2018 MERCEDES-BENZ S-CLASS CABRIOLET BATTERY

Wear saf etygl asses.
Ke ep children away.
Obser vethis Opera tor's Manual.
If yo udo not intend touse theve hicle over an
ex tended pe riod of time:
RAc tivate standby mode, or
RConnect the battery toa batte rycharge r
appr ovedby Mercedes-Benz, or
RConsult a qualified specialist workshop to
disconnect the battery
St arting assist ance andcharging the12 V
battery
Ve hicles with a lithium-ion battery
#When charging the battery and during start‐
ing assis tance, al ways use the jump-s tart
connection point in the engine compartment.
* NO
TEDama getothe battery from over‐
vo ltage
When charging using a batte rycharge r with‐
out a maximum charging voltage, the battery
or the on-board electronics may be damaged.
#Only use battery charge rs with a maxi‐
mum charging voltage of 14.4 V.
* NO
TEShor tening the service life of the
battery bycharging the battery at low
te mp eratures
Charging the battery at very low temp era‐
tures may shor tenth e service life of the bat‐
te ry and ha vea negative ef fect on starting.
#Do not charge the battery at very low
te mp eratures.
All other vehicles
#When charging the battery and during start‐
ing assis tance, al ways use the jump-s tart
connection point in the engine compartment.
* NO
TEDamaging the battery thro ugh
ove rvoltage
When charging using a batte rycharge r with‐
out a maximum charging voltage, the battery
or theve 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.
350
Breakdown assis tance

#Make surethat the positive term inal of
th e connected battery does not come
into conta ct withvehicle parts.
#Ne ver place me tal objects or tools on a
batter y.
#When connecting and disconnecting the
batter y,yo u must observ eth e descri‐
bed order forth e battery clamps.
#When giving starting assis tance, al ways
make sure that you only connect bat‐
te ry term inals with identical polarity.
#During starting assis tance, you must
observ eth e described order for con‐
necting and disconnecting the jumper
cables.
#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.
#Av oid fire , open flames, creating spar ks
and 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.
Ifth 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.
& 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, batte rygas may be released.
#Alw aysth aw a frozen batte ryout firs t
before charging it or per form ing start‐
ing assis tance.
The service li feof a battery that has been
th awe d may be dramatically shor tened. It is
recommended that you ha veathaw ed bat‐
te ry checked at a qualified specialist workshop.
All vehicles
* NO
TEDama gecaused bynumerous or
ex tended attem ptsto start the engine
Nume rous or extended attem ptsto start the
engine may damage the catalytic con verter
due tonon-combu sted fuel.
#Av oid numerous and extended attem pts
to start the engine.
Obser vethefo llowing points during starting
assis tance and when charging the battery:
ROnly use undamaged jumper/charging
cables with a suf ficient cross-section and
insula tedte rm inal clamps.
RNon- insulated parts of thete rm inal clamps
must not come into con tact wi thother me tal
parts while the jumper/charging cable is
connected tothe battery/jump-s tart connec‐
tion point.
Breakdown assis tance 351

RThe jumper/charging cable must not come
into contact with any parts which may move
when the engine is running.
RAlw ays make sure that nei ther you nor the
battery is elect rostatically charge d.
RKe ep away from fire and open flames.
RDo not lean overth e batter y.
RWhencharging: only use battery charge rs
te sted and appr oved byMercedes-Benz, and
please read the battery charge r's operating
instructions before charging the batter y.
Obser vethe additional following points during
st arting assis tance:
RSt arting assis tance may only be pr ovided
using batteries with a nominal voltage of
12 V.
RThe vehicles must not touch.
RGa soline engine: onlyaccept starting assis‐
ta nce if the engine and exhaust sy stem are
cold.
#Secure theve hicle byapplying the electric
parking brake.
#Au tomatic transmission: shiftthe transmis‐
sion toposition B.
#Make sure that the ignition and all electrical
consumers are switched off.
#Open the hood.
#Ve hicles with ground point co ver:tur n
sc rews 2 from ground point co ver1 anti-
clockwise and remo veground point co ver
1.#Slide co ver3 of positive clamp 4onthe
jump-s tarting connection point in the direc‐
tion of the ar row.
#Connect positive clamp 4onyour vehicle to
positive pole of the donor battery using the
jumper/charging cable. Alw ays begin with
positive clamp 4onyour ow nve hicle firs t.
352
Breakdown assist ance

