( Y
page 77) the vehicle using the
mechanical key.
There is interference from ap owerful source of radio waves.X
Unlock ( Y
page 77) or lock ( Y
page 77) the vehicle using the
mechanical key.74
SmartKey
Opening and closing

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 aq ualified specialist
workshop.
If the vehicle can also not be locked/unlocked using the remote con-
trol function: X
Unlock ( Y
page 77) or lock ( Y
page 77) the vehicle using the
mechanical key. X
Have the vehicle and SmartKey checked at aq ualified 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 278).
or X
Jump-start the vehicle ( Y
page 278).
or X
Consult aq ualified 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 73) and replace it if necessary
( Y
page 73).
If this does not work: X
Start your vehicle with the SmartKey in the ignition lock.
There is interference from ap owerful source of radio waves.X
Start your vehicle with the SmartKey in the ignition lock.
You have lost aS mart-
Key. X
Have the SmartKey deactivated at aq ualified 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 75
Opening and closing Z

Door s
Important safet yn otes
G WARNING
If children are lef tu nsupervised in th ev ehicle,
they could: R
ope nt he doors ,t hu se nd angerin go th er
people or road users. R
get out and disrup tt ra ffic .R
operat et he vehicle' se quipment.
Additionally, children could set th ev ehicle in
motion if, fo re xa mple, they:R
release th ep arking brake .R
shiftin gt he automatic transmissio no ut of
par kp osition PR
Start th ee ng ine.
There is ar is kofana cciden ta nd injury.
Whe nl eavin gt he vehicle, always take th e
SmartKey wit hy ou and loc kt he vehicle. Never
leav ec hi ldren or animals unattended in th e
vehicle. Always keep th eS ma rtKey out of
reach of children .
You should preferably plac el uggage or load si n
th ec argo compartment. Observ et he loadin g
guidelines ( Y
page 237).
Unlockin ga nd opening doors from
th ei nside
! The sid ew indows will no to pen/close if th e
battery is discharged or if th es id ew indows
hav ei ce du p. It will then no tbep ossible to
close th ed oor. Do no ta ttemp ttof orce th e
doo rc lo sed. You could otherwise damage th e
doo rort he sid ew indow.
Whe nad oo riso pened, th es id ew indow on that
sid eo pens slightly. Whe nt he doo risc lo sed, th e
sid ew indow close sa gain . X
To unlock an do pe naf ro nt door: pull doo r
handle D .
If th ed oo risl ocked, locking knob C pop su p.
The doo risu nlocke da nd opens .X
To unlock ar ea rd oor: pull up locking
knob C .
The doo risu nlocke da nd can be opened.X
To ope nar ea rd oor: pull doo rh andle D .
You can ope nad oo rf ro mi ns id et he vehicle
eve nifith as bee nl ocked. You can only ope nt he
rea rd oors from insid et he vehicle if they are no t
secure dbyt he child-proof locks ( Y
page 60).
If th ev ehicle has previously bee nl ocke dw it h
th eS ma rtKey from th eo utside, opening ad oo r
from th ei ns id ew ill trigger th ea nti-thef ta lar m
system. Switc ho ff th ea lar m( Y
page 68).
Centrally locking an du nl ocking th e
vehicle from th ei nsideYou can centrall yl oc koru nloc kt he vehicle from
th ei ns ide. Thi sc an be useful if you wish to loc k
th ev ehicle befor ep ulling away, fo re xa mple.
X
To unlock : press butto n C .X
To lock : press butto n D .
If all th ed oors and th et ru nk lid are closed, th e
vehicle locks .76
Doors
Opening an dc losing

X
To open: pull remote operating switch C for
the trunk li du nti lt he trunk li do pe ns.
Emergenc yr eleas ef or the trunk
General notes
! The trunk li ds wi ng su pwar ds when opened.
Therefore, make sure tha tt her eiss uf ficient
clearance above the trunk lid.
The opening dimensions of the trunk li dc an be
found in the "Vehicle data" section
( Y
page 320).
If the trunk li dc an no longer be unlocked:R
using the SmartKey ,o rR
using the remote operating switch in the door
contro lp an el:
Use the emergency release on the insid eoft he
trunk lid.
Yo uc an reach the emergency release via the
trunk.
Opening X
Fol dt he rea rs ea tb ac kres tf orwards
( Y
page 240). X
Insert as ui tabl et ool D ,e .g .as crewdriver,
into opening C in the paneling.
The trunk li disr eleased. X
Ope nt he trunk lid.
Emergenc yr eleas eb uttonYo uc an open the trunk li df rom insid et he vehi-
cle with the emergency release button.
X
Press emergency release button C briefly.
The trunk li du nlocks and opens.
The trunk li dc an be unlocke da nd opene dw it h
the trunk li de mergency release when the vehi-
cle is stationary or whil ed riving.
The trunk li de mergency release does not open
the trunk li dift he battery is disconnected or
discharged.
Trunk li de mergency release light: R
Emergency release button C flashe sf or
30 minutes afte rt he trunk li diso pe ned.R
Emergency release button C flashe sf or
60 minutes afte rt he trunk li disc losed.
Side windows
Important safety notes
G WARNING
While opening the side windows ,b od yp ar ts
could become trappe db et ween the side win-
do wa nd the door frame as the side window
moves. There is ar is kofi njury.
Make sure tha tn obod yt ouche st he side win-
do wd ur ing the opening procedure. If some-Side windows 81
Opening and closing Z

