
#
Check the coolant temp erature display in the
instrument clus ter.
The coolant temp erature must be below
70 °C. #
Slowly turn cap 1anti-clockwise torelie ve
ov erpressure. #
Continue turning cap 1anti-clockwise and
re mo veit.
The coolant le vel is cor rect:
R ifth e engine is cold, up tomar ker bar 2
R ifth e engine is warm, up to1.5 cm over
mar ker bar 2 #
If necessar y,top up with coolant that has
been appr ovedby Mercedes-Benz.
R Further information on coolant
(→ page 459). To
pping up the windsc reen washer sy stem &
WARNING Danger of bu rns from hot
component parts in the engine compart‐
ment
Cer tain component parts in the engine com‐
partment may be very hot, e.g. the engine,
th era diator and parts of theex haust sy stem. #
Let the engine cool down and only
to uch the component parts described
below: &
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 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. #
Make sure that no windsc reen washer
concentrate spills out next tothefiller
opening. 394
Maintenance and care

*
NO
TEDamaging the battery thro ugh
ove rvoltage When using a battery
charge r without a maxi‐
mum charging voltage, the battery or the
ve hicle electronics may be damaged. #
Only use battery charge rs with a maxi‐
mum charging voltage of 14.8 V. &
WARNING Risk ofexplosion from hydro‐
ge nga s igniting
A battery generates hydrogen gas during the
ch arging process. If there is a short circuit or
spar ksstart toform ,th ere is a danger of the
hy drogen gas igniting. #
Make sure that the positive term inal of
th e connected battery does not come
into conta ct withvehicle parts. #
Never place me tal objects or tools on a
batter y. #
When connecting and disconnecting the
batter y,yo u must obse rveth e descri‐
bed order forth e battery clamps. #
When giving starting assis tance, al ways
make sure that you on lyconnect bat‐
te ry term inals with identical polarity. #
During starting assis tance, you must
obse rveth e described order for con‐
necting and disconnecting the jump
lead. #
Do not connect or disconnect the bat‐
te ry cla mp s while the engine is running. &
WARNING Risk ofexplosion during
ch arging process and starting assis tance
During thech arging process and starting
assis tance, the battery may release an explo‐
sive gas mixture. #
Avoid fire , naked flames, creating
spar ksand smoking. #
Make sure that there is suf ficient venti‐
lation du ring thech arging process and
during starting assis tance. #
Do not lean over a batter y. &
WARNING Risk ofexplosion from a fro‐
zen battery
A dischar ged battery may freeze at temp era‐
tures slightly abo veor below freezing point.
During starting assis tance or battery charg‐
ing, bat tery gas may be released. #
Alw aysth aw a frozen bat tery out first
before charging it or per form ing start‐
ing assis tance. If
th e indicator/warning lamps in the instrument
clus ter do not light up at low temp eratures, it is
ve ry likely that the dischar ged battery has fro‐
zen. In this case you may neither jump-s tart the
ve hicle nor charge the batter y.
The service life of a battery that has been
th awe d may be dramatically shor tened. The
st arting characteristics may be impaired, espe‐
cially at low temp eratures.
It is recommended that you ha veathaw ed bat‐
te ry checked at a qualified specialist workshop. 416
Breakdown assis tance

Model
of whichreser ve
fuel
CLS 450 4MATIC 7.0 litres
or
12 .0 litres
All other models 7.0 litres Ad
blue ® Note
s onAdBlue ®
Obser vethe no tes on operating fluids
(→ page 452).
Ad Blue ®
is a wate r-soluble fluid forth eNOx
ex haust gas af tertre atment of diesel engines.
* NO
TEMalfunctions due tothe dilution of
Ad Blue ®
or the use of additive-enhanced
Ad Blue ® The function of
the NOx exhaust gas af ter‐
treatment can be impaire dby the use of
unsuitable denoxification agents. #
Only use AdBlue ®
in accordance wi th
ISO 222 41 . #
Do not dilu teAd Blue ®
wi th wate r. #
Do not use additive-enhanced AdBlue ®
. *
NO
TEDama geand malfunctions due to
impurities in AdBlue ® Consequences of impu
rities in AdBlue ®
:
R increased emission values
R damage tothe catalytic con verter
R NOx exhaust gas af tertre atment malfunc‐
tions #
Avoid impurities in AdBlue ®
. Ad
Blue ®
re sidues cr ystallise af ter a period of
time, and contamina tethe sur faces wi thwhich
th ey come into contact. Clean the dirty sur faces
wi th wate r as soon as possible.
When you open theAd Blue ®
tan k,small
amounts of ammonia vapour may escape. Do
not inhale any ammonia vapours that may be re
leased. Only fill th eAd Blue ®
tank in well-venti‐
lated areas.
Ad Blue ®
filling capacity and consum ption
To tal capacity of AdBlue ®
tank Mode
lT otal capacity
All models 23.5 litres Ad
Blue ®
consu mption
Like fuel consu mption, AdBlue ®
consu mption is
highly dependent upon driving style and operat‐
ing conditions. Forth is reason, your vehicle's
actual consum ption figures under normal operat‐
ing conditions may dif fer from the consum ption
fi gures calculated. AdBlue ®
consu mption is
between 1% and 5% of fuel consumption. Ha ve
th eAd Blue ®
supply checked at a qualified spe‐
cialist workshop before making journe ysoutside
of Europe. Before a longer stay outside of
Europe, consult a qualified specialist workshop.
Display theAd Blue ®
ra nge and le vel
( → page 258). Te
ch nical da ta457