#Duringthest arting assist ance proce‐
dure: start the engine of the donor vehicle
and run at idle speed.
#Connect the negative pole of the donor bat‐
te ry and ground po int5 ofyour ow nve hicle
by using the jumper/charging cable. Begin
with the donor battery firs t.
#Du ring starting assist ance:start the
engine of your ow nve hicle.
#During thech arging process: start the
ch arging process.
#During starting assist ance:letthe engines
ru nfo r se veral minutes.
#During starting assist ance:before discon‐
necting the jumper cable, switch on an elec‐
trical consumer in your ow nve hicle, e.g. the
re ar wind owheater or lighting.
When thest arting assis tance/charging process
is compl ete:
#Fir st,re mo vethe jumper/charging cable
from ground point 5and negative pole of
th e donor batter y,then from positive clamp
4 and positive pole of the donor batter y.
Begin eachtime with the conta cts onyour
ow nve hicle firs t.
#Af terre moving the jumper/charging cable,
close co ver3 of positive clamp 4.
#Vehicles with ground point co ver:replace
ground point co ver1 and turn scr ews2
clockwise.
Yo u can obtain fur ther information on starting
assis tance at any qualified specialist workshop.
Re placing the 12V battery
#Obser vethe no tes on the12 V battery
(→page 348).
Mercedes-Benz recommends that you ha vethe
12 V battery replaced at a qualified specialist
wo rkshop, e.g. at an authorized Mercedes-Benz
Center.
Obser vethefo llowing no tes if youwa ntto
re place the battery yourself:
RAlw aysre place a defective battery with a bat‐
te ry which meets the specific vehicle require‐
ments.
RCar ryove r de tach able parts, such as vent
hoses, elbow fitting or term inal co vers from
th e battery being replaced.
RMake sure that theve nt hose is al ways con‐
nected tothe original opening on the side of
th e batter y.
Ins tall any existing or supplied cell caps.
Otherwise, gases or battery acid could
escape.
RMake sure that de tach able parts are recon‐
nected in the same way.
Tow starting or towing away
Perm itted towing me thods
Mercedes-Benz recommends transporting your
ve hicle in the case of a breakdown, rath er than
to wing it away.
* NO
TEDama getotheve hicle due to tow‐
ing away incor rectly
#Obser vethe instructions and no tes on
to wing away.
Breakdown assis tance 353

Perm itted towing me thods
Ve hicle equipment/to wing
me thod
Bo th axles on thegr oundFront axle raisedRe ar axle raised
Ve hicles with automatic transmis‐
sion Ye
s, maximum 31miles (50 km) at
31 mp h (50 km/h) No
Yes, if thesteering wheel is fixe d in
th e center position with a steering
wheel loc k.
4MATIC vehicles Yes, maximum 31miles (50 km) at
31 mp h (50 km/h) No
No
Towing wit h araised axle: towing should be
per form ed byato wing compan y.
Towing theve hicle with bo thaxles on the
gr ound
#Obser vethe no tes on the permitted towing
me thods(→page 353).
#Make sure that the battery is connected and
ch arge d. When
the battery is dischar ged:
Rthe engine cannot bestar ted.
Rth e electric parking brake cannot bereleased
or applied.
Rth e automatic transmission cann otbe shif ted
to position iorj.
% Ifth e automatic transmission cannot be shif‐
te dto position i, orthe multifunction dis‐
play in the instrument clus ter does not show anything, ha
vetheve hicle transpor tedaw ay
(
→page 356). A towing vehicle with lifting
equipment is requiredforve hicle transpor ta‐
tion.
354 Breakdown assist ance

Displaymessages
Possible causes/consequences and MSolutions
?
*Thefan mo tor is defective.
#Av oiding high loads on the engine, drive on tothe nearest qualified specialist workshop. In doing so, ensure that
th e coolant temp erature display remains below 248 °F (120 °C).
#
Stop Vehicle See Opera-
tor's Manual *T
he battery is no longer being charge d and the battery charge leve l is too lo w.
* NO
TEPossible engine damage if you continue dr iving#Do not continue dr iving under any circum stances.
#Consult a qualified specialist workshop.
#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.
#Consult a qualified specialist workshop.
#
Start Engine See Opera-
tor's Manual *T
he engine is off and the battery charge leve l is too lo w.
#Switch off electrical consumers that are not required.
#Leavethe engine running for a few minutes, or drive for a longer dis tance.
The battery charge s.
428
Display messages and warning/indicator lamps

Displaymessages
Possible causes/consequences and MSolutions
#
Stop Vehicle Leave Engine
Running*T
he battery charge leve l is too low and must be charge d.
#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.
#Lea veengine running.
#Wa it until the display message disappears before pulling away.
4
Check Engine Oil At Next
Refue ling *T
he engine oil le vel has dropped tothe minimum le vel.
* NO
TEEngine damage causedbydriving with insuf ficient engine oil#Av oid long journe yswith insuf ficient engine oil.
#Check the engine oil le vel when next refueling.
To p up the engine oil (
→page 331).
No tes on engine oil (
→page 398).
8
Gas Cap Loose *T
here has been pressure loss in the fuel sy stem. The fuel filler cap is not closed cor rectly or the fuel sy stem is
leaking.
#Close the fuel filler cap.
#If th e fuel filler cap was already proper lyclosed: consult a qualified specialist workshop.
Display messages and warning/indicator lamps 429

SmartKey
Displaymessages
Possible causes/consequences and MSolutions
Â
Obtain a New Key*T
he SmartK eyneeds tobe replaced.
#Visit a qualified specialist workshop.
Â
Replace Key Battery *T
he SmartK eybattery is dischar ged.
#Re place the battery .
Â
Key Not Detected (white
display message) *T
he SmartK eyis cur rently und etected.
#Change the location of the SmartK eyintheve hicle.
#Ifth e SmartK eyisstill not recognized, start the engine with the SmartK eyinthestow age compartment .
434
Display messages and warning/indicator lamps