Mercedes-Benz. These batteries provide
increased impact protection to prevent vehicle
occupants from suffering acid burns should the
battery be damaged in the event of an accident.
In order for the battery to achieve the maximum
possible service life, it must always be suffi-
ciently charged.
Like other batteries, the vehicle battery may
discharge over time if you do not use the vehicle.
In this case, have the battery disconnected at a
qualified specialist workshop. You can also
charge the battery with a charger recommended
by Mercedes-Benz. Contact a qualified special-
ist workshop for further information.
Have the battery condition of charge checked
more frequently if you use the vehicle mainly for
short trips or if you leave it standing idle for a
lengthy period. Consult a qualified specialist
workshop if you wish to leave your vehicle
parked for a long period of time.
Remove the SmartKey if you park the vehicle
and do not require any electrical consumers.
The vehicle will then use very little energy, thus conserving battery power.
If the power supply has been interrupted, e.g. if
you reconnect the battery, you will have to:
Rset the clock; see the Digital Operator's Man-
ual
On vehicles with a multimedia system, the
time is set automatically.
Rreset the function for folding the exterior mir-
rors in/out automatically, by folding the mir-
rors out once (
Ypage 101).
Charging the battery
!
Only use battery chargers with a maximum
charging voltage of 14.8 V.
GWARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, open flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over a battery.
GWARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with skin, eyes or clothing. Do
not inhale any battery gases. Do not lean over
the battery. Keep children away from batter-
ies. Wash away battery acid immediately with plenty of clean water and seek medical atten-
tion.
GWARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
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 charge the battery using the jump-
starting connection point.
The jump-starting connection point is in the
engine compartment (
Ypage 285).
XOpen the hood.
XConnect 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 (
Ypage 285).
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.
If the warning and indicator lamps do not light up
on the instrument cluster when temperatures
are low, it is probably because the discharged
battery has frozen. In this case, you may neither
charge the battery nor jump-start the vehicle.
The service life of a thawed-out battery may be
shorter. The starting characteristics can be
impaired, particularly at low temperatures. Have
the thawed-out battery checked at a qualified
specialist workshop.
284Battery (vehicle)
Breakdown assistance
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:
RThe 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.
RYou may only jump-start the vehicle when the engine and exhaust system are cold.
ROnly jump-start from batteries with a 12 V voltage rating.
ROnly use jumper cables which have a sufficient cross-section and insulated terminal clamps.
RIf 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.
RMake sure that the two vehicles do not touch.
Make sure that:
Rthe jumper cables are not damaged.
Rwhen the jumper cables are connected to the battery, uninsulated sections of the terminal clamp
do not come into contact with other metal sections.
Rthe 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.
XApply the parking brake firmly.
XShift the transmission to position P.
XMake 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 0in the ignition lock and remove it
(
Ypage 123).
XSwitch off all electrical consumers, e.g. rear window defroster, lighting, etc.
XOpen the hood.
Position number Bidentifies the charged battery of the other vehicle or an equivalent jump-starting
device.
XSlide cover :of positive terminal ;in the direction of the arrow.
XConnect positive terminal ;on your vehicle to positive terminal =of donor battery Busing the
jumper cable, always begin with positive terminal ;on your own vehicle first.
XStart the engine of the donor vehicle and run it at idling speed.
286Jump-starting
Breakdown assistance
As soonas the vehicle has been loaded:
XPrevent the veh iclefrom rolling away by
applyin g the parking brake.
XShift the automat ictransmission to posi-
tion P.
XTurn the SmartKey to position 0inthe ignition
lock and remove it.
XSecure the veh icle.
Notes on 4MATIC vehicles
!
Vehicle swit h 4MATIC must not betowed
wit h either the front or the rear axle raised, as
doin g so willdamage the transmission.
If the veh iclehas transmission damage or dam-
age to the front or rear axle, have ittransported
on a transporter or trailer.
In the event ofdama ge to the electrical sys-
tem
If the battery isdefective, the automat ictrans-
mission will belocked inposition P. To shift the
automat ictransmission to position N, you must
pro vide power to the veh icle's electrical system
in the same way as when jump-starting
(
Ypage 285).
Have the veh icletransported on a transporter or
trailer.
Tow-starting (emergency engine
starting)
!
Vehicle swit h automat ictransmission must
not bestarted bytow-starting. This could oth-
erwise damage the transmission.
iYou can find information on "Jump-starting"
under (Ypage 285).
Fuses
Important safety notes
GWAR NING
If you man ipulate orbridge a faulty fuse or if
you replace it with a fuse with a higher amper-
age, the electr iccables could beoverloaded.
This could result ina fire. There isa risk of an
acc iden t and injury.
Alwa ys replace faulty fuses with the specified
new fuses having the correct amperage.
