check engine light MERCEDES-BENZ S-Class 2012 W221 Owner's Manual

Climate controlAutomatic climate control .............291
COMAND ....................................... 265
Controlling automatically ...............293
Controlling centrally (COMAND) ....267
Cooling with air dehumidification ..293
Cooling with air dehumidification
(COMAND) ..................................... 267
Defrosting the windows .................296
Defrosting the windshield ..............296
Important safety notes ..................290
Indicator lamp ................................ 293
Main menu ..................................... 266
Maximum cooling .......................... 296
Overview of systems ......................290
Problems with cooling with air
dehumidification ............................ 293
Problem with the rear window
defroster ........................................ 297
Rear compartment (COMAND) ......268
Rear control panel .........................291
Refrigerant ..................................... 528
Setting the air distribution .............295
Setting the airflow .........................295
Setting the airflow (COMAND) .......268
Setting the air vents ......................298
Setting the footwell temperature
(COMAND) ..................................... 268
Setting the temperature ................294
Switching air-recirculation mode
on/off ............................................ 297
Switching on/off ........................... 292
Switching residual heat on/off ......298
Switching the rear window
heating on/off ............................... 297
Coat hooks ......................................... 434
Cockpit Overview .......................................... 34
see Instrument cluster
Color, setting (TV, video) .................. 240
COMAND At a glance (overview) .................... 118
Back button ................................... 119
Basic functions .............................. 133
Components .................................. 118
Display ........................................... 121
Example of operation .....................128
Function buttons ........................... 119Menu overview .............................. 121
Remote control .............................. 125
Switching on/off ........................... 133
System settings ............................. 143
COMAND controller ........................... 118
COMAND display Cleaning instructions .....................125
Folding in and swiveling .................124
Setting ........................................... 143
COMAND operating system .............. 118
Combination switch .......................... 279
Compass function ............................. 188
Conference connection ..................... 201
Consumption statistics (on-board
computer) .......................................... 376
Contrast, setting (TV, video) ............ 240
Convenience closing feature .............. 94
Convenience opening feature ............ 93
Convenience telephone Importing contacts ........................204
Convenience telephony .................... 193
Introduction ................................... 193
Coolant (engine)
Checking the level .........................460
Display message ............................ 404
Notes ............................................. 529
Temperature (on-board computer) . 379
Temperature gauge ........................ 372
Cooling
see Climate control
Copy protection (CD/DVD) ............... 229
Cornering light function Display message ............................ 401
Function/notes ............................. 280
Cruise control
Cruise control lever .......................331
Deactivating ................................... 332
Display message ............................ 415
Driving system ............................... 330
Function/notes ............................. 330
Important safety notes ..................330
LIM indicator lamp .........................331
Setting a speed .............................. 332
Storing and maintaining current
speed ............................................. 3318Index

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops ( Y page 31).
Occupant safety
Overview of occupant safety
In this section, you will learn the most
important facts about the restraint system
components of the vehicle.
The restraint system consists of:
R seat belts
R child restraint systems
R LATCH-type (ISOFIX) child seat anchors
Additional protection is provided by:
R SRS (Supplemental Restraint System)
R NECK-PRO head restraints/NECK-PRO
luxury head restraints
R PRE-SAFE ®
R Air bag system components with:
- PASSENGER AIR BAG OFF indicator lamp
- front-passenger seat with Occupant
Classification System (OCS)
The different air bag systems work
independently of each other. The protective
functions of the system work in conjunction
with each other. Not all air bags are deployed
in an accident.
GWARNING
Modifications to or work improperly
conducted on restraint system components
or their wiring, as well as tampering with
interconnected electronic systems, can lead
to the restraint systems no longer functioning
as intended.
Air bags or Emergency Tensioning Devices
(ETDs), for example, could deploy
inadvertently or fail to deploy in accidents
although the deceleration threshold for air
bag deployment is exceeded. Therefore,
never modify the restraint systems. Do not
tamper with electronic components or their
software.
i See "Children in the vehicle"
( Y page 62) for more information on
infants and children traveling with you in
the vehicle and restraints for infants and
children.
SRS (Supplemental Restraint System)
Introduction
SRS consists of:
R the 6 SRS warning lamp
R air bags
R air bag control unit (with crash sensors)
R Emergency Tensioning Devices
R belt force limiters
SRS reduces the risk of occupants coming
into contact with the vehicle's interior in the
event of an accident. It can also reduce the
effect of the forces to which occupants are
subjected during an accident.
SRS warning lamp
SRS functions are checked regularly when
you switch on the ignition and when the
engine is running. Therefore, malfunctions
can be detected in good time.
The 6 SRS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out no later than a few seconds
after the engine is started.
44Occupant safetySafety

