Service A MERCEDES-BENZ CLS-Class 2012 W218 Owner's Guide
Page 285 of 356
if the coolant temperature display indicates
that the coolant is overheated.
R do not remove the pressure cap on the
coolant reservoir if the coolant temperature
is above 158  ‡ (70  †). Allow the engine to
cool down before removing the cap. The
coolant reservoir contains hot fluid and is
under pressure.
R using a rag, slowly turn the cap
approximately  1
/ 2 turn to relieve excess
pressure. If opened immediately, scalding
hot fluid and steam will be blown out under
pressure.
R do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts.XSlowly turn cap  : half a turn counter-
clockwise and allow excess pressure to
escape.XTurn cap  : further counter-clockwise and
remove it.
If the coolant is at the level of marker bar
=  in the filler neck when cold, there is
enough coolant in coolant expansion
tank  ;.
If the coolant is approximately 0.6 in
(1.5 cm) above marker bar  = in the filler
neck when warm, there is enough coolant
in coolant expansion tank  ;.XIf necessary, add coolant that has been
tested and approved by Mercedes-Benz.XReplace cap  : and turn it clockwise as far
as it will go.
For further information on coolant, see
( Y  page 350).
Windshield washer system and
headlamp cleaning system
The washer fluid reservoir is used for both the
windshield washer system and the headlamp
cleaning system.
i Vehicle components and their service
products must match. You should,
therefore, only use products that have been
tested and approved by Mercedes-Benz.
Information on tested and approved
products can be obtained at any authorized
Mercedes-Benz Center or on the Internet at
http://www.mbusa.com  (USA only).
GWARNING
Washer solvent/antifreeze is highly
flammable. Do not spill washer solvent/
antifreeze on hot engine parts, because it may
ignite and burn. You could be seriously
burned.
!  At temperatures below freezing: always
fill the washer fluid reservoir with a mix of
water and windshield washer concentrate
(e.g. MB WinterFit). There is otherwise a
risk of damaging the windshield washer
system/headlamp cleaning system.
!  Only use washer fluid concentrate which
is suitable for plastic lenses. Unsuitable
washer fluid concentrate could damage the
plastic lenses of the headlamps.
!  Do not add distilled or de-ionized water to
the washer fluid container. Otherwise, the
level sensor may be damaged.
i Add windshield washer concentrate, e.g.
MB SummerFit, to the washer fluid all year
round.
Engine compartment283Maintenance and careZ  
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Example: washer fluid reservoir
XMix the windshield washer fluid in a
container beforehand.XAt temperatures above freezing:  fill the
washer fluid reservoir with a mix of water
and windshield washer concentrate (e.g.
MB SummerFit).XAt temperatures below freezing:  fill the
washer fluid reservoir with a mix of water
and windshield washer concentrate (e.g.
MB WinterFit). Adapt the mixing ratio to the
outside temperature. For information on
the mixing ratio ( Y page 351).XTo open:  pull cap : upwards by the tab.XAdd the premixed washer fluid.XTo close:  press cap  : onto the filler neck
until it engages.
Brake fluid level
!  If you notice that the brake fluid level in
the brake fluid reservoir has fallen to the
MIN mark or less, check the brake system
immediately for leaks. Also check the
thickness of the brake linings. Contact a
qualified specialist workshop, e.g. an
authorized Mercedes-Benz Center
immediately.
Do not add brake fluid. This does not
correct the error.
Only check the brake fluid level when the
vehicle is stationary and on a level surface.
The brake fluid level is correct if it is between
MIN marking  ; and MAX marking  : on the
brake fluid reservoir.
Maintenance
Service interval display
Service messages
Information on the type of service and service
intervals (see separate Service Booklet).
You can obtain further information from an
authorized Mercedes-Benz Center or at
http://www.mbusa.com (USA only).
The service interval display informs you of the
next service due date.
If a service due date has been exceeded, you
also hear an acoustic signal.
The multifunction display shows a service
message for a few seconds, e.g.
Next service A due in .. days
Service A due
Service A overdue by ... days
The letter indicates which service is due.  A
stands for a minor service and  B for a major
service. A number or another letter may be
displayed after the letter. This figure indicates
any necessary additional maintenance work
to be performed.
You can obtain further information from an
authorized Mercedes-Benz Center.
