Page 398 of 462

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
Vehicles with a gasoline engine: only jump-start the vehicle when the engine and exhaust
system are cold. R
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
Bare parts of the terminal clamp do not come into contact with other metal parts while the
jumper cables are connected to the battery. 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
Turn the SmartKey to position 0 in the ignition lock and remove it ( Y
page 165). On vehicles
with KEYLESS-GO, make sure the ignition is switched off ( Y
page 165). All indicator lamps
in the instrument cluster must be off. X
Switch off all electrical consumers, e.g. rear window defroster, lighting, etc. X
Open the hood.
(Example)396
Jump-starting
Breakdown assistance
Page 428 of 462

the tire. This specifies the load-bearing capa-
city more precisely.
Curb weight
The weight of a vehicle with standard equip-
ment including the maximum capacity of fuel,
oil and coolant. It also includes the air-condi-
tioning system and optional equipment if
these are installed in the vehicle, but does not
include passengers or luggage.
Maximum load rating
The maximum load rating is the maximum
permissible weight in kilograms or lbs for
which a tire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for one
tire.
Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the maximum axle load of one axle
by two.
PSI (pounds per square inch)
A standard unit of measure for tire pressure.
Aspect ratio
Relationship between tire height and tire
width in percent.
Tire pressure
This is pressure inside the tire applying an
outward force to each square inch of the tire's
surface. The tire pressure is specified in
pounds per square inch (psi), in kilopascal
(kPa) or in bar. The tire pressure should only
be corrected when the tires are cold.
Cold tire pressure
The tires are cold: R
if the vehicle has been parked without
direct sunlight on the tires for at least three
hours and R
if the vehicle has not been driven further
than 1 mile (1.6 km) Tread
The part of the tire that comes into contact
with the road.
Bead
The tire bead ensures that the tire sits
securely on the wheel. There are several steel
wires in the bead to prevent the tire from
coming loose from the wheel rim.
Sidewall
The part of the tire between the tread and the
bead.
Weight of optional extras
The combined weight of those optional extras
that weigh more than the replaced standard
parts and more than 2.3 kg (5 lbs). These
optional extras, such as high-performance
brakes, level control, a roof rack or a high-
performance battery, are not included in the
curb weight and the weight of the accesso-
ries.
TIN (Tire Identification Number)
This is a unique identifier which can be used
by a tire manufacturer to identify tires, for
example for a product recall, and thus identify
the purchasers. The TIN is made up of the
manufacturer's identity code, tire size, tire
type code and the manufactu ring date.
L o ad bearing index
The load bearing index (also load index) is a
code that contains the maximum load bearing
capacity of a tire.
Traction
Traction is the result of friction between the
tires and the road surface.
TWR (Tongue Weight Rating)
The TWR specifies the maximum permissible
weight that the ball coupling of the trailer tow
hitch can support.426
All about wheels an d tires
Wheels and tires
Page 431 of 462

X
On light downhill gradients: place
chocks or other suitable items in front of
the wheels of the front and rear axle.
Raising the vehicle
G WARNING
If you do not position the jack correctly at the
appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate jack-
ing point of the vehicle. The base of the jack
must be positioned vertically, directly under
the jacking point of the vehicle.
! AMG vehicles with "Minispare" emer-
gency spare wheel: use the "Minispare"
emergency spare wheel only on the rear
axle . If you mount the "Minispare" emer-
gency spare wheel on the front axle, this
could result in damage to the brake system.
If a tire on the front axle is defective, an
intact wheel from the rear axle must first be
replaced with the "Minispare" emergency
spare wheel. The faulty wheel on the front
axle may only then be replaced by the
undamaged wheel from the rear axle.
Make sure to note the placard on the
"Minispare" emergency spare wheel.
! The jack is designed exclusively for jack-
ing up the vehicle at the jacking points.
Otherwise, your vehicle could be damaged. Observe the following when raising the vehi-
cle: R
To raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If used incor-
rectly, the jack could tip over with the vehi-
cle raised. R
The jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It is not suited for per-
forming maintenance work under the vehi-
cle. R
Avoid changing the wheel on uphill and
downhill slopes. R
Before raising the vehicle, secure it from
rolling away by applying the parking brake
and inserting wheel chocks. Do not disen-
gage the parking brake while the vehicle is
raised. R
The jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a
large, flat, load-bearing underlay must be
used. On a slippery surface, a non-slip
underlay must be used, e.g. rubber mats. R
Do not use wooden blocks or similar
objects as a jack underlay. Otherwise, the
jack will not be able to achieve its load-
bearing capacit y due to the restricted
height. R
Make sure that the distance between the
underside of the tires and the ground does
not exceed 1.2 in (3 cm). R
Do not place your hands or feet under the
raised vehicle. R
Do not lie under the vehicle. R
Do not start the engine when the vehicle is
raised. R
Never open or close a door or the tailgate
when the vehicle is raised. R
Make sure that no persons are present in
the vehicle when the vehicle is raised.Changing a wheel 429
Wheels and tires Z