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops ( Y page 31).
SmartKey
Important safety notes
GWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts.GWARNING
If a key ring is too heavy or too large, the
weight acting on the key could cause it to turn
in the ignition lock or catch on the steering
wheel. This could cause the engine to be
switched off suddenly. You could lose control
of the vehicle and cause an accident. Do not
attach any heavy or large key rings to the key
that is inserted in the ignition.
General notes
If you cannot lock or unlock the vehicle with
the SmartKey, either the battery in the
SmartKey is discharged, the SmartKey is
faulty or the starter battery is discharged.
XCheck the battery in the SmartKey and
replace it if necessary ( Y page 82).XUnlock the driver's door using the
mechanical key ( Y page 87).XLock the vehicle ( Y page 88).XHave the starter battery and the battery
contacts checked at a qualified specialist
workshop.
If the SmartKey is faulty, contact Roadside
Assistance or a qualified specialist workshop.
SmartKey functions
General notes
i USA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful
interference, and
2. this device must accept any interference
received, including interference that may
cause undesired operation.
78SmartKeyOpening/closing

ProblemPossible causes/consequences and M SolutionsYou have lost the
mechanical key.XReport the loss immediately to the vehicle insurers.XIf necessary, have the locks changed as well.The engine cannot be
started using the
SmartKey.The on-board voltage is too low.XRemove the SmartKey and reinsert it into the ignition lock.XStart the engine within 30 seconds of inserting the SmartKey in
the ignition lock.XRepeat if necessary.
If the engine does not start after several attempts:
XCheck the starter battery and charge it if necessary
( Y page 478).
or
XJump-start the vehicle ( Y page 481).
or
XConsult a qualified specialist workshop.The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle.A door is open. Therefore, the SmartKey cannot be detected as
easily.XClose the door and try to start the vehicle again.There is interference from a powerful source of radio waves.XStart your vehicle with the SmartKey in the ignition lock.Doors
Important safety notes
GWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts.Doors85Opening/closingZ