Display messages
Possible causes/consequences and M
MSolutions
4 Engine oil level Stop vehi-
cle Switch engine off *D
isplay message only for cer tain engines:
The engine oil le vel is too lo w.
* NO
TEEngine dama gecaused bydriving with insuf ficient engine oil #
Avoid long journe yswith insuf ficient engine oil. #
Pull over and stop theve hicle safely as soon as possible, paying attention toroad and traf fic conditions. Do not
continue driving under any circums tances. #
Switch off the engine. #
Add 1 l of engine oil. #
Check the engine oil le vel.
To p up the engine oil (→ page 392).
No tes on engine oil (→ page 458).
4 Engine oil level Reduce oil
level *D
isplay message only for cer tain engines:
The engine oil le vel is too high.
* NO
TEEngine dama gecaused bydriving with excess engine oil #
Avoid long journe yswith excess engine oil. #
Consult a qualified specialist workshop immediately and ha vethe engine oil siphoned off. 498
Display messages and warning/indicator lamps

Display messages
Possible causes/consequences and M
MSolutions
ï Check trailer hitch lock
(white display message) *T
he trailer tow hit chis not operational when you are driving with a trailer. #
Stop theve hicle immediately, paying attention toroad and traf fic conditions, and switch off the engine. #
Uncouple the trailer and secure it against rolling away. #
Initiate a new swivelling procedure (→ page246). #
Ifth e ball coupling is extended, press and hold the button on the boot lid until the ball coupling engages
beneath the bumper. #
When the display message disappears, couple up the trailer and drive on. &
WARNING Risk of an accident if the ball neck is not loc ked
If th e ball neck is not in the loc ked position, the trailer may come loose. #
Pull over and stop theve hicle safely as soon as possible, paying attention toroad and traf fic conditions.
Do not continue driving under any circums tances. #
Uncouple the trailer and secure it against rolling away. #
Initiate a new swivelling procedure and do not re-couple the trailer until the display message disappears. If
th e display message does not disappear, the trailer tow hit chis defective and the ball coupling is not loc ked. #
Do not couple up the trailer. Drive on without the trailer. No tethere duced ground clearance due tothe
unlo cked ball coupling. #
Consult a qualified specialist workshop.
The trailer tow hit chis not operational when theve hicle is at a standstill. 512
Displaymessa ges and warning/indicator lamps

8
Fu
elreser vewith fuel filler flap loca‐
tion indicator (→ page 536)
? Coolant
too hot/cold (→ page 536)h
Ty
re pressure monitoring sy stem
(→ page 539) ï
Tr
ailer hit chis not operational or is
swivelling (→ page 534) Saf
ety sy stems Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
J Brake sy stem warning lamp
(yellow) The
yellow brake sy stem warning lamp is lit while the engine is running. &
WARNING Risk of an accident due toa brake sy stem malfunction
If th e brake sy stem is malfunctioning, braking characteristics may be impaired. #
Drive on carefull y. #
Have the brake sy stem checked immediately at a qualified specialist workshop. #
Adjust your speed and continue todrive carefull y,leaving a suitable dis tance totheve hicle in front. #
Ifth e multifunction display sho wsa display message, please obse rveth is. #
Consult a qualified specialist workshop. Display messages and
warning/indicator lamps 525

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions #
Consult a qualified specialist workshop.
! ABS warning lamp The
yellow ABS warning lamp is lit while the engine is running.
ABS is malfunctioning.
If th ere is an additional warning tone, EBD is malfunctioning.
Other driving sy stems and driving saf ety sy stems may also be malfunctioning. &
WARNING Thereisrisk of skidding if EBD or ABS is malfunctioning
If EBD or ABS is malfunctioning, the wheels could lock when braking
The steering capability and braking characteristics are thus se verely impaired. The braking dis tance may increase in
an emergency braking situation. In addition, other driving saf ety sy stems are switched off. #
Drive on carefull y. #
Have the brake sy stem checked immediately at a qualified specialist workshop. #
Drive on carefully. #
Obser vethe messages on the multifunction displa y. #
Consult a qualified specialist workshop.
÷ ESP ®
wa rning lamp flashes The
yellow ESP ®
wa rning lamp flashes while theve hicle is in motion.
At least one wheel and tyre assembly has reached its traction limit (→ page182). #
Adapt your driving style to suit thero ad and weather conditions. Display messages and
warning/indicator lamps 527

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
6 Re stra int sy stem warning
lamp The
redre stra int sy stem warning lamp is lit while the engine is running.
The restra int sy stem is faulty (→ page 32). &
WARNING Risk of inju ryor fata l injury due toa malfunction in there stra int sy stem
If th ere stra int sy stem is malfunctioning, restra int sy stem components may be triggered unintentionally or might not
be triggered at all in theeve nt of an accident. This may af fect the seat belt tensioner or airbag, forex ample. #
Have there stra int sy stem checked and repaired immediately at a qualified specialist workshop. #
Drive on carefully. #
Obser vethe messages on the multifunction displa y. #
Consult a qualified specialist workshop immediatel y. Seat belt
Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
7 Seat belt warning lamp
lights up The
red seat belt warning lamp will light up once the engine has star ted.
In addition, a warning tone may sound.
The seat belt warning lamp reminds the driver and front passenger tofast entheir seat belts. #
Fasten your seat belt (→ page37).
If yo u ha veplaced objects on the front passenger seat, the seat belt warning lamp may remain lit. Display messa
ges and warning/indicator lamps 531