The service interval display does not take into
account any periods of time during which the
battery is disconnected.
284MaintenanceMaintenance and care   
Page 287 of 356
Maintaining the time-dependent service
schedule:XNote down the service due date displayed
in the multifunction display before
disconnecting the battery.
or
XSubtract the battery disconnection periods
from the service date shown on the display
after reconnecting the battery.
Hiding a service message
XPress the  % or a  button on the
steering wheel.
Displaying a service message
XSwitch on the ignition.XPress  = or ;  on the steering wheel
to select the  Serv. menu.XPress 9 or :  to select the  ASSYST 
PLUS  submenu and press  a to confirm.
The service due date appears in the
multifunction display.
Please bear the following in mind
Resetting service interval display
If the qualified specialist workshop, e.g. a
Mercedes-Benz Center, carried out the
maintenance work, the service interval
display will be reset.
Further information, on maintenance for
example, can be obtained at an authorized
Mercedes-Benz Center or directly from
Mercedes-Benz.
!  If the service interval display has been
reset unintentionally, have the setting
corrected at a Mercedes-Benz Center.
Have service work carried out as described
in the Service Booklet. This may otherwise
lead to increased wear and damage to the
major assemblies or the vehicle.
Driving abroad
An extensive Mercedes-Benz Service network
is also available in other countries. You can
obtain further information from any
authorized Mercedes-Benz Center.
Care
Notes on care
Regular care of your vehicle is a condition for
retaining the quality in the long term.
Use care products and cleaning agents
recommended and approved by Mercedes-
Benz.
GWARNING
Many cleaning products can be hazardous.
Some are poisonous, others are flammable.
Always follow the instructions on the
particular container. Always open your
vehicle's doors or windows when cleaning the
inside.
Never use fluids or solvents that are not
designed for cleaning your vehicle.
Always lock away cleaning products and keep
them out of reach of children.
!  For cleaning your vehicle, do not use any
of the following:
R dry, rough or hard cloths
R abrasive cleaning agents
R solvents
R cleaning agents containing solvents
Do not scrub.
Do not touch the surfaces or protective
films with hard objects, e.g. a ring or ice
scraper. You could otherwise scratch or
damage the surfaces and protective film.
HEnvironmental note
Dispose of empty packaging and cleaning
cloths in an environmentally responsible
manner.
Care285Maintenance and careZ 
Page 293 of 356
agents containing solvents cause the surface
to become porous, and as a result, plastic
parts may break away and be thrown around
the interior when an air bag is deployed, which
may result in severe injuries.
!  Do not affix the following to plastic
surfaces:
R stickers
R films
R scented oil bottles or similar items
You can otherwise damage the plastic.
!  Do not allow cosmetics, insect repellent
or sunscreen to come into contact with the
plastic trim. This maintains the high-quality
look of the surfaces.XWipe the plastic trim with a damp, lint-free
cloth, e.g. a microfiber cloth.XHeavy soiling:  use car care and cleaning
products recommended and approved by
Mercedes-Benz.
The surface may change color temporarily.
Wait until the surface is dry again.
Cleaning the steering wheel and gear or
selector lever
XThoroughly wipe with a damp cloth or use
leather care agents that have been
recommended and approved by Mercedes-
Benz.
Cleaning genuine wood and trim
elements
XWipe the wooden trim and trim pieces with
a damp, lint-free cloth, e.g. a microfiber
cloth.XHeavy soiling:  use car care and cleaning
products recommended and approved by
Mercedes-Benz.
!  Do not use solvent-based cleaning agents
such as tar remover, wheel cleaners,
polishes or waxes. There is otherwise a risk
of damaging the surface.
!  Do not use chrome polish on trim pieces.
The trim pieces have a chrome look but are
mostly made of anodized aluminum and
can lose their shine if chrome polish is
used. Use a damp, lint-free cloth instead
when cleaning the trim pieces.
If the chrome-plated trim pieces are very
dirty, you can use a chrome polish. If you
are unsure as to whether the trim pieces
are chrome-plated or not, consult an
authorized Mercedes-Benz Center.
Cleaning the seat covers
!  Do not use microfiber cloths to clean
genuine leather, artificial leather or
Alcantara®  covers. If used often, these can
damage the cover.