You can install new map software yourself
which, depending on the scope, may consist
of one or more DVDs.
The installation process can take between
10 and 120 minutes, depending on the scope
of the map software. If the radio is switched
on before you start the installation process,
you can still adjust the volume. You can also
use COMAND to operate automatic climate
control and to cancel the process. Other
functions are not operational. If possible,
carry out the installation when the vehicle is
stationary. The DVD read speed is higher
when the vehicle is stationary than when it is
in motion, so less time is required. If the
starter battery is not sufficiently charged,
COMAND may end the process automatically
in order to protect the battery. Therefore, let
the engine idle during the installation
process.GWARNING
Never leave the engine running in enclosed
spaces. The exhaust gases contain toxic
carbon monoxide. Breathing in exhaust fumes
is a health hazard and can lead to
unconsciousness or death.
Displaying information on the map
version currently in use
XTo activate navigation mode: press the
S function button once or twice.XTo show the menu: press W the COMAND
controller.XSelect Navi in the main function bar by
sliding VÆ and turning cVd the COMAND
controller and press W to confirm.XSelect Map Version and press W to
confirm.
Notes on handling DVDs
R Only hold DVDs by the edge.
R Handle DVDs carefully to prevent reading
errors.
R Avoid getting scratches, fingerprints and
dust on DVDs.
R Use a commercially-available cleaning
cloth to clean discs. When cleaning CDs,
you should wipe in straight lines from the
center outwards rather than in a circular
motion.
R Place DVDs back in their cases after use.
R Protect DVDs from heat and direct sunlight.
Map software copy protection
Map software for COMAND is subject to a
charge. The map software has just one
activation code which is usable in one vehicle
only, and is not transferable. You can obtain
the six-digit activation code from your
authorized Mercedes-Benz Center. If you
have lost the activation code, or if COMAND
does not accept the activation code that you
have received, contact your authorized
Mercedes-Benz Center.
Your vehicle is supplied with map software at
the factory. Depending on the country, map
software for your region is either pre-installed
(Europe/USA) or the map software is
supplied as a DVD (all other countries). You
do not require an activation code for the map
software that is provided with your vehicle.
If the map software on your vehicle has been
installed at the factory and you wish to
reinstall it, this also does not necessitate
entry of the activation code.
Installation processXLoad the map software DVD in the DVD
drive ( Y page 220).
COMAND checks the DVD and shows a
corresponding message in the display.
Map software is not compatible with the
navigation system
You will see a message that the map software
cannot be installed.
XTo confirm the message: press W.
COMAND ejects the DVD.XTake the DVD out of the slot.XInsert a DVD which is compatible with the
vehicle’s navigation system.Navigation189COMANDZ

Rear-compartment overhead control panel
:Reading lamp;Press p consecutively:to switch the reading lamp and interior
lighting onto switch only the reading lamp onto switch the reading lamp off=Interior lighting
Interior lighting control
Important notes
In order to prevent the vehicle's battery from
discharging, the interior lighting functions are
automatically deactivated after some time
except for when the SmartKey is in position
2 in the ignition lock.
Automatic interior lighting control
XTo switch on/off: press the | button.
The OFF indicator lamp shows whether the
automatic interior lighting control is
deactivated (indicator lamp on) or
activated (indicator lamp off).
The interior lighting automatically switches
on if you:
R unlock the vehicle
R open a door
R remove the SmartKey from the ignition lock
The interior light is activated for a short while
when the SmartKey is removed from the
ignition lock. You can activate this delayed
switch-off using COMAND ( Y page 263).
Manual interior lighting controlXTo switch the front interior lighting on/
off: press the c button.XTo switch the rear interior lighting on/
off: press the u button.XTo switch the reading lamps on/off:
press the p button.
Replacing bulbs
Important safety notes
Xenon bulbs
If your vehicle is equipped with Xenon bulbs,
you can recognize this by the following: the
cone of light from the Xenon bulbs moves
from the top to the bottom and back again
when you start the engine. For this to be
observed, the lights must be switched on
before starting the engine.
GDANGER
Xenon bulbs carry a high voltage. You could
get an electric shock and be seriously or even
fatally injured if you touch the electric
contacts on Xenon bulbs. Therefore, never
remove the cover from Xenon bulbs.
Do not change Xenon bulbs yourself, but have
them replaced at a qualified specialist
workshop which has the necessary specialist
knowledge and tools to carry out the work
required.
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.
Bulbs and lamps are an important aspect of
vehicle safety. You must therefore make sure
that these function correctly at all times.
Have the headlamp setting checked regularly.
282Replacing bulbsLights and windshield wipers

