Page 329 of 506

Battery disconnection periods
The ASSYST PLUS service inter val display
can only calculate the service due da tewhen
th e batte ryis connected.
#Notedown the service due date displa yed in
th e Instrument Display before disconnecting
th e battery (
→page 326).
Engine compartment
Ac tive hood (pedestrian pr otection)
Operation of the active hood (pedestrian pro‐
te ction)
In cer tain accident situations, therisk of injury
to pedestrians can be reduced bythe actuation
of the active hood. The rear area of the engine
hood is raised byappr oximately 85 mm.
Fo rth e drive tothewo rkshop, reset the trig‐
ge red active hood yourself. Ifth e active hood
has been triggered, pedestrian pr otection may
be limited.
A qu alified specialist workshop must re-ins tate
th e full functionality of the active hood. The active hood is not
available in all countries.
Re setting the active hood
&
WARNING Risk of burn s from hot com‐
ponent parts in the engine compartment
Cer tain component parts in the engine com‐
partment can be very hot, e.g. the engine,
th e cooler and parts of theex haust sy stem.
#Let the engine cool down and only
to uch the component parts described
as follo ws .
#With your hand flat, push down active hood
1 inthe area around the hinges on bo th
sides (ar rows).
The engine hood must engage in position.
#If th e active hood can be raised slightly at
th ere ar passenger compartment in the area
of the hinges, repeat thestep until it engages
cor rectly in position.
Opening/closing the hood
&
WARNING Risk of accident if the engine
hood is unlatched while driving
An unloc ked engine hood may open up when
th eve hicle is in motion and block your vie w.
#Never unlatch the engine hood while
driving.
#Before every trip, ensure that the
engine hood is latched.
Maintenance and care 327
Page 330 of 506

&WARNING Risk of accident and injury
when opening and closing the engine
hood
When opening or closing the engine hood, it
may suddenly drop into the end position.
There is a risk of injury for an yone in the
engine hood's range of mo vement.
#Only open or close the engine hood
when there are no persons in the
engine hood's range of mo vement.
&
WARNING Danger of burn s when open‐
ing the hood
If yo u open the hood when the engine has
ove rheated or during a fire inthe engine
compartment, you could come into contact
wit h hot gases or other escaping operating
fl uids.
#Before opening the hood, allow the
engine tocool down.
#Intheeve nt of a fire inthe engine com‐
partment, keep the hood closed and
call thefire service.
&
WARNING Risk of injury duetomoving
parts
Cer tain components in the engine compart‐
ment may continue tomo veor suddenly
mo veagain even af terth e ignition has been
switched off, e.g. the cooler fan.
Make sure of thefo llowing before per form ing
ta sks in the engine compartmen t:
#Switchthe ignition off.
#Ne verto uch the danger zone sur round‐
ing moving co mponent parts, e.g. the
ro tation area of thefa n.
#Re mo vejewe lry and watches.
#Keep items of clo thing and hair away
from moving parts.
& WARNING Risk of injury fromtouching
co mp onent parts under voltage
The ignition sy stem and the fuel injection
sy stem workunder high voltage. If youto uch
co mp onent parts which are under voltage,
yo u could receive an electric shoc k.
#Neverto uch co mponent parts of the
ignition sy stem or the fuel injection sys‐
te m when the ignition is switched on.
&
WARNING Risk of burn s from hot com‐
ponent parts in the engine compartment
Cer tain component parts in the engine com‐
partment can be very hot, e.g. the engine,
th e cooler and parts of theex haust sy stem.
#Let the engine cool down and only
to uch the component parts described
as follo ws .
328
Maintenance and care
Page 331 of 506
&WARNING Risk of injury from usingthe
windshield wipers while the engine hood
is open
When the engine hood is open and the wind‐
shield wipers are set in motion, you can be
trapped bythe wiper linkage.
#Alw ays switch off the windshield wipers
and ignition before opening the engine
hood.
#To open: pull lever1 torelease the hood.#Push le ver1 ofthe hood catch upwards
and lift the hood byappr oximately 15in
(40 cm).
#To close: lowe rth e hood and let it fall from a
height of appr oximately 8 in (20 cm).
#Ifth e hood can still be lif ted slightl y,open
th e hood again and close it with a little more
fo rc e until it engages cor rectl y.
Maintenance and care 329
Page 332 of 506

