2016 MERCEDES-BENZ S CLASS hood open

ing the vehicle or charging the battery, gases
can escape from the battery. There is a risk of
an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
! Only use battery chargers with a maximum
charging voltage of 14.8 V.
All vehicles:
! Only charge the battery using the jump-
starting connection point.
The jump-starting connection point is in the
engine compartment ( Y
page 376).X
Open the hood. X
Connect the battery charger to the positive
terminal and ground point in the same order
as when connecting the donor battery in the
jump-starting procedure ( Y
page 376).
Keep away from fire and open flames. Do not
lean over a battery. Never charge the battery if it
is still installed in the vehicle, unless you use a
battery charger which has been tested and
approved by Mercedes-Benz. A battery charger
unit specially adapted for Mercedes-Benz vehi-
cles and tested and approved by Mercedes-
Benz is available as an accessory. It permits the
charging of the battery in its installed position.
Contact an authorized Mercedes-Benz Center
for further information and availability. Read the
battery charger's operating instructions before
charging the battery.
All vehicles except Mercedes-AMG vehicles:
if the indicator/warning lamps in the instrument
cluster do not light up at low temperatures, it is
very likely that the discharged battery has fro-
zen. In this case you may neither jump-start the
vehicle nor charge the battery. The service life of
a thawed-out battery may be shorter. The start-
ing characteristics can be impaired, particularly
at low temperatures. Have the thawed- out bat -
t ery checked at a qualified specialist workshop.
Mercedes-AMG vehicles: at low temperatures,
do not charge a battery which has been removed
using a battery charger. Allow the battery to
warm up gently first, if necessary. Otherwise,
the service life can be shortened and the start-
ing characteristics impaired, especially at low
temperatures.
PLUG-IN HYBRID vehicles: if the battery
charge is sufficient, the high-voltage battery can
also supply the 12 V battery. This only happens if the condition of charge of the 12 V battery
requires this, e.g. after using electrical consum-
ers for an extended period with the engine
switched off. As the on-board voltage is contin-
uously monitored this can also be performed
when the engine is switched off. The condition of
charge of the 12 V battery and the on-board
voltage are thereby kept stable for a longer
period.
Battery (vehicle) 375
Breakdown assistance Z

Do not start the vehicle using a rapid charging device. If your vehicle's battery is discharged, the
engine can be jump-started from another vehicle or from a second battery using jumper cables.
Observe the following points: R
The battery is not accessible in all vehicles. If the other vehicle's battery is not accessible, jump-
start the vehicle using a second battery or a jump-starting device. R
You may only jump-start the vehicle when the engine and exhaust system are cold. R
All vehicles except Mercedes-AMG vehicles: do not start the engine if the battery is frozen. Let
the battery thaw first. R
Only jump-start from batteries with a 12 V voltage rating. R
Only use jumper cables which have a sufficient cross-section and insulated terminal clamps. R
If the battery is fully discharged, leave the battery that is being used to jump-start connected for
a few minutes before attempting to start. This charges the battery slightly. R
Make sure that the two vehicles do not touch.
Make sure that: R
the jumper cables are not damaged. R
when the jumper cables are connected to the battery, uninsulated sections of the terminal clamp
do not come into contact with o ther metal sections.R
the jumper cables cannot come into contact with parts which can move when the engine is
running, such as the V-belt pulley or the fan. X
Secure the vehicle by applying the electric parking brake. X
Shift the transmission to position P .X
Make sure that the ignition is switched off. All indicator lamps in the instrument cluster must be
off. When using the SmartKey, turn the SmartKey to position 0 in the ignition lock and remove it
( Y
page 162). X
Switch off all electrical consumers, e.g. rear window defroster, lighting, etc. X
Open the hood.
Example: ground point cover X
Turn fasteners C one

Fuse box in the engine compartment
G WARNIN G
When th e hoo d is open and th e windshield
wiper s are set in motion , you can be injured by
th e wiper linkage. Ther e is a ris k of injury.
Always switch off th e windshield wiper s and
th e ignition before opening th e hood.
! Mak e sure that no moisture can ente r th e
fus e box when th e cover is open .
! When closin g th e cover , mak e sure that it is
lyin g correctly on th e fus e box . Moistur e seep -
ing in or dirt could otherwise impair th e oper -
ation of th e fuses.
X
Open th e hoo d ( Y
page 352).X
To open : release retaining clamps C and
remove cover D .
X
Use a dry cloth to remove any moisture from
th e fus e box .X
Undo screws