2018 MERCEDES-BENZ CLA warning light

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

becomes .W hen the minimum distance is
reached, you hear ac ontinuous warning tone.
Deactivating or activating Parking
Assist PARKTRONIC
C
Indicator lampD
Deactivates or activates Parkin gA ssist
PARKTRONIC If indicator lamp C is lit, Parkin gA ssist
PARKTRONI Ci sd eactivated.
i Parkin gA ssist PARKTRONI Cisa utomati-
cally activated when you turn the SmartKey to
position 2 in the ignition lock.
Problems with Parking Assist PARKTRONIC Problem
Possible causes/consequences and P Solutions
Only the red segments in
the Parkin gA ssist
PARKTRONI Cw arning
displays are lit. You also
hear aw arning ton ef or
approximately two sec-
onds.
Parkin gA ssist
PARKTRONI Ci st hen
deactivated and the indi-
cator lamp on the
PARKTRONI Cb utton
lights up. Parkin gA ssist PARKTRONI Ch as malfunctioned and has been deacti-
vated. X
If problems persist ,h ave Parkin gA ssist PARKTRONI Cc hecked at a
qualified specialist workshop.
Only the red segments in
the Parkin gA ssist
PARKTRONI Cw arning
displays are lit. Parking
Assist PARKTRONI Ci s
then deactivated. The Parkin gA ssist PARKTRONI Cs ensor sa re dirty or ther eisi nter-
ference. X
Clean the Parkin gA ssist PARKTRONI Cs ensor s( Y
page 265).X
Switc ht he ignition back on.
The problem may be caused by an external source of radio or ultra-
sound waves. X
Check to see if Parkin gA ssist PARKTRONI Cw orks at ad ifferent
location. Driving systems 163
Driving and parking Z

Any unauthorized modification to thi sd ev ice
could voi dt he user’ sa ut hority to operate the
equipment.
Radar sensors The rada rs ensors for Blind Spo tA ssist ar ei nte-
grated into the rea rb um per. Make sure tha tt he
bumpers ar ef re ef rom dirt, ice or slush. The
sensors must not be covered ,f or exampl eb y
cycle racks or overhanging loads. Following a
severe impact or in the event of damage to the
bumpers, have the functio noft he rada rs ensors
checked at aq uali fied specialist workshop.
Blind Spo tA ssist ma ynol on ge rw or kp roperly.
Monitorin gr ang eoft he sensorsIn particular, the detection of obstacle sc an be
impaired if: R
ther eisd ir tont he sensors or anything else
covering the sensors R
ther eisp oo rv isibility ,e .g .d ue to fog ,h eavy
rain or snow R
an arrow vehicl et raveling in front, e.g .a
motorbike or bicycle R
the roa dh as ver yw id el an esR
the roa dh as narrow lanesR
yo ua re not driving in the middl eoft he laneR
ther ea re barriers or othe rr oa db ou ndaries
Vehicles in the monitoring range ar et hen not
indicated.
Blind Spo tA ssist monitors the area up to 10 ft
(3 m) behind your vehicl ea nd directl yn ext to it.
If the lanes ar en arrow ,v ehicles driving in the
lane beyond the lane next to your vehicl em a y be
indicated ,e specially if the vehicles ar en ot driv-
ing in the middl eoft hei rl an e. Thi sm ay be the
cas eift he vehicles ar ed riving on the inne rs id e
of thei rl an e.
Due to the nature of the system: R
warning sm ay be issued in error when driving
close to crash barriers or similar solid lane
borders. R
warning sm ay be interrupte dw he ny ou are
driving alongsid ep ar ticularly long vehicles,
such as trucks, for ap rolonge dt ime. Warning display
C
Warning display
Blind Spo tA ssist is not active at speed sb elow
approximatel y20m ph (30 km/h). Vehicles in
the monitoring range ar et hen not indicated.
Whe nB lind Spo tA ssist is activated ,i ndicator
lamp C in the exterio rm irrors lights up yellow
at speed sofupto20m ph (30 km/h). At speeds
above 20 mph (30 km/h), the indicator lamp
goe so ut and Blind Spo tA ssist is operational.
If av ehicl eisd et ecte dw it hi nt he blind spot
monitoring range at speed sa bo ve 20 mph
(30 km/h), warning lamp C on the correspond-
ing side lights up red .T hi sw ar ning is always
emitted when av ehicl ee nters the blind spot
monitoring range from behind or from the side.
Whe ny ou overtake av ehicle, the warning only
occurs if the difference in speed is less than
7m ph (12 km/h).
The yellow indicator lamp goe so ut if reverse
gear is engaged .Int hi se vent, Blind Spo tA ssist
is no longe ra ctive.
The brightness of the indicator/warning lamps
is adjusted automaticall ya ccording to the ambi-
ent light.
Collisio nw ar ning
If av ehicl eisd et ecte dint he monitoring range of
Blind Spo tA ssist and yo us wi tch on the corre-
sponding turn signal, ad ouble warning tone
sounds. Re dw ar ning lamp C flashes. If the turn
signa lr emains on, vehi cles detecte da re i ndica-
ted by the flashing of red warning lamp C .
There ar enof ur the rw ar ning tones.Driving systems 173
Driving an dp arking 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