Engine oil
Checkingthe engine oil le vel using the oil
dip stick
&
WARNING Risk of burn s from hot com‐
ponent parts in the engine compartment
Cer tain component parts in the engine com‐
partment can be very hot, e.g. the engine,
th e cooler and parts of theex haust sy stem.
#Let the engine cool down and only
to uch the component parts described
as follo ws .
Depending on the engine, the oil dipstick may be
ins talled in the engine compartment in dif fere nt
locations.
Wa iting time before checking the oil le vel:
REngine at normal operating temp erature: five
minutes.
REngine not at normal operating temp erature
(e.g. the engine was only star ted brief ly): 30
minutes.
#Pa rk theve hicle on a flat sur face.
#Re mo veoil dipstick 1and wipe off.
#Slowly slide oil dipstick 1into the guide
tube tothestop, and take it out again af ter
appr oximately thre e seconds.
ROil le vel is cor rect: oil le vel is between 2
and 3.
ROil le velto o low: oil le vel is at 3or
belo w.
ROil le velto o high: oil le vel is abo ve2.
#Ifth e oil le vel is too lo w,add 1.1 US qt (1 l) of
engine oil.
#If th e oil le vel is too high, drain off excess
engine oil. Consult a qualified specialist
wo rkshop.
Ad ding engine oil
&
WARNING Risk of burn s from hot com‐
ponent parts in the engine compartment
Cer tain component parts in the engine com‐
partment can be very hot, e.g. the engine,
th e cooler and parts of theex haust sy stem.
#Let the engine cool down and only
to uch the component parts described
as follo ws .
&
WARNING Risk offire and injury from
engine oil
If engine oil comes into con tact wi thhot
component parts in the engine compart‐
ment, it may ignite.
330 Maintenance and care
Page 333 of 506

#Make surethat no engine oil is spilled
next tothefiller opening.
#Allow the engine tocool off and thor‐
oughly clean the engine oil from compo‐
nent parts before starting theve hicle.
* NO
TEEngine damage causedbyan
incor rect oil filter, incor rect oil or addi‐
tives
#Do not use engine oils or oil filters
which do not cor respond tothe specifi‐
cations explicitly prescribed forth e
service inter vals.
#Do not alter the engine oil or oil filter in
order toachie velonger change inter vals
th an prescri bed.
#Do not use additives.
#Follow the instructions in the service
inter val display rega rding the oil
ch ange.
* NO
TEDama gecaused bytopping up too
much engine oil
Ad ding too much engine oil can cause dam‐
age tothe engine or the catalytic con verter.
#Ha ve excess engine oil remo ved at a
qu alified specialist workshop.
#Tu rn cap 1counter-clockwise and remo ve
it.
#Ad d engine oil.
#Replace cap 1and turn it clockwise as far
as it will go.
#Check the oil le vel again (→page 330).
Checking coolant le vel
&
WARNING Risk of burn s from hot com‐
ponent parts in the engine compartment
Cer tain component parts in the engine com‐
partment can be very hot, e.g. the engine,
th e cooler and parts of theex haust sy stem.
#Let the engine cool down and only
to uch the component parts described
as follo ws .
&
WARNING Danger of burn s from hot
coolant
The engine cooling sy stem is pressurized,
particularly when the engine is warm. If you
Maintenance and care 331
Page 334 of 506

