689 Practical hints
Flat tire
Removing the wheel
1Alignment bolt
Unscrew upper-most wheel bolt and
remove.
Replace this wheel bolt with alignment
bolt1 supplied in the tool kit.
Remove the remaining bolts.
Remove the wheel.Attaching the spare wheel
1Wheel bolt for light alloy rims and
Minispare wheel with light alloy rim
2Wheel bolt for Minispare wheel with
steel rim (located in trunk with spare
wheel)
!Do not place wheel bolts in sand or dirt. This
could result in damage to the bolt and wheel hub
threads.
Warning!G
Always replace wheel bolts that are dam-
aged or rusted.
Never apply oil or grease to wheel bolts.
Damaged wheel hub threads should be re-
paired immediately. Do not continue to drive
under these circumstances! Contact an au-
thorized Mercedes-Benz Center or call
Roadside Assistance.
Incorrect wheel bolts or improperly tight-
ened wheel bolts can cause the wheel to
come off. This could cause an accident.
Make sure you are using the correct wheel
bolts.
Warning!G
Only use Genuine Mercedes-Benz wheel
bolts. Other wheel bolts may come loose.
Do not tighten the wheel bolts when the ve-
hicle is raised. Otherwise the vehicle could
fall off the jack.
691 Practical hints
Flat tire
6Wheel wrench
Tighten the five wheel bolts evenly, fol-
lowing the diagonal sequence illustrat-
ed (1 to 5), until all bolts are tight.
Observe a tightening torque of
110 lb-ft (150 Nm).
Fully collapse the jack, with handle
folded in (storage position),
(
page 669).
Store the jack and the other vehicle
tools in the designated storage space
underneath the trunk floor
(
page 668).
Warning!G
Have the tightening torque checked after
changing a wheel. The wheels could come
loose if they are not tightened to a torque of
110 lb-ft (150 Nm).
iVehicles with Advanced TPMS*:
Do not activate the tire inflation pressure moni-
tor until a full size wheel/tire with functioning
sensor has been placed back into service on the
vehicle.
692 Practical hints
Batteries
Your vehicle is equipped with two batter-
ies:
The starter battery, located in the en-
gine compartment
The battery for electrical consumers
(consumer battery), located in the
trunk
The batteries should always be sufficiently
charged in order to achieve its rated ser-
vice life. Refer to Maintenance Booklet for
battery maintenance intervals.
If you use your vehicle mostly for short-dis-
tance trips, you will need to have the bat-
tery charge checked more frequently.
When replacing the batteries, always use
batteries approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, consult an
authorized Mercedes-Benz Center about
steps you need to observe.Batteries contain materials that can harm
the environment if disposed of improperly.
Large 12-volt storage batteries contain
lead. Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.
!Do not tow-start the vehicle.
Warning!G
Observe all safety instructions and precau-
tions when handling automotive batteries.
Risk of explosion.
Fire, open flames and smoking
are prohibited when handling
batteries. Avoid creating sparks.
Battery acid is caustic. Do not
allow it to come into contact
with skin, eyes or clothing.
Wear suitable protective cloth-
ing, especially gloves, apron and
faceguard.
Wear eye protection.
Rinse any acid spills immediate-
ly with clear water. Contact a
physician if necessary.
Keep children away.
Follow the instructions in this
Operator’s Manual.
693 Practical hints
Batteries
!The consumer battery located in the trunk is
a v
alve-regulated lead acid (VRLA) battery, also
referred to as “fleece” battery. Such batteries do
not require topping-up of the electrolyte level.
VRLA batteries therefore do not have cell caps
and the battery cover is non-removable. Do not
attempt to open the consumer battery as other-
wise the battery will be damaged.
Even though VRLA batteries do not require top-
ping-up of the electrolyte level and cannot be
opened to check the electrolyte level, the bat-
tery condition must be checked periodically by
performing a battery conductance test. Refer to
Maintenance Booklet for battery condition test-
ing intervals.
As with any other battery, disconnect the con-
sumer battery if you do not intend to operate
your vehicle for an extended period of time to
prevent battery discharge or connect an acces-
sory battery charge unit expressly approved by
Mercedes-Benz for your vehicle model to main-
tain the battery charge. Contact an authorized
Mercedes-Benz Center for further information.!The factory-equipped VRLA battery is
leak-proofed. Only use a battery as replacement
that has the same security features and is of
identical size, voltage, and capacity as the facto-
ry-equipped battery.
The battery, the battery ventilation and the later-
al plug must always be securely installed when
the vehicle is in operation.
Warning!G
Failure to follow these instructions can re-
sult in severe injury or death.
Never lean over batteries while connecting,
you might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking, etc.
Warning!G
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof battery only to avoid the risk
of acid burns in the event of an accident.
Take care that you do not become statically
charged, e.g. by wearing synthetic clothing
or rubbing against textiles. For this reason,
you also should not pull or push the battery
over carpets or other synthetic materials.
Never touch the battery first. First touch the
outside body of the vehicle in order to re-
lease any possible electrostatic charges.
694 Practical hints
Batteries
Starter battery (example illustration from
S550)
1Negative terminal
2Positive terminal
Disconnecting starter battery
Secure vehicle in place with electronic
parking brake (
page 395).
Shift the automatic transmission toP
(
page 399).
Do not rub the battery with rags or cloths.
The battery could explode if touched due to
electrostatic charge or due to spark forma-
tion.
