2018 MERCEDES-BENZ CLA brake light

operates independently of the ECO start/stop
automatic engine switch-off function.
Key positions with the Start/Stop button
C
Start/Stop buttonD
Ignition lock
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light
up.
For further information on situations in which an
indicator lamp either fails to go out after the
engine is started or lights up while driving,
please refer to "Warning and indicator lamps in
the instrument cluster" ( Y
page 219).
If Start/Stop button C has not yet been
pressed, this is the same as the SmartKey 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 normal
using the SmartKey.
You can only switch between Start/Stop button
mode and SmartKey operation when the vehicle
is stationary. You must also engage park position ] .X
Remove Start/Stop button C from ignition
lock D .
You do not have to remove the Start/Stop but-
ton from the ignition lock when you leave the
vehicle. You should, however, alway st ake the
SmartKey with you when leaving the vehicle. 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 P R
Start the engine.
There is ar isk of an accident and injury.
When leaving the vehicle, alway st ake 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 ar isk of fatal injury. Therefore never leave
the engine runnin gine nclosed spaces with-
out sufficient ventilation. Driving 123
Driving and parking Z

the SmartKe yf ro mt he ignition, the automatic
transmission shifts to ] automatically.
With the Start/Sto pb utton: if yo ut he no pe n
the driver's door or the front-passenge rd oo r,
the automatic transmission shifts to ] auto-
matically.
If yo uw an tt he automatic transmission to
remai ninn eutral \\ ,e .g .w he nh av in gt he vehi-
cle cleane dinana ut omatic car wash with a
towing system: X
Vehicle sw it ht he Start-Sto pb utton:
remove the Start-Stop button fro mt he igni-
tio nl oc k.X
Insert the SmartKe yi nto the ignition lock.X
Al lv eh icles: switch the ignition on.X
Depres st he brake peda la nd kee pi t
depressed. X
Engage neutral \\ .X
Releas et he brake pedal.X
Releas et he electri cp ar king brake.X
Switch off the ignition and leav et he SmartKey
in the ignition lock.
Electric parking brake
General notes
G WARNING
If yo ul eave children unsupervised in the vehi-
cle ,t he yc ould se titinm otion by ,f or example:R
release the parking brake. R
shift the automatic transmission ou toft he
parking position P .R
start the engine.
In addition, the ym ay operate vehicl ee quip-
ment and become trapped .T here is ar is ko f
an accident and injury.
When leaving the vehicle, always take the
SmartKe yw it hy ou and lock the vehicle. Never
leav ec hildren unsupervised in the vehicle. The functio noft he electric parking brake is
dependent on the on-board voltage. If the on-
boar dv oltag eisl ow or there is am al functio ni n
the system, it ma yn ot be possibl etoa pply the
release dp ar king brake. X
If thi sist he case, onl yp ar kt he vehicl eo n
level ground and secur eittop revent it rolling
away. X
Shift the automatic transmission to position
] .
It ma yn ot be possibl etor elease an applied
parking brake if the on-board voltag eisl ow or
there is am al functio nint he system. Contact a
qualified specialis tw or kshop.
The electric parking brake performs af un ction
tes tatr egular intervals whil et he engine is
switched off .T he sound st ha tc an be he ar dw hile
thi siso ccurring ar en ormal.
Applyin gorr eleasing manually
X
To engage: push handle C .
When the electric parking brake is applied,
the red I (USA only) or $ (Canada
only) indicator lamp lights up in the instru-
ment cluster.
Th ee le ctric parking brake can also be applied
when the SmartKe yisr emoved.X
To release: pull handle C .
The red I (USA only) or $ (Canada
only) indicator lamp in the instrument cluster
goes out.
Th ee le ctric parking brake can onl yb e
released: R
if the SmartKe yisinp osit ion G or H in
the ignition lock ( Y
page 122 )o rR
if the ignition wa ss wi tched on using the
Start/Stop button142
Parking
Driving an dp arking

In addition to driving style, the actual consump-
tion is affected by other factors, such as: R
Load R
Tire pressure R
Cold start R
Choice of route R
Active electrical consumers
These factors are not include dint he ECO dis-
play.
