The vehicle will then use very little energy, thus
conserving battery power.
If the power supply has been interrupted, e.g. ifyou reconnect the battery, you will have to:
Rset the clock; see the Digital Operator's Man-
ual
On vehicles with a multimedia system and
navigation system, the clock is set automati-
cally.
Rreset the function for folding the exterior mir-
rors in/out automatically, by folding the mir-
rors out once (
Ypage 108).
Charging the 12 V battery
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 use battery chargers with a maximum
charging voltage of 14.8 V.
!Only charge the battery using the jump-
starting connection point.
The jump-starting connection point is in the
engine compartment (
Ypage 338).
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 338).
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, at low temperatures, the indicator lamps/
warning lamps in the instrument cluster do not
light up, it is highly likely that the discharged
battery has frozen. 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 starting characteristics can be
impaired, particularly at low temperatures. Have
the thawed-out battery checked at a qualified
specialist workshop.
Jump-starting
For the jump-starting procedure, use only the jump-starting connection point in the engine com-
partment, consisting of a positive terminal and a ground point.
GWARNING
Battery acid is caustic. There is a risk of injury.
338Jump-starting
Breakdown assistance
Avoid contact with skin, eyes or clothing. Do not inhale any battery gases. Do not lean over the
battery. Keep children away from batteries. Wash away battery acid immediately with plenty of
clean water and seek medical attention.
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 ven-
tilation while charging and jump-starting. Do not lean over a battery.
GWARNING
During the charging process, a battery produces hydrogen gas. If a short circuit occurs or sparks
are created, the hydrogen gas can ignite. There is a risk of an explosion.
RMake sure that the positive terminal of a connected battery does not come into contact with
vehicle parts.
RNever place metal objects or tools on a battery.
RIt is important that you observe the described order of the battery terminals when connecting
and disconnecting a battery.
RWhen jump-starting, make sure that the battery poles with identical polarity are connected.
RIt is particularly important to observe the described order when connecting and disconnecting
the jumper cables.
RNever connect or disconnect the battery terminals while the engine is running.
GWARNING
A discharged battery can freeze at temperatures below freezing point. When jump-starting 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.
!Vehicles with a gasoline engine: avoid repeated and lengthy starting attempts. Otherwise, the
catalytic converter could be damaged by non-combusted fuel.
If the indicator/warning lamps do not light up at low temperatures, it is very likely that the dis-
charged battery has frozen. 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 starting characteristics can be
impaired, particularly at low temperatures. Have the thawed-out battery checked at a qualified
specialist workshop.
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 de vice.
RVehicles with a gasoline engine:only jump-start the vehicle when the engine and exhaust
system are cold.
RDo not start the engine if the battery is frozen. Let the battery thaw first.
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.
Jump-starting339
Breakdo wn assis tance
Z
Check wheels and tires for damage at least once
a month. Check wheels and tires afterdriving
off-road or on rough roads. Damaged wheels
can cause a loss of tire pressure. Pay particular
attention to damage such as:
Rcuts inthe tires
Rpunctures
Rtears inthe tires
Rbulges on tires
Rdeformation or severe corrosion on wheels
Regularly check the tire tread depth and the
condition of the tread across the whole width of
the tire (
Ypage 347). Ifnecessary, turn the
front wheels to full lock inorder to inspect the
inner sideof the tire surface.
All wheels must have a valve cap to protect the valve against dirtand moisture. Do not mount
anything onto the valve other than the standard
valve cap or other valve caps approved by
Mercedes-Benz for your veh icle. Do not use any
other valve caps or systems, e.g. tire pressure
monitoring systems.
Regularly check the pressure of all the tires par-
ticularly prior to long tr ips.Adjust the tire pres-
sure as necessary (
Ypage 349).
Observe the notes on the emergency spare
wheel (
Ypage 372).
The service lifeof tires depends, among other
things, on the foll owing factors:
RDrivin g style
RTire pressure
RDistance covered
Notes on tire tread
GWAR NING
In suff icient tire tread willreduce tire traction.
The tire isno longer abletodissipat e water.
This means that on wet road surfaces, the risk
of hydroplaning increases, inparticular where
speed isnot adapted to suit the driving con-
dit ions. There isa risk of acc ident.
If the tire pressure istoo high or too low,tires
may exhibit different leve lsof wear at differ-
ent locations on the tire tread. Thus, you
should regularly check the tread depth and
the condition of the tread across the entire
widt h of all tires.
Minimum tire tread depth for:
RSummer tires: âin(3 mm)
RM+S tires: ãin(4 mm)
For safety reasons, replace the tires before
the legally prescribe d limit for the minimum
tire tread depth is reached.
Marking :shows where the bar indicator
(arrow) for tread wear isintegrated into the tire
tread.
Treadwear indicators (TWI) are required by law.
Six indicators are positioned on the tire tread.
They are vis ibleonce a tread depth of approx-
imately áin(1.6 mm) has been reached. Ifthis
is the case, the tire isso worn that it must be
replaced.
Selecting, mounting and replacing
tires
ROnly mount tires and wheels of the same type
and make.
Exception: it is permissible to install a differ-
ent type or make inthe event of a flat tire.
Observe here the "MOExtended tires (tires
wit h run-flat characteristics)" section
(
Ypage 332).
ROnly mount tires of the correct size onto the
wheels.
RBreak in new tires at moderate speeds for the
first 60 miles(100 km). They only reach their
full performance after this distance.