!  Observe the following when cleaning:
R clean genuine leather covers carefully
with a damp cloth and then wipe the
covers down with a dry cloth. Make sure
that the leather does not become
soaked. It may otherwise become rough
and cracked. Only use leather care
agents that have been tested and
approved by Mercedes-Benz. You can
obtain these from a qualified specialist
workshop, e.g. a Mercedes-Benz Service
center.
R clean artificial leather covers with a cloth
moistened with a solution containing 1%
detergent (e.g. dish washing liquid).
R clean cloth covers with a microfiber cloth
moistened with a solution containing 1%
detergent (e.g. dish washing liquid). Rub
carefully and always wipe entire seat
sections to avoid leaving visible lines.
Leave the seat to dry afterwards.
Cleaning results depend on the type of
dirt and how long it has been there.
R clean Alcantara® covers with a damp
cloth. Make sure you wipe entire seat
sections to avoid leaving visible lines.
Care291Maintenance and careZ 
Page 304 of 356
MOExtended tires (tires with run-flat
properties)
MOExtended tires (tires with run-flat
properties) allow you to continue driving your
vehicle even if one or more tires are entirely
deflated.
MOExtended tires may only be used in
conjunction with the activated tire pressure
loss warning system or with the activated tire
pressure monitoring system.
The maximum permissible distance which
can be driven in run-flat mode depends on the
load in the vehicle. You can drive 50 miles
(80 km) if the vehicle is partially laden and
18 miles (30 km) if it is fully laden.
The maximum permissible distance which
can be driven in run-flat mode is counted from
the moment the tire pressure loss warning
appears in the multifunction display.
You must not exceed a maximum speed of
50 mph (80 km/h).GWARNING
The handling characteristics of your vehicle
deteriorate in run-flat mode, for example:
R when cornering
R when braking
R when accelerating rapidly
Adapt your driving style accordingly and avoid
sudden changes in direction and sudden
acceleration, as well as driving over obstacles
(i.e. curbs, potholes), and driving off-road.
This is particularly the case when the vehicle
is heavily laden.
The maximum permissible distance that can
be driven in run-flat mode depends to a large
extent on the loads placed on the vehicle. It
can be shorter due to high speeds, a heavy
load, sudden changes in direction, the road
surface condition, outside temperature, etc.,
or further if you drive carefully and
conservatively.
Do not continue to drive in run-flat mode if:
R you hear banging noises.
R the vehicle starts to shake.
R you see smoke and smell rubber.
R ESP ®
 is intervening constantly.
R there are tears in the sidewalls of the tire.
After driving in run-flat mode, you must have
the wheel(s) checked for damage at a
qualified specialist workshop which has the
necessary specialist knowledge and tools to
carry out the work required. The defective tire
must be replaced in every case.
Mercedes-Benz recommends that you use an
authorized Mercedes-Benz Center for this
purpose. In particular, work relevant to safety
or on safety-related systems must be carried
out at a qualified specialist workshop.
i When replacing one or all tires, make sure
that you only use tires marked
MOExtended and of the specified size for
the vehicle.
Battery
Important safety notes
In order for the battery to achieve the
maximum possible service life, it must always
be sufficiently charged.
!  Have the battery checked regularly at a
qualified specialist workshop, such as an
authorized Mercedes-Benz Center.
Adhere to the service intervals indicated in
the service booklet or ask a qualified
specialist workshop, such as an authorized
Mercedes-Benz Center.
Have the battery charge checked more
frequently if you use the vehicle mainly for
short trips or if you leave it standing idle for
a lengthy period.
Only replace a battery with a battery that has
been recommended by Mercedes-Benz.
302BatteryBreakdown assistance 
Page 311 of 356
XRelease the parking brake.XLeave the SmartKey in position 2 in the
ignition lock.
Transporting the vehicle
The towing eye can be used to pull the vehicle
onto a trailer or transporter for transporting
purposes.
XTurn the SmartKey to position  2 in the
ignition lock.XShift the automatic transmission to
position  N.
As soon as the vehicle is loaded:
XPrevent the vehicle from rolling away by
applying the parking brake.XShift the automatic transmission to
position  P.XTurn the SmartKey to position  0 in the
ignition lock and remove the SmartKey
from the ignition lock.XSecure the vehicle.