Blo wn fuses must bereplaced with fuses of the
same rating, which you can recognize bythe
color and value. The fuse ratings are listed inthe
fuse allocation chart.
The fuse allocation chart is located in the vehicle
tool kit in the stowage compartment under the
trunk floor (
Ypage 277).
If a ne wlyinserted fuse also blows, have the
cause traced and rectified at a qualified special-
ist workshop, e.g. an authorized Mercedes-Benz
Center.
!Only use fuses that have been approved for
Mercedes-Benz vehicles and which have the
correct fuse rating for the system concerned.
Otherwise, components or systems could be
damaged.
!Make sure that no moisture can enter the
fuse box when the cover isopen.
!When closing the cover, make sure that it is
lying correctly on the fuse box. Moisture seep-
ing inor dirt could otherwise impair the oper-
ation of the fuses.
The fuses in your vehicle serve to closedown
faulty circuits. Ifa fuse blows, all the compo-
nents on the circuit and their functions stop
operating.
Before changing a fuse
Pay attention to the important safety notes
(Ypage 290).
XSwit ch off the engine.
XSwitch off all electrical consumers.
XMake sure that the ignition is switched off
(Ypage 123).
or
XWhen using the SmartKey, turn the SmartKey
to position 0in the ignition lock and remove it
(
Ypage 123).
XSecure the vehicle against rolling away
(Ypage 141).
All indicator lamps in the instrument cluster
must be off.
290Fuses
Breakdown assistance
The tire pressure monitor has a yellow warning
lamp in the instrument cluster for indicating
pressure loss or a malfunction. Whether the
warning lamp flashes or lights up indicates
whether a tire pressure is too low or the tire
pressure monitor is malfunctioning:
Rif the warning lamp is lit continuously, the tire
pressure on one or more tires is significantly
too low. The tire pressure monitor is not mal-functioning.
Rif the warning lamp flashes for around a
minute and then remains lit constantly, the
tire pressure monitor is malfunctioning.
In addition to the warning lamp, a message
appears in the multifunction display. Observe
the information on display messages
(
Ypage 221).
It may take up to ten minutes for a malfunction of the tire pressure monitor to be indicated. A
malfunction will be indicated by the tire pres-
sure warning lamp flashing for approximately
one minute and then remaining lit. When the
malfunction has been rectified, the tire pressure
warning lamp goes out after a few minutes of
driving.
The tire pressure values indicated by the on-
board computer may differ from those meas-
ured at a gas station with a pressure gauge. The
tire pressures shown by the on-board computer
refer to those measured at sea level. At high
altitudes, the tire pressure values indicated by a
pressure gauge are higher than those shown by the on-board computer. In this case, do not
reduce the tire pressures.
The operation of the tire pressure monitor can
be affected by interference from radio transmit-
ting equipment (e.g. radio headphones, two-way
radios) that may be being operated in or near the vehicle.
Checking the tire pressure electroni-
cally
XMake sure that the SmartKey is in position 2
in the ignition lock (Ypage 123).
XPress the =or; button on the steering
wheel to select the Servicemenu.
XPress the9or: button to select
Tire Pressure.
XPress the abutton.
The current tire pressure of each tire is shown
in the multifunction display. If the vehicle has been parked for over
20 minutes, the
Tire pressures will be
displayed after driving a few minutesmessage appears.
After a teach-in process, the tire pressure mon-
itor automatically detects new wheels or new
sensors. As long as a clear allocation of the tire
pressure value to the individual wheels is not
possible, theTire
PressureMonitorActivedisplay message is shown instead of the tire
pressure display. The tire pressures are already
being monitored.
If an emergency spare wheel is mounted, the
system may continue to show the tire pressure
of the wheel that has been removed for a few
minutes. If this occurs, note that the value dis-
played for the position where the spare wheel is
mounted is not the same as the current tire
pressure of the emergency spare wheel.
Tire pressure monitor warning mes-
sages
If the tire pressure monitor detects a pressure
loss in one or more tires, a warning message is
shown in the multifunction display. The yellow
tire pressure warning lamp then lights up.
RIf the Correct Tire Pressuremessage
appears in the multifunction display, the tire
pressure in at least one tire is too low. The tire
pressure must be corrected when the oppor-
tunity arises.
RIf the Check Tiresmessage appears in the
multifunction display, the tire pressure in one
or more tires has dropped significantly. The
tires must be checked.
RIf the WarningTireMalfunctionmessage
appears in the multifunction display, the tire
pressure in one or more tires is dropping sud-
denly. The tires must be checked.
Observe the instructions and safety notes in the
display messages in the "Tires" section
(
Ypage 221).
If the wheel positions on the vehicle are rotated,
the tire pressures may be displayed for the
wrong positions for a short time. This is rectified after a few minutes of driving, and the tire pres-
sures are displayed for the correct positions.
Tire pressure301
Wheels and tires
Z