RDo not drive with tires which have too little
tread depth, as this significantly reduces the
traction on wet roads (hydroplaning).
RReplace the tires after six years at the latest,
regardless of wear.
Operation347
Wheels and tires
Z
Avoid tire pressures that are too high in all the
tires, including the spare wheel.
Overinflated tires may:
Rincrease the braking distance
Radversely affect handling
Rwear excessively and/or unevenly
Rhave an adverse effect on ride comfort
Rbe more susceptible to damage
Maximum tire pressures
:Example: maximum permissible tire pres-
sure
Never exceed the maximum permissible tire
inflation pressure. Always observe the recom-
mended tire pressure for your vehicle when
adjusting the tire pressure (
Ypage 349).
iThe actual values for tires are vehicle-spe-
cific and may deviate from the values in the
illustration.
Checking the tire pressures
Important safety notes
Observe the notes on tire pressure
(Ypage 349).
Information on air pressure for the tires on your
vehicle can be found:
Ron the Tire and Loading Information placard
on the B-pillar on the driver's side
Rin the tire pressure table in the fuel filler flap
Rin the "Tire pressure" section
Checking tire pressures manually
To determine and set the correct tire pressure,
proceed as follows:
XRemove the valve cap of the tire that is to be
checked.
XPress the tire pressure gage securely onto the
valve.
XRead the tire pressure and compare it to the
recommended value on the Tire and Loading
Information placard or the tire pressure table
(
Ypage 349).
XIf the tire pressure is too low, increase the tire
pressure to the recommended value.
XIf the tire pressure is too high, release air. To
do so, press down the metal pin in the valve,
using the tip of a pen for example. Then check
the tire pressure again using the tire pressure
checker.
XScrew the valve cap onto the valve.
XRepeat these steps for the other tires.
Tire pressure loss warning system
General notes
While the vehicle is in motion, the tire pressure
loss warning system monitors the set tire pres-
sure using the rotational speed of the wheels.
This enables the system to detect significant
pressure loss in a tire. If the speed of rotation of
a wheel changes as a result of a loss of pressure,
a corresponding warning message will appear in
the multifunction display.
You can recognize the tire pressure loss warning
by the Run Flat Indicator Active Press
'OK' to Restartmessage which appears in
the Servicemenu of the multifunction display.
Information on the message display can be
found in the "Restarting the tire pressure loss
warning system" section (
Ypage 353).
Important safety notes
The tire pressure warning system does not warn you of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
(
Ypage 349).
The tire pressure loss warning does not replace
the need to regularly check the tire pressure. An
even loss of pressure on several tires at the
352Tire pressure
Wheels and tires
same time cannot be detected by the tire pres-
sure loss warning system.
The tire pressure monitor is not able to warn you
of a sudden loss of pressure, e.g. if the tire is
penetrated by a foreign object. In the event of a
sudden loss of pressure, bring the vehicle to a
halt by braking carefully. Avoid abrupt steering
movements.
The function of the tire pressure loss warning
system is limited or delayed if:
Rsnow chains are mounted on your vehicle's
tires.
Rroad conditions are wintry.
Ryou are driving on sand or gravel.
Ryou adopt a very sporty driving style (corner-
ing at high speeds or driving with high rates ofacceleration).
Ryou are driving with a heavy load (in the vehi-cle or on the roof).
Restarting the tire pressure loss warn-
ing system
Restart the tire pressure loss warning system if
you have:
Rchanged the tire pressure
Rchanged the wheels or tires
Rmounted new wheels or tires
XBefore restarting, make sure that the tire
pressures are set properly on all four tires for
the respective operating conditions.
The recommended tire pressure can be found
on the Tire and Loading Information placard
on the B-pillar. Additionally, a tire pressure
table is attached to the fuel filler flap. The tire
pressure loss warning system can only give
reliable warnings if you have set the correct
tire pressure. If an incorrect tire pressure is
set, these incorrect values will be monitored.
XAlso observe the notes in the section on tire
pressures (Ypage 349).
XMake sure that the SmartKey is in position 2
in the ignition lock (Ypage 138).
XPress the =or; button on the steering
wheel to select the Servicemenu.
XPress the9or: button to select
Tire Pressure.
XPress the abutton.
The Run Flat Indicator Active Press
'OK' to Restartmessage appears in the
multifunction display. If you wish to confirm the restart:
XPress the
abutton.
The Tire Pressure Now OK?message
appears in the multifunction display.
XPress the 9or: button to select Yes.
XPress theabutton.
The Run Flat Indicator Restartedmes-
sage appears in the multifunction display.
After a teach-in period, the tire pressure loss
warning system will monitor the set tire pres-
sures of all four tires.
If you wish to cancel the restart:
XPress the %button.
or
XWhen the TirePressureNowOK?message
appears, press the 9or: button to
select Cancel
.
XPress the abutton.
The tire pressure values stored at the last
restart will continue to be monitored.
Tire pressure monitor
General notes
If a tire pressure monitor is installed, the vehi-
cle's wheels have sensors that monitor the tire
pressures in all four tires. The tire pressure mon-
itor warns you if the pressure drops in one or
more of the tires. The tire pressure monitor only
functions if the corresponding sensors are
installed in all wheels.
Information on tire pressures is displayed in the
multifunction display. After a few minutes of
driving, the current tire pressure of each tire is
shown in the Serv.
menu of the multifunction
display, see illustration (example).
For information on the message display, refer to
the "Checking the tire pressure electronically"
section (
Ypage 355).
Tire pressure353
Wheels and tires
Z