!  Only lash the vehicle down by the wheels
or wheel rims, not by parts of the vehicle
such as axle or steering components.
Otherwise, the vehicle could be damaged.
Notes for 4MATIC vehicles
!  Vehicles with 4MATIC must not be towed
with either the front or the rear axle raised,
as doing so will damage the transmission.
If the vehicle has transmission damage or
damage to the front or rear axle, have it
transported on a transporter or trailer.
In the event of damage to the electrical 
system
If the battery is defective, the automatic
transmission will be locked in position  P. To
shift the automatic transmission to position
N , you must provide power to the vehicle's
electrical system in the same way as when
jump-starting ( Y page 305).
Have the vehicle transported on a transporter
or trailer.
Tow-starting (emergency engine
starting)
!  Vehicles with automatic transmission
must not be started by tow-starting. This
could otherwise damage the transmission.
Fuses
Important safety notes
The fuses in your vehicle serve to close down
faulty circuits. If a fuse blows, all the
components on the circuit and their functions
stop operating.
GWARNING
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
approved 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.
Blown fuses must be replaced with fuses of
the same rating, which you can recognize by
the color and value. The fuse ratings are listed
in the fuse allocation chart. An authorized
Mercedes-Benz Center will be happy to
advise you.
i If a fuse has blown, contact a breakdown
service or an authorized Mercedes-Benz
Center.
If the newly inserted fuse also blows, have the
cause traced and rectified at a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center.
!  Only use fuses that have been approved
for Mercedes-Benz vehicles and which
Fuses309Breakdown assistanceZ 
Page 318 of 356
(100 km) as they only reach their full
performance after this distance.
R Do not use tires that are excessively worn
as the tire traction on wet road surfaces
decreases significantly when the tread
depth is less than  1
/ 8 inch (3 mm).
R Replace the tires after six years at the
latest, regardless of wear. This also applies
to the emergency spare wheel/spare
wheel.
The service life of tires depends on the
following factors amongst other things:
R driving style
R tire pressure
R mileage
MOExtended tires (tires with run-flat
properties)
MOExtended tires (tires with run-flat
properties) allow you to continue driving your
vehicle even if one or more tires are entirely
deflated.
MOExtended tires may be used only in
conjunction with the activated tire pressure
loss warning system or the activated tire
pressure monitoring system and only on
wheels specifically tested by Mercedes-Benz.
You will find notes on driving with a flat tire in
the "Breakdown assistance" section
( Y  page 302).
Winter operation
Please bear the following in mind
At the onset of winter, have your vehicle
winterproofed at a qualified specialist
workshop, e.g. at an authorized Mercedes-
Benz Center.
Observe the notes in the "Changing a wheel"
section ( Y page 338).
Driving with summer tires
At temperatures below 45 ‡ (+7 †), the
elasticity of summer tires and therefore also
traction and braking capability are reduced
considerably — equip your vehicle with
M+S tires. Using summer tires at very cold
temperatures could cause tears to form,
thereby damaging the tires permanently.
Mercedes-Benz cannot accept responsibility
for this type of damage.
M+S tires
At temperatures below 45 ‡(+7 †), use
winter tires or all-season tires. Both types of
tire are identified by the M+S marking.
Only winter tires bearing the  i snowflake
symbol in addition to the M+S marking
provide the best possible grip in wintry road
conditions. Only these tires will allow driving
safety systems such as ABS and ESP ®
 to
function optimally in winter, as these tires
have been designed specifically for driving on
snow.
Use M+S tires of the same make and tread on
all wheels to maintain safe handling
characteristics.
GWARNING
M+S tires with a tread depth of less than  1
/ 6
inch (4 mm) must be replaced immediately.
They are no longer suitable for use in winter.
Always observe the maximum permissible
speed specified for the M+S tires you have
mounted.
Once you have mounted the winter tires:
XCheck the tire pressures ( Y page 321).XRestart the tire pressure monitor
( Y  page 322).GWARNING
If you use your spare wheel when M+S tires
are mounted on the other wheels, be aware
that the difference in tire characteristics
316Winter operationWheels and tires 
Page 332 of 356
iThe actual values for tires are specific to
each vehicle and may deviate from the
values in the illustration.
Maximum tire load  : is the maximum
permitted weight for which the tire is
approved.