An economical driving style specially requires
driving at moderate engine speeds.
Achieving ah igher valu eint he categories
"Acceleration" and "Constant": R
observe the gearshift recommendations. R
drive the vehicle in drive program C or E
(vehicles with aD YNAMIC SELECT button).
On long journeys at ac onstant speed ,e .g. on the
highway, only the outer area for "constant" will
change.
The ECO display summarizes the driving style
from the start of the journey to its completion.
Therefore, there are more marked changes in
the outer area satt he start of aj ourney. On lon-
ger journeys, there are fewer changes. For more
marked changes, perform am anua lr est
( Y
page 181).
For more information on the ECO display, see
( Y
page 180).
Braking
Important safety notes
G WARNING
If you shift down on as lippery road surface in
an attempt to increase the engine's braking
effect, the drive wheel sc ould lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on as lippery road surface.
Downhill gradients
! On long and steep gradients, you must
reduce the load on the brakes by shifting to a
lowe rg ear in good time. This allows you to
take advantage of engine braking. For this you
must first activate manua lg earshifting. This helps you to avoid overheating the brakes and
wearing them out excessively.
When you take advantage of engine braking, it
is possible that ad rive wheel wil ln ot rotate for
some time, e.g. on as lippery road surface.
This could cause damage to the drive train.
This type of damage is not covered by the
Mercedes-Benz warranty.
Briefly depressing the accelerator peda lo n
downhill gradients whil et he manua ld rive pro-
gram M is temporaril ya ctivated: the automatic
transmission may switch to the last active auto-
matic drive program E or S .T he automatic trans-
missio nm ay shift to ah ighe rg ear. This can
reduce the engine's braking effect.
Heavy and light loads
G WARNING
If you rest you rf oot on the brake peda lw hile
driving, the braking system can overheat. This
increases the stopping distance and can even
cause the braking system to fail .T here is a
risk of an accident.
Never use the brake peda lasaf ootrest. Never
depres st he brake peda la nd the accelerator
peda latt he same time.
! Depressing the brake peda lc onstantly
results in excessive and premature wea rt o
the brake pads.
If the brakes have been subjected to ah eavy
load ,don ot stop the vehicle immediately .D rive
on for as hort while. This allows the airflow to
cool the brakes more quickly.
Wet roads If you have driven for al ong time in heavy rain
withou tb raking, there may be ad elayed reac-
tion from the brakes when braking for the first
time. This may also occur after the vehicle has
been washed or driven through deep water.
You have to depres st he brake peda lm ore
firmly .M aintai nag reater distance from the
vehicle in front.
After driving on aw et road or having the vehicle
washed, brake firmly whil ep aying attention to
the traffic conditions. This wil lw arm up the
brake discs, thereby drying them more quickly
and protecting them against corrosion.146
Driving tips
Driving and parking

Limited braking performance on salt-
treated roads If you driv eons alted roads ,al ayer of salt resi-
due may for mont he brak ed isc sa nd brake
pads. This can result in as ignificantly longer
braking distance. R
In orde rtop revent any salt build-up, apply the
brakes occasionally while paying attention to
th et ra ffic conditions.R
Carefully depress th eb rak ep edal and the
beginnin ga nd end of aj ou rney.R
Maintain ag reater distanc etot he vehicle
ahead.
Servicing th eb rakes
! The brak ef luid level may be to ol ow, if:R
if th er ed brak ew arning lamp light supi n
th ei nstrumen tc luster andR
you hear aw arning tone while th ee ngine is
running
Observe additional warning messages in the
multifunction display.
The brak ef luid level may be to ol ow due to
brak ep ad wear or leaking brak el ines.
Hav et he brak es ystem checked immediately.
Consult aq ualifie ds pecialist workshop to
arrange this.
