2020 MERCEDES-BENZ CLS COUPE engine overheat

&
DANG ER Risk of fata l injury due topoi‐
sonous exhaust gases
If th eta ilpipe is bloc ked or suf ficient ventila‐
tion is not possible, poisonous exhaust gases
such as carbon monoxide may enter theve hi‐
cle. This is the case when theve hicle
becomes stuck in sn ow,fo rex ample. #
Keep theta ilpipe and the area around
th eve hicle free from snow when the
engine or thest ationary heater are run‐
ning. #
Open a window on the side of theve hi‐
cle facing away from the wind toensure
an adequate supply of fresh air. &
WARNING Risk of accident due tothe
brake sy stem overheating
If yo u lea veyour foot on the brake pedal
when driving, the brake sy stem may over‐
heat.
This increases the braking dis tance and the
brake sy stem may evenfa il. #
Never use the brake pedal as a foot re st. #
Do not depress the brake pedal and the
accelerator pedal at the same time
while driving. *
NO
TEEngine dama gedue toexcessively
high engine speeds The engine will be damaged if
you drive with
th e engine in theov errevving range. #
Do not drive wi th the engine in theove r‐
re vving range. *
NO
TECausing wearto the brake linings
by permanently depressing the brake
pedal #
Do not permanently depress the brake
pedal while driving. #
Touse braking ef fect of the engine,
shift toa lo werge ar in good time. *
NO
TEDama getothe driv etra in and
engine when pulling away #
Do not warm upthe engine while the
ve hicle is stationar y.Pull away immedi‐
atel y. #
Avoid high engine speeds and driving at
full thro ttle until the engine has reached
its operating temp erature. *
NO
TEDama getothe catalytic con verter
due tonon-combu sted fuel The engine is not
running smo othly and is
misfiring.
Non-combus ted fuel may get into the cata‐
lytic con verter. #
Only depress the accelera tor pedal
slightl y. #
Have the cause rectified immediately at
a qu alified specialist workshop. Note
s on driving on salt-treated roads
The braking ef fect is limited on salt-trea ted
ro ads. 15 4
Driving and pa rking

#
Toavo id creating ano ther electros tatic
ch arge , do not getinto theve hicle again
during there fuelling process. &
WARNING Risk offire from fuel mixture
Ve hicles with a diesel engine:
While the engine is running, component
pa rts in theex haust sy stem may overheat
without warning. #
Neverre fuel using petrol. #
Never mix petrol with diesel fuel. *
NO
TEDama gecaused bythe wrong fuel Ve
hicles with a petrol engine:
Even small amounts of the wrong fuel could
re sult in damage tothe fuel sy stem, the
engine and the emission control sy stem. #
Only refuel using unleaded, sulphu r-free
petrol that con form sto European
EN 228, or an equi valent specification. Fu
el of this specification may con tain up to
10 %ethanol. Your vehicle is suitable for use
with E10 fuel.
Ne verre fuel with one of thefo llowing fuels:
R diesel
R regular petrol with an octane number
lo we rth an 91 RON
R petrol with more than 10%ethanol byvol‐
ume, e.g. E15, E20, E85, E100
R petrol with more than 3% me thanol by
vo lume, e.g. M15, M30
R petrol with additives con taining me tal
If yo u ha veacciden tally refuelled with the
wrong fuel: #
do not swit ch the ignition on. #
Consult a qualified specialist workshop. *
NO
TEDama gecaused bythe wrong fuel Ve
hicles with a diesel engine: Even small amounts of
the wrong fuel could
re sult in damage tothe fuel sy stem, the
engine and the emission control sy stem. #
Only refuel using sulphu r-free diesel
fuel that con form sto European stand‐
ard EN 590, or an equivalent specifica‐
tion.
In countries without sulphur-f ree diesel
fuel, refuel using only lo w-sulphur diesel
fuel with a sulphur content less than
50 ppm.
Ne verre fuel using any of thefo llowing fuels:
R petrol
R marine diesel
R heating oil
R pure bio-diesel fuel or vege table oil
R paraf fin or kerosene
If yo u accidentally refuel with the wrong fuel: #
Do not switch the ignition on. #
Consult a qualified specialist workshop. Driving and parking
167