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 ar isk of an accident.
Adjust the driver's seat, head restraint ,s teer-
ing wheel and mirror and fasten your seat belt
before startin gt he engine.
G WARNING
Children could injure themselves if they
adjust the steering wheel. There is ar isk 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 ar isk of an
accident.
Before startin go ff, make sure the steering
wheel is locked. Never unlock the steering
wheel while the vehicle is in motion. C
Release lever D
Adjust st he steering wheel height

take precedence ove rt he daytime running
lamps.
US Ao nly:
The daytime running lamps improve the visibility
of your vehicl ed ur in gt he day. To do this, the
daytime running lamps functio nm us tb e
switched on using the on-board computer
( Y
page 187).
If the engine is running and yo ut ur nt he light
switch to the ` or X position, the manual
setting st ake precedence ove rt he daytime run-
ning lamps.
Low-beam headlamps Even if the light senso rd oe sn ot detect tha titi s
dark, the parking lamps and low-bea mh ead-
lamps switch on when the ignition is switched on
and the light switch is se ttot he X position.
Thi sisa particularly usefu lf un ctio nint he event
of rain and fog. X
To switc ho nt he low-beam headlamps:
tur nt he SmartKe ytop osit ion H in the igni-
tio nl oc kors tart the engine.X
Turn the light switch to X .
The green X indicator lamp in the instru-
ment cluste rl ig hts up.
Rea rf og lampThe rea rf og lamp improves visibility of your
vehicl ef or the traffi cb ehin dint he event of thick
fog .P leas et ake note of the country-specific
regulations for the us eofr ea rf og lamps.X
To switc ho nt he rear fo gl amp: tur nt he
SmartKe yint he ignition lock to position H or
s tart
the engine.X
Turn the light switch to X or X .X
Press the ^ button.
The yellow ^ indicator lamp in the instru-
ment cluste rl ig hts up.X
To switc ho ff the rear fo gl amp: press the
^ button.
The yellow ^ indicator lamp in the instru-
ment cluste rg oe so ut .
i When the rea rf og lamp is switched on, the
cente rb rake lamp in the tai ll am ps wi tches off
du etoal egal requirement.
Parkin gl amps
! If the battery charge is ver yl ow ,t he parking
lamps or standing lamps ar ea ut omatically
switched off to enabl et he next engine start.
Alway sp ar ky ou rv ehicl es af el ya nd in aw el ll it area ,ina ccordance with the relevant legal
stipulations. Avoi du si ng the ` parking
lamps ove rap er io dofs ev eral hours. If pos-
sible, switch on the right-hand d or left-
hand c standing lamps. X
To switc ho n: tur nt he light switch to ` .
Th eg reen ` indicator lamp in the instru-
ment cluste rl ig hts up.
Standin gl ampsSwitching on the standing lamps ensures the
corresponding side of the vehicl eisi llumin ated.X
To switc ho nt he standin gl amps: the
SmartKe yisn ot in the ignition lock or it is in
position Z in the ignition lock. X
Turn the light switch to c (left-hand side of
the vehi cle) or d (
right-hand side of the
vehicle).
Combination switch
X
To indicate briefly: press the combination
switch briefl ytot he pressure point in the
directio nofa rr ow D or

Interior lighting control
General notes In order to preven tt he vehicle's battery from
discharging ,t he interio rl ighting function sa re
automatically deactivated after som et im e
except when th eS ma rtKey is in position H in
th ei gnition lock.
The color and brightness for th ea mbien tl ighting
may be set via th em ultimedia system; see th e
separat eo perating instructions.
Automati ci nterior lighting controlX
To switch on: set th es witch to center posi-
tion

If the battery voltage is too low, the rear window
defroster may switch off.
Activating/deactivating X
Turn the SmartKey to position H in the igni-
tion lock ( Y
page 122). X
Press the l button.
The indicator lamp in the l button lights
up or goes out.
Problems with the rear window defroster Problem
Possible causes/consequences and P Solutions
The rear window
defroster has deactiva-
ted prematurely or can-
not be activated. The battery has not been sufficiently charged. X
Switch off any consumers that are not required, e.g. reading lamps,
interior lighting or the seat heating.
When the battery is sufficiently charged, the rear window defroster
can be activated again.
Switching air-recirculatio nm ode
on/off
General notes You can deactivate the flow of fresh air if
unpleasant odors are entering the vehicle from
outside. The air already inside the vehicle will
then be recirculated.
If you switch on air-recirculation mode, the win-
dows can fog up more quickly, in particular at
low temperatures. Only use air-recirculation
mode briefl ytop revent the window sf rom fog-
ging up.
The operation of air-recirculation mode is the
same for all control panels.
Activating/deactivating X
Turn the SmartKey to position H in the igni-
tion lock ( Y
page 122).X
To activate: press the