! Af unction or performanc et es ts hould only
be carried out on a2 -a xle dynamometer. If
you wish to operate th ev ehicle on such a
dynamometer, please consult aq ualifie ds pe-
cialis tw orkshop in advance. You could oth-
erwis ed amage th ed riv et ra in or th eb rake
system.
! As th eE SP ®
system operates automatically,
th ee ngine and th ei gnitio nm ust be switched
off (th eS ma rtKey must be in position

If you leave the engine or the auxiliary heating
running, make sure the exhaust pipe and area
around the vehicle are clear of snow. To
ensure an adequate supply of fresh air, open a
window on the side of the vehicle that is not
facing into the wind.
Have you rv ehicle winter-proofed at aq ualified
specialist workshop at the onset of winter.
Drive particularly carefully on slippery road sur-
faces. Avoid sudden acceleration, steering and
braking maneuvers. Do not use cruise control or
Distance Pilo tD ISTRONIC.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed: X
Shift the transmission to position N .X
Try to bring the vehicle under control using
corrective steering.
The outsid et emperature indicator is not
designed to serve as an ice-warning device and
is therefore unsuitable for that purpose.
Changes in the outsid et emperature are dis-
played after as hort delay.
Indicated temperature sj ust above the freezing
point do not guarantee that the road surface is
free of ice. The road may still be icy, especially in
woode da rea soronb ridges.
You shoul dp ay specia la ttention to road condi-
tions when temperature sa re around freezing
point.
For more information on driving with snow
chains, see ( Y
page 290).
For more information on driving with summer
tires, see ( Y
page 289).
Observe the notes in the "Winter operation" sec-
tion ( Y
page 289).
Drivin gs ystems
Cruise control
General notes
Cruise control maintains ac onstant road speed
for you .Itb rakes automatically in order to avoid
exceeding the set speed .Onl ong and steep
downhill gradients, especially if the vehicle is
laden, you must select al ow gear in good time.
You need to shift manually using the steering
wheel paddle shifters beforehand. By doing so,
you wil lm ake use of the braking effect of the engine. This relieves the load on the brake sys-
tem and prevents the brakes from overheating
and wearing too quickly.
When the engine is running, you can use the
cruise control lever to limi tt he speed to any
speed betwee n20m ph (30 km/h )a nd the tech-
nicall yp ermitted maximum speed of the vehicle.
Use cruise control only if road and traffic con-
ditions make it appropriate to maintain as teady
speed for ap rolonge dp eriod.
The speed indicated in the speedometer may
differ slightly from the speed stored.
Important safety notes If you fail to adapt you rd riving style, cruise con-
trol can neither reduce the risk of an accident
nor override the law sofp hysics. Cruise control
cannot take into account the road, traffic and
weather conditions. Cruise control is only an
aid .Y ou are responsible for the distance to the
vehicle in front, for vehicle speed ,f or braking in
good time and for staying in you rl ane.
Do not use cruise control: R
in road and traffic conditions which do not
allow you to maintain ac onstant speed ,e .g. in
heavy traffic or on winding roads R
on slippery road surfaces .B raking or accel-
erating could cause the drive wheel stol ose
traction and the vehicle could then skid R
in poor visibility, e.g. due to fog, heavy rain or
snow
If there is ac hange of drivers, advise the new
driver of the speed stored.
Cruise control lever
C
Activates or increases speed
D
Activates or reduces speedDriving systems 149
Driving and parking Z

i When you switch off the engine, the last
speed stored is cleared.
Distance Pilot DISTRONIC
General notes Distance Pilot DISTRONIC regulates the speed
and automatically helps you maintain the dis-
tanc etot he vehicle detected in front. Vehicles
are detected with the aid of the radar sensor
system. Distance Pilot DISTRONIC brakes auto-
matically to avoid exceedin gt he set speed or to
maintain the designated distanc ef rom the vehi-
cle in front.