!Switch off the engine and switch off the ve-
hicle’s internal electrical functions (
page 695)
before you disconnect or remove the battery’s
terminal clamps. You could otherwise destroy
electronic assemblies such as the generator.
Have the battery checked regularly by an autho-
rized Mercedes-Benz Center. Refer to Mainte-
nance Booklet for maintenance intervals or
contact an authorized Mercedes-Benz Center for
further information.
!Do not connect any consumers directly to
the starter battery. The starter battery will other-
wise be discharged.
iOnly replace a discharged battery with a bat-
tery recommended by Mercedes-Benz. The con-
sumer battery is installed in the trunk in such a
way that it is safeguarded as much as possible
against mechanical destruction in the event of
an accident.
iRemove SmartKey from starter switch (vehi-
cles with KEYLESS-GO*: Make sure the vehicle’s
on-board electronics have status 0)
(
page 344) when you turn off the engine and
no longer require any electrical consumers. The
vehicle then uses very little power and the con-
sumer battery is spared.
iIf the consumer battery is discharged, you
must use the mechanical key to unlock the vehi-
cle (
page 671). Since the vehicle has a sepa-
rate starter battery, however, you can still start
the vehicle.
!Always disconnect the starter battery in the
order described below. You could otherwise
damage the vehicle’s electronics.
!Switch off the vehicle’s internal electrical
functions before disconnecting the starter bat-
tery. If the vehicle is stationary for more than one
hour with the SmartKey removed, you do not
need to switch off the vehicle’s internal electrical
functions.
696 Practical hints
Batteries
Starter battery
Connect the switched-off charging de-
vice to the terminals of the starter bat-
tery. Observe the operating
instructions in the manual for the
charging device while doing so.
Reinstalling starter battery
Install starter battery in engine com-
partment.
Swing retaining bar down.
Reconnecting starter battery
Make sure that the consumer battery in
the trunk is correctly installed and con-
nected.
Turn SmartKey in starter switch to po-
sition 0 and remove.
Connect the positive lead and fasten its
cover2 (
page 694).
Connect negative lead1
(
page 694).
Attach ventilation tube.
Switch on the ignition (page 344).
Start the engine (page 389).
Check vehicle functions.
!Only use charging devices with a maximum
charging voltage of 14.8 V.
Warning!G
During the charge procedure, there is a risk
of acid burns due to gases escaping from
the battery. Do not bend over the battery
during the charge procedure.
!The battery and the battery ventilation hose
must always be securely installed when the vehi-
cle is in operation.
!Always connect the starter battery in the or-
der described below. Otherwise, the vehicle’s
electronics could be damaged.
Warning!G
Do not drive without a properly installed and
connected consumer battery.
Have any work on the consumer battery car-
ried out by an authorized Mercedes-Benz
Center.
!Never invert the terminal connections.
!Make sure that the battery has a plug where
the ventilation tube is attached to it.
703 Practical hints
Towing the vehicle
Installing towing eye bolt
1Cover on right side of front bumper
1Cover on right side of rear bumperRemoving cover
Press mark on cover1 in the direction
of arrow.
Lift cover off to reveal the threaded
hole for towing eye bolt.
Installing towing eye bolt
Take towing eye bolt and wheel wrench
out of the vehicle tool kit in the trunk
(
page 668).
Screw towing eye bolt clockwise into
its stop and tighten with wheel wrench.Removing towing eye bolt
Loosen towing eye bolt counterclock-
wise with wheel wrench.
Unscrew towing eye bolt.
Store towing eye bolt and wheel
wrench in the vehicle tool kit in the
trunk.
Installing cover
Fit cover1 and snap into place.
704 Practical hints
Fuses
The electrical fuses in your vehicle serve to
switch off malfunctioning power circuits.
If a fuse is blown, the component(s) and
systems secured by that fuse will stop op-
erating.
If a newly inserted fuse blows again, have
the cause determined and rectified by an
authorized Mercedes-Benz Center.
A fuse chart explains the fuse allocation
and fuse amperages. It is located in the
trunk with the vehicle tool kit
(
page 668).
Depending on vehicle production date, the
following aids are available to help you re-
place fuses. If so equipped, they are locat-
ed in the trunk with the vehicle tool kit
(
page 668):
Spare fuses
Fuse extractorThe electrical fuses are located in different
fuse boxes:
in the dashboard on the passenger side
(
page 706)
in the dashboard on the driver’s side
(
page 706)
behind the rear center armrest
(
page 707)
on the driver’s side of the engine com-
partment (
page 705)
on the passenger side of the engine
compartment (
page 706)
Warning!G
Only use fuses approved by Mercedes-Benz
with the specified amperage for the system
in question and do not attempt to repair or
bridge a blown fuse. Using other than ap-
proved fuses or using repaired or bridged
fuses may cause an overload leading to a
fire, and/or cause damage to electrical
components and/or systems. Have the
cause determined and remedied by an
authorized Mercedes-Benz Center.
!Switch off the vehicle’s internal electrical
functions (
page 695) when you are working on
the fuses.
iA blown fuse must be replaced by an appro-
priate spare fuse (recognizable by its color or the
fuse rating given on the fuse) of the amperage
recommended in the fuse chart.
Any Mercedes-Benz Center will be glad to advise
you on this subject.iShould your vehicle not be equipped with a
fuse extractor or spare fuses please contact a
Mercedes-Benz Center or Roadside Assistance
in case of a blown fuse.