ProblemPossible causes/consequences and M SolutionsVehicles with a
gasoline engine:
The engine is not
running smoothly and
is misfiring.There is a malfunction in the engine electronics or a mechanical
component of the engine management system.XOnly depress the accelerator pedal slightly.XHave the cause rectified immediately at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz Center.
Otherwise, non-combusted fuel may get into the catalytic
converter and damage it.The coolant
temperature gauge
shows a value above
248 ‡ (120 †).The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.XStop as soon as possible and allow the engine and the coolant
to cool down.XCheck the coolant level ( Y page 460). Observe the warning
notes as you do so and add coolant if necessary.Automatic transmission
Important safety notes
GWARNING
It is dangerous to shift the automatic
transmission out of parking position P or
neutral position N if the engine speed is
higher than idle speed. If your foot is not firmly
on the brake pedal, the vehicle could
accelerate quickly forward or in reverse. You
could lose control of the vehicle and hit
someone or something. Only shift into gear
when the engine is idling normally and when
your right foot is firmly on the brake pedal.
GWARNING
Keep in mind that turning off the engine alone
only will shift the automatic transmission into
neutral position N automatically.
Always shift the automatic transmission into
park position P before turning off the engine.
Otherwise the vehicle could roll away which
could result in an accident and/or serious
personal injury.
GWARNING
HYBRID vehicles: It is imperative that you read
the HYBRID Supplemental Operating
Instructions included in your vehicle literature
portfolio. You may otherwise not receive all
necessary safety information and warning for
the operation of your vehicle.
DIRECT SELECT lever
Overview of transmission positions
The DIRECT SELECT lever is on the right of the
steering column.
PPark position with parking lockRReverse gear310Automatic transmissionDriving and parking

Low outside temperatures
! Do not use gasoline to refuel vehicles with
a diesel engine. Never mix diesel with
gasoline or kerosene, as this may result in
damage to the engine or fuel system.
Diesel fuel with improved cold flow properties
is available during the winter months. Further
information on fuel properties can be
obtained from oil companies, e.g. at gas
stations.
Refueling
Fuel filler flap
The fuel filler flap is unlocked or locked
automatically when you open or close the
vehicle with the SmartKey or using KEYLESS-
GO.
The position of the fuel filler cap is displayed
in the instrument cluster 8. The arrow
next to the filling pump indicates the side of
the vehicle.
:To open the fuel filler flap;To insert the fuel filler cap=Tire pressure table?Fuel type
Opening
XSwitch off the engine.XRemove the SmartKey from the ignition
lock.KEYLESS-GO: open the driver’s door. This
switches the ignition to position 0, which
corresponds to having removed the
SmartKey. The driver’s door can be closed
again.XPress the fuel filler flap in the direction of
arrow :.
The fuel filler flap opens slightly.XOpen the fuel filler flap.XTurn the fuel filler cap counter-clockwise
and remove it.XInsert the fuel filler cap into the holder
bracket on the inside of filler flap ;.XCompletely insert the pump nozzle into the
filler neck and refuel.XOnly fill the tank until the pump nozzle
switches off.
! Overfilling the fuel tank could damage the
fuel system.
Closing
XReplace the fuel filler cap and turn it
clockwise. The fuel filler cap audibly
engages.XClose the fuel filler flap.
i If you drive with the fuel filler cap open,
the reserve fuel warning lamp flashes. In
addition, the ; Check Engine warning
lamp may light up. A message appears in
the multifunction display ( Y page 407).
For further information on warning and
indicator lamps in the instrument cluster,
see ( Y page 427).
i Close the fuel filler flap before locking the
vehicle. A locking pin otherwise prevents
the fuel filler flap from closing after the
vehicle has been locked.
Refueling319Driving and parkingZ

Steering and braking requires significantly
more effort and you could lose control of the
vehicle and cause an accident as a result.
Do not turn off the engine while the vehicle is
in motion.
Exhaust checkGWARNING
Inhalation of exhaust gas is hazardous to your
health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause
unconsciousness and possible death.
Do not run the engine in confined areas (such
as a garage) which are not properly ventilated.
If you think that exhaust gas fumes are
entering the vehicle while driving, have the
cause determined and corrected
immediately. If you must drive under these
conditions, drive only with at least one
window fully open at all times.
Certain engine systems are designed to keep
the level of poisonous components in exhaust
fumes within legal limits.