If Distance Pilot DISTRONIC detect st hat there is
ar isk of ac ollision, you will be warned visually
and acoustically. Without your intervention, Dis-
tanc eP ilot DISTRONIC cannot prevent ac olli-
sion. An intermittent warning ton ew ill then
sound and the distanc ew arning lamp will light
up in the instrument cluster. Brake immediately
in order to increase the distanc etot he vehicle in
fron tort ake evasive action provided it is safe to
do so.
Distance Pilot DISTRONIC operates in the range
between 0m ph (0 km/h) and 120 mph
(200 km/h).
Change into al ower gear in good time on long
and steep downhill gradients .T his is especially
importan tift he vehicle is laden. By doing so, you
will make use of the braking effect of the engine.
This relieves the load on the brake system and
prevent st he brakes from overheatin ga nd wear-
ing too quickly.
Do not use Distance Pilot DISTRONIC on roads
with steep gradients.
For Distance Pilot DISTRONIC to assist you
when driving, the radar sensor system must be
operational.
Sinc eD istance Pilot DISTRONIC transmits radar
waves, it can resemble the radar detectors of
the responsible authorities. You can refer to the
relevant chapter in the Operator' sM anual if
questions are asked about this.
i USA only: This device has been approved by
the FCC as a" Vehicular Radar System". The
radar sensor is intended for use in an auto-
motive radar system only. Removal, tamper-
ing, or altering of the device will void any war-
ranties, and is not permitted by the FCC. Do not tamper with, alter, or use in any non-
approved way.
An yu nauthorized modification to this device
could void the user's authority to operate the
equipment.
i Canada only: This device complies with
RSS-210 of Industry Canada. Operation is
subject to the following two conditions:
1. This device may not cause interference,
and
2. This device must accept any interference
received, including interference that may
cause undesired operation of the device.
Removal, tampering, or altering of the device
will void any warranties, and is not permitted.
Do not tamper with, alter, or use in any non-
approved way.
An yu nauthorized modification to this device
could void the user's authority to operate the
equipment.
Important safety notes
G WARNING
Distance Pilot DISTRONIC does not react to: R
people or animals R
stationary object sont he road, e.g. stopped
or parked vehicles R
oncoming vehicles and crossin gt raffic
As ar esult, Distance Pilot DISTRONIC may
neither give warnings nor intervene in such
situations. There is ar isk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
G WARNING
Distance Pilot DISTRONIC cannot always
clearly identif yo ther road users and complex
traffic situations.
In such cases, Distance Pilot DISTRONIC may: R
give an unnecessary warning and then
brake the vehicle R
neither give aw arning nor intervene R
accelerat eorb rake unexpectedly
There is ar isk of an accident.Driving systems 151
Driving and parking Z

Switching on Blind Spot Assist X
Make sure that Blind Spot Assist is activated
in the on-board computer ( Y
page 186).X
Turn the SmartKey to position H in the igni-
tion lock.
Warning lamps C in the exterior mirrors light
up red for approximately 1.5 seconds and
then turn yellow.
Lane Keeping Assist General notes
Lane Keeping Assist monitor st he area in front of
your vehicle by means of multifunction cam-
era C which is attached behind the top of the
windshield. Lane Keeping Assist detect sl ane
markings on the road and can warn you before
you leave your lane unintentionally.
This function is available in the range between
40 mph and 120 mph (60 km/h and 200 km/h).
Aw arning may be given if af ront wheel passes
over al ane marking. It will warn you by means of
intermittent vibration in the steering wheel for
up to 1.5 seconds.
Important safety notes
G WARNING
Lane Keeping Assist cannot always clearly
detect lane markings.
In such cases, Lane Keeping Assist can: R
give an unnecessary warning R
not give aw arning
There is ar isk of an accident.
Always pay particular attention to the traffic
situation and keep within the lane, especially
if Lane Keeping Assist alerts you. G WARNING
The Lane Keeping Assist warning does not
return the vehicle to the original lane. There is
ar isk of an accident.