openthe cap, you could bescalded byhot
coolant spr aying out.
#Let the mo tor cool down before opening
th e cap.
#When opening the cap, wearglove s and
pr otective eyew ear.
#Slowly turn the cap half a turn toallow
pressure toescape.
#Park theve hicle on a flat sur face.
#Check the coolant temp erature display in the
instrument clus ter.
The coolant temp erature must be below
15 8 °F (70 °C).
#Slowly turn cap 1counter-clockwise to
re lie ve ove rpressure.
#Continue turning cap 1counter-clockwise
and remo veit.
The coolant le vel is cor rect:
RIfth e engine is cold, up tomar ker bar 2
RIfth e engine is warm, up to0.6 in (1.5 cm)
ove r mar ker bar 2
#If necessar y,add coolant that has been
appr ovedby Mercedes-Benz.
RFurther information on coolant (→page 397)
Re filling the windshield washer sy stem
&
WARNING Risk of burn s from hot com‐
ponent parts in the engine compartment
Cer tain component parts in the engine com‐
partment can be very hot, e.g. the engine,
th e cooler and parts of theex haust sy stem.
#Let the engine cool down and only
to uch the component parts described
as follo ws .
&
WARNING Danger of burn s when open‐
ing the engine hood
If yo u open the engine hood when the engine
has overheated or during a fire inthe engine
compartment, you could come into contact
with hot gases or other escaping operating
fl uids.
#Before opening the engine hood, allow
th e engine tocool down.
#Intheeve nt of a fire inthe engine com‐
partment, keep the engine hood closed
and call thefire service.
332
Maintenance and care
Page 335 of 506

&WARNING ‑ Risk of fire and injury from
windshield washer concentrate
Wi ndshield 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 windshield washer
concentrate spills out next tothefiller
opening.
#Re mo vecap 1bytheta b.
#Ad dwa sher fluid.
Cleaning and care
Informa tiononwashing theve hicle in a car
wa sh
&
WARNING Risk of accident due to
re duced braking ef fect af terwa shing the
ve hicle
The braking ef fect is reduced af terwa shing
th eve hicle.
#Afterth eve hicle has been washed,
brake carefully while paying attention to
th e traf fic conditions until the braking
ef fect has been ful lyrestored.
To avo id damage to yourvehicle when using a
car wash, ensure thefo llowing beforehand:
RAc tive Dis tance Assist DISTRONIC and the
HOLD function are deactivated.
RThe 360° Camera or there ar view camera is
switch ed off.
RThe side windo wsand sliding sunro of are
comple tely closed.
Maintenance and care 333
Page 336 of 506

RThe blowerfo rth eve ntilation/heating is
switched off.
RThe windshield wiper switch is in position
g.
RIn car washes with a towing mechanism: neu‐
tral iis engaged.
RThe SmartK eyis at a dis tance of at least
10 ft(3 m) away from theve hicle, otherwise
th eta ilgate could open unin tentionally.
% If, af terth e car wash, youre mo vethewa x
from the windshield and wiper rubber, this
will pr event smearing and reduce wiper
noise.
Information on using a po werwa sher
&
WARNING Risk of accident when using
high-pressure cleaning equipment wi th
ro und-s pray nozzles
The wate r jet from a round-s pray nozzle (dirt
grinder) may cause damage totires and sus‐
pension components that is not visible.
Components damaged in this wa yma yfa il
unexpec tedly.
#Do not use high-pressure cleaning
equipment wi thround-spr aynozzles to
clean your vehicle.
#Damaged tires or suspension compo‐
nents must be replaced immediatel y.
Toavo id damage to yourvehicle, obser vethefo l‐
lowing when using a po werwa sher:
RKeep the SmartK eyat least 10ft(3 m) away
from theve hicle. Otherwise theta ilgate
could open unin tentional ly.
RMaintain a dis tance of at least 11.8 in
(30 cm) totheve hicle.
RVe hicles with deco rative foil: parts of your
ve hicle are co vered with a decorative foil.
Maintain a dis tance of at least 27.6 in
(70 cm) between thefo il-c ove red parts of the
ve hicle and the nozzle of the po werwa sher.
Mo vethe po werwa sher cleaner nozzle
around whilst cleaning.
RObser vethe information on the cor rect dis‐
ta nce in the equipment manufacturer's oper‐
ating instructions.
RDo not point the nozzle of the po werwa sher
directly at sensitive parts such as tires, slits,
electrical component parts, batteries, light
sources and ventilation slot s.
Washing the vehicle byhand
Obser vethe legal requirements, e.g. in a number
of countries, washing byhand is only permitted
in specially designated washing areas.
#Use a mild cleaning agent, e.g. car shampoo.
#Wa shtheve hicle with luk ewarmwate r using
a soft car sponge. When doing so, do not
ex pose theve hicle todirect sunlight.
#Carefully hose theve hicle off with water and
dry using a chamois. Take care not topoint
th ewate r jet directly towa rdsth e air inlet
grille.
334 Maintenance and care