Further information on tire loads
( Y  page 331).
Uniform Tire Quality Grading
Standards
Overview of Tire Quality Grading
Standards
The Uniform Tire Quality Grading is a U.S.
Government requirement. Their purpose is to
provide drivers with consistent and reliable
information regarding tire performance. Tire
manufacturers are required to grade tires
using three performance factors: tread
wear  :, tire traction  ;, and temperature
resistance  =. Although not a Government of
Canada requirement, all tires made for sale in
North America have these grades branded on
the sidewall.
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
Where applicable, the tire grading
information can be found on the tire sidewall
between the tread shoulder and maximum
tire width.
For example:Tread wearTractionTemperature200AAA
All passenger car tires must conform to the
statutory safety requirements in addition to
these grades.
Tread wear
The tread wear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified
U.S. government course. For example, a tire
graded 150 would wear one and one-half
times as well on the government course as a
tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm, due to variations in driving habits,
service practices and differences in road
characteristics and climate conditions.
Traction
GWARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
The traction grades, from highest to lowest,
are AA, A, B, and C. Those grades represent
330Uniform Tire Quality Grading StandardsWheels and tires   
Page 335 of 356
Example:
The load bearing index 91 is equivalent to a
maximum load of 1356 lbs (615 kg) that the
tire can carry. For further information on the
maximum tire load in kilograms and pounds,
see ( Y page 329).
For further information on the load bearing
index, see Load index ( Y page 334).
Speed index:  speed index B specifies the
approved maximum speed of the tire.GWARNING
Even when permitted by law, never operate a
vehicle at speeds greater than the maximum
speed rating of the tires.
Exceeding the maximum speed for which tires
are rated can lead to sudden tire failure,
causing loss of vehicle control and possibly
resulting in an accident and/or serious
personal injury and possible death, for you
and for others.
Regardless of the speed index always observe
the speed limits. Drive carefully and adapt
your driving style to the traffic conditions.
Summer tiresIndexSpeed ratingQUp to 100 mph (160 km/h)RUp to 106 mph (170 km/h)SUp to 112 mph (180 km/h)TUp to 118 mph (190 km/h)HUp to 130 mph (210 km/h)VUp to 149 mph (240 km/h)WUp to 168 mph (270 km/h)YUp to 186 mph (300 km/h)ZR...YUp to 186 mph (300 km/h)ZR...(..Y)above 186 mph (300 km/h)ZRabove 149 mph (240 km/h)R Optionally, tires with a maximum speed of
over 149 mph (240 km/h) may have "ZR"
in the size description depending on the
manufacturer (e.g. 245/40 ZR 18).
The service specifications consist of load
bearing index  A and speed index  B.
R If the size description of your tire includes
"ZR" and there are no service
specifications, ask the tire manufacturer in
order to find out the maximum speed.
If a service specification is available, the
maximum speed is limited according to the
speed index in the service specification.
Example: 245/40 ZR 18 97 Y. In this
example, "97 Y" is the service specification.
The letter "Y" represents the speed index
and the maximum speed of the tire is
limited to 186 mph (300 km/h).
R Every tire that has a maximum speed above
186 mph  (300 km/h) must have "ZR" in the
size description  and the service
specification must be given in brackets.
Example: 275/40 ZR 18 (99 Y). The speed
index "(Y)" shows that the maximum speed
of the tire is above 186 mph (300 km/h).
Ask the tire manufacturer to find out the
maximum speed.All-weather tires and winter tiresIndexSpeed ratingQ M+S 25Up to 100 mph (160 km/h)T M+S25Up to 118 mph (190 km/h)H M+S 25Up to 130 mph (210 km/h)V M+S25Up to 149 mph (240 km/h)
i
Not all tires that have the M+S
identification offer the driving
characteristics of winter tires. Winter tires
have, in addition to the  M+S identification,
the  i  snow flake symbol on the tire
sidewall. Tires with this identification fulfill
the requirements of the Rubber
25 or M+S i for winter tires.Tire labeling333Wheels and tiresZ 
Page 345 of 356
Useful information ............................344
Genuine Mercedes-Benz parts  .........344
Warranty  ............................................ 344
Identification plates  .........................345
Service products and capacities  .....346
Vehicle data  ...................................... 351343Technical data