You should always steer, brake or accelerate
yourself, in particular if warned by Lane Keep-
ing Assist.
If you fail to adapt your driving style, Lane Keep-
ing Assist can neither reduce the risk of an acci-
dent nor override the laws of physics. Lane
Keeping Assist cannot take into account the
road, traffic and weather conditions. Lane Keep-
ing Assist is merely an aid. You are responsible
for the distance to the vehicle in front ,f or vehi-
cle speed, for braking in good time and for stay-
ing in your lane.
The Lane Keeping Assist does not keep the vehi-
cle in the lane.
The system may be impaired or may not function
if: R
there is poor visibility, e.g. due to insufficient
illumination of the road, or due to snow, rain,
fog or spray R
there is glare, e.g. from oncomin gt raffic, the
sun or reflection from other vehicles (e.g. if
the road surface is wet) R
the windshield is dirty, fogged up, damaged or
covered, for instanc ebyas ticker, in the vicin-
ity of the camera R
there are no or several unclear lane markings
for one lane, e.g. roadworks R
the lane markings are worn away ,d ark or cov-
ered up, e.g. by dirt or snow R
the distance to the vehicle in front is too short
and thus the lane markings cannot be detec-
ted R
the lane markings change quickly, e.g. lanes
branch off, cross one another or merge R
the road is narrow and winding R
there are highly variable shade condition so n
the roadway
Switching on Lane Keeping Assist X
Switch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard or Adaptive ( Y
page 174).
If you drive at speeds above 40 mph
(60 km/h) and lane markings are detected,
the lines in the assistance graphic are shown174
Driving systems
Driving and parking

Display messages
Possible causes/consequences and P Solutions
The yellow $ warning lamp lights up. The red I (US Ao nl y)
or $ (Canada only) indicator lamp flashes for about te ns econds
after th ee lectric parking brak eh as been applie dorr eleased. It then
goe so ut or remain sl it .
The electric parking brak eism alfunctioning .X
Switc ho ff th ei gnition and tur nitb ac ko n.X
Apply th ee lectric parking brake.
If it is no tp ossibl etoe ng age th ee lectric parking brake:X
Shift th et ra nsmission to position E .X
Visit aq ualified specialist workshop .
If it is no tp ossibl etor elease th ee lectric parking brak em anually:X
Releas et he electric parking brak ea utomatically ( Y
page 142).
If th ee lectric parking brak es ti ll canno tber eleased:X
Consult aq ualified specialist workshop .
The yellow $ warning lamp lights up. If you manually apply or
release th ee lectric parking brake, th er ed I (US Ao nl y) or $
(Canada only) indicator lamp flashes .
The electric parking brak eism alfunctioning .Itisn ot possibl etoa pply
th ee lectric parking brak em anually.X
Shift th et ra nsmission to position E ,ast he electric parking
brak eisn ot applie da utomatically.X
Visit aq ualified specialist workshop .
I (US A
only)
$ (Canada
only)
Parkin gB rake Inop‐
erativ e The yellow $ warning lamp lights up. The red I (US Ao nl y)
or $ (Canada only) indicator lamp flashes for about te ns econds
after th ee lectric parking brak eh as been applie dorr eleased. It then
goe so ut or remain sl it .
The electric parking brak eism alfunctioning ,e .g .b ecause of over-
voltag eoru ndervoltage. X
Remove th ec aus ef or th eo vervoltage or undervoltage, e.g. by
charging th eb attery or restarting th ee ng ine.X
Engage or release th ee lectric parking brake.
If it remain si mpossible to apply or release th ee lectric parking brake:X
Switc ho ff th ei gnition and tur nitb ac ko n.X
Engage or release th ee lectric parking brake.
If th ee lectric parking brak es ti ll canno tber eleased:X
Consult aq ualified specialist workshop .
If th ee lectric parking brak es ti ll canno tbea pplied:X
Visit aq ualified specialist workshop .196
Display messages
On-boar dc omputer an dd isplays