Important safety notes
G WARNIN G
If you operate information systems and com-
munication equipmen ti ntegrate dint he vehi-
cle when driving ,y ou may be distracte df ro m
th et ra ffic situation .Y ou could also lose con-
trol of th ev ehicle. Ther eisar is kofana cci-
dent.
Only operate this equipmen tw hen th et ra ffic
situation permits. If you are no ts ur et ha tt hi s
is possible ,p ark th ev ehicl ep ayin ga ttention
to traffic condition sa nd operate th ee quip-
men tw hen th ev ehicl eiss ta tionary.
You must observ et he legal requirements for th e
country in whic hy ou are currentl yd riving when
operating th eo n-bo ard computer.
G WARNIN G
If th ei nstrumen tc luste rh as faile dorm al-
functioned, you may no tr ecognize function
restriction sins ystems relevan ttos afety. The
operating safet yofy our vehicl em ay be
impaired .T her eisar is kofana ccident.
Drive on carefully. Hav et he vehicl ec hecked
at aq ualified specialist workshop immedi-
ately.
The on-board computer only shows message so r
warning sf ro mc ertai ns ystems in th em ultifunc-
tion display. You should therefor em ak es ur e
your vehicl eiso perating safely at all times .
If th eo perating safet yofy our vehicl ei s
impaired ,p ull ove rass oo nasitiss af etodos o.
Contac taq ualified specialist workshop.
Fo rano verview, see th ei nstrumen tp anel illus-
tration ( Y
page 33).
Display sa nd operation
Instrumen tc luster lighting
The ligh ts ensor in th ei nstrumen tc luste ra uto -
matically control st he brightness of th em ulti-
function display. In daylight, th ed isplays in th e
instrumen tc luste ra re no ti lluminated. The lighting in th ei nstrumen tc luster, in th ed is-
plays and th ec ontrols in th ev ehicl ei nterior can
be adjusted usin gt he brightness control knob.
The brightness control knob is locate dont he
botto ml ef toft he instrumen tc luste r
( Y
page 33). X
Turn th eb rightness control knob clockwise or
counter-clockwise.
If th el igh ts witch is set to th e X , ` or
X position ,t he brightness is dependen t
upon th eb rightness of th ea mbien tl ight.
Speedometer with segments The speedometer is divided int os egments on
vehicles wit hD istance Pilot DISTRONIC.
The segments in th es peedometer indicat e
whic hs pee dr ange is available. R
Distanc eP ilot DISTRONI Cisa ctivated
( Y
page 151):
On eort wo segments in th es et spee dr ange
ligh tu p. R
Distanc eP ilot DISTRONI Cd etects av ehicl ei n
fron tm oving mor es lowly than th es to re d
speed:
The segments between th es pee doft he vehi-
cle in fron ta nd th es to re ds pee dl igh tu p.
Tachometer
! Do no td riv eint he overrevving range, as this
could damag et he engine.
The red ban dint he tachometer indicates th e
engine's overrevving range.
The engin eisl imite dw ithin ar ange to protect
th ee ng in ew hen th er ed ban disr eached.
Outsid et emperatur ed isplayYou should pay special attention to road condi-
tion sw hen temperatures are aroun df re ezing
point.
Bea rinm in dt ha tt he outside temperature dis-
play indicates th et em perature measured and
does no tr ecord th er oad temperature.
The outside temperature display is in th em ulti-
function display ( Y
page 179).176
Display sa nd operation
On-boar dc omputer and displays