The
ATTENTION ASSIST dr owsiness or alertness
assessment is reset and restar ted when continu‐
ing the journey in thefo llowing situations:
R Ifyo u swit choff the engine.
R Ifyo u unfas tenyo ur seat belt and open the
driver's door (e.g. tochange drivers or take a
break).
Setting ATTENTION ASSI ST
Multimedia sy stem:
4 © 5
Settings 5
Assistance
5 Attention Assist
Setting options #
Select Standard, SensitiveorOff.
Suggesting a rest area #
Select Suggest rest area . #
Activate or deacti vate the function.
If AT TENTION ASSIST de tects fatigue or
increasing la ckof attention, it suggests a
re st area in the vicinit y. #
Select the sugges tedre st area.
Yo u are guided tothe selected rest area. Cruise cont
rol and limiter Fu
nction of cruise control
Cruise cont rolre gulates the speed totheva lue
selec tedby the driver.
If yo u accelerate toove rtake, forex ample, the
st ored speed is not dele ted. If youre mo veyour
fo ot from the accelerator pedal af terove rtaking,
cruise control will resume speed regulation back
to thestored speed.
Yo u can store any speed abo ve20 km/h up to
th e maximum design speed or up tothe set win‐
te r tyre limit.
Obser vethe no tes on driving sy stems and your
re sponsibility; you may otherwise failto recog‐
nise dangers (/ page 178).
Me rcedes‑AMG vehicles: cruise control is avail‐
able up toa maximum speed of 250 km/h.
Displ ays on the multifunction display
R h (gre y): cruise cont rol is selec ted but
not yet acti vated.
R h (green): cruise control is active. A
stored speed appears along with theh dis‐
pla y.
% The segments extending from the cur rent
st ored speed tothe end of the scale, or to
th e set winter tyre limit, light up in the
speedome ter.
Sy stem limits
Cruise control may be unable tomaintain the
st ored speed on uphill gradients. The stored
speed is resumed when the gradient evens out.
Change into a lo werge ar in good time on long
and steep downhill gradients. Take particular
no te ofthis when driving a laden vehicle. By
doing so, you will make use of the engine's brak‐
ing ef fect. This relie vesth e load on the brake
sy stem and pr events the brakes from overheat‐
ing and wearing tooqu ickl y.
Do not use cruise control in thefo llowing situa‐
tions:
R In traf fic situations whi chrequ ire frequent
ch anges of speed, e.g. in heavy traf fic, on
winding roads. Driving and parking
187

#
With your hand flat, push down active bonnet
1 inthe area around the hinges on bo th
sides (ar rows).
In doing so, the actuator is depressurised
and you may hear a hissing sound.
The engine bonnet must en gage in position. #
Ifth e active bonn etcan be raised slight lyat
th ere ar in the area of the hinges, repeat the
st ep until it engages cor rectl y. Opening and closing
the bonnet &
WARNING Risk of accident due todriv‐
ing with the bonn etunlo cked
The bonn etmay open and block your vie w. #
Neverre lease the bonn etwhen driving. #
Before every trip, ensure that the
engine bonn etis loc ked. &
WARNING Risk of accident and inju ry
when opening and closing the bonn et
The bonnet may suddenly drop into the end
position.
There is a risk of injury for an yone in the bon‐
net's range of mo vement. #
Open or close the bonn etonly when
th ere is nobody in the bonn et's range of
mo vement. &
WARNING Danger of bu rns when open‐
ing the bonn et
If yo u open the engine bonn etwhen the
engine has overheated or during a fire inthe
engine compartment, you could come into
contact with hot gases or other escaping
operating fluids. #
Before opening the bonn et, allow the
engine tocool down. #
Intheeve nt of a fire inthe engine com‐
partment, keep the engine bonn et
closed and call thefire service. &
WARNING Risk of inju rydue tomoving
parts
Components in the engine compartment may
continue running or start up sudden ly,even if
th e ignition is switched off.
Make sure of thefo llowing before per form ing
ta sks in the engine compartmen t: #
Switch the ignition off. #
Neverre ach into the danger zone sur‐
ro unding moving co mponents, e.g. the
ro tation area of thefa n. #
Remo vejewe llery and watches. #
Keep items of clo thing and hair away
from moving parts. &
WARNING Risk of inju ryfrom touching
co mp onents under voltage
The ignition sy stem and the fuel injection
sy stem workunder high voltage. You could
re cei vean electric shoc k.294
Maintenance and care

Ha
ve the brake fluid regularly replaced at a
qu alified specialist workshop.
Only use a brake fluid appr ovedby Mercedes-
Benz according toMB-F reigabe or MB-Appr oval
33 1.0. Coolant
Note
s on coolant
Obser vethe no tes on operating fluids
(/ page 347). &
WARNING Risk offire ‑ and inju ryfrom
antifreeze
If antifreeze comes into contact with hot
component parts in the engine compart‐
ment, it may ignite. #
Allow the engine tocool down before
yo uto p up the antif reeze. #
Make sure that no antifreeze spills out
next tothefiller opening. #
Thoroughly clean the antif reeze from
component parts before starting the
ve hicle. *
NO
TEDama gecaused byincor rect cool‐
ant #
Only use coolant that has been pre‐
mixed with therequ ired antifreeze pro‐
te ction.
Information on coolant is available at thefo l‐
lowing locations:
R inthe Mercedes-Benz Specification for
Operating Fluids 310.1
- at https://be vo.mercedes-benz.com
- inthe Mercedes-Benz BeVo app
R at a qualified specialist workshop *
NO
TEOverheating at high outside tem‐
peratures If an inapp
ropriate coolant is used, the
engine cooling sy stem is not suf ficiently pro‐
te cted against overheating and cor rosion at
high outside temp eratures. #
Alw ays use coolant appr ovedby
Mercedes-Benz. #
Obser vethe instructions in the
Mercedes-Benz Specifications for Oper‐
ating Fluids 310.1. Ha
ve the coolant regularly replaced at a qualified
specialist workshop.
Proportion of antifreeze concentrate in the
engine cooling sy stem:
R a minimum of 50% (antifreeze pr otection
down toappr oximately -37°C)
R a maximum of 55% (antifreeze pr otection
down to-45°C) Note
s on windscreen washer fluid Obser
vethe no tes on operating fluids
(/ page 347). &
WARNING ‑ Risk of fire and injury due to
windscreen washer concentrate
Wi ndsc reen washer concentrate is highly
fl ammable. It could ignite if it comes into
con tact wi thhot engine component parts or
th eex haust sy stem. Te
ch nical da ta355

Engine
Display messages
Possible causes/consequences and M
MSolutions
To switch off the engine,
press the Start/Stop but-
ton for at least 3 seconds
or 3 times. *Y
ou ha vepressed thest art/ stop button while theve hicle is in motion. #
Information about switching off the engine while driving (/ page149).
+
Top up coolant See Own-
er’s Manual *T
he coolant le vel is too lo w.
* NO
TEEngine dama gedue toinsuf ficient coolant #
Avoid long journe yswith insuf ficient coolant. #
Add coolant (/ page 297). #
Have the engine cooling sy stem checked at a qualified specialist workshop.
ÿ
Coolant Stop vehicle
Switch engine off *T
he coolant is too hot. #
Stop theve hicle immediately in accordance with the traf fic conditions and switch off the engine. &
WARNING Danger of bu rns when opening the bonn et
If yo u open the engine bonn etwhen the engine has overheated or during a fire inthe engine compartment, you
could come into contact wi thhot gases or other escaping operating fluids. #
Before opening the bonn et, allow the engine tocool down. Display messages and
warning/indicator lamps 375

Display messages
Possible causes/consequences and M
MSolutions #
Consult a qualified specialist workshop.
Reversing not poss. Con-
sult workshop *
The transmission is malfunctioning. The transmission position kcannot be selected. #
Consult a qualified specialist workshop.
Transmission Malfunction
Stop *
The transmission is malfunctioning. The transmission shifts toneutral iautomatically. #
Stop theve hicle immediately in accordance with the traf fic conditions. #
Depress the brake pedal. #
Enga gepark position j. #
Consult a qualified specialist workshop.
Stop vehicle Leave engine
running Wait Transmission
cooling *T
he transmission is overheating. Pulling away may be temp orarily impaired or not possible. #
Stop theve hicle immediately in accordance with the traf fic conditions. Do not continue driving. #
Lea vethe engine running. #
Wait until the display message disappears before pulling away.
Auxiliary battery malfunc-
tion *T
he auxiliary batteryforth e transmission is no longer being charge d. #
Consult a qualified specialist workshop. #
Untilthen, alw ays select park position jmanually before you swit choff the engine. #
Before leaving theve hicle, apply the electric parking brake. Display messages and
warning/indicator lamps 37 9

Engine
Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
ÿ Coolant warning lamp (red) *T
he red coolant warning lamp is lit while the engine is running.
Po ssible causes:
R The temp erature sensor is malfunctioning
R The coolant le vel is too low
R The air supply tothera diator is obstructed
R The radiator fan is faulty
R The engine coolant pump is faulty
If th ere is an additional warning tone, the coolant temp erature has exceeded 120°C. &
WA RNING Danger of bu rns when opening the bonn et
If yo u open the engine bonn etwhen the engine has overheated or during a fire inthe engine compartment, you
could come into contact wi thhot gases or other escaping operating fluids. #
Before opening the bonn et, allow the engine tocool down. #
Intheeve nt of a fire inthe engine compartment, keep the engine bonn etclosed and call thefire service. #
Stop theve hicle immediately in accordance with the traf fic conditions and switch off the engine. Do not continue
driving. #
Notethe messages on the multifunction displa y.41 8
Displaymessa ges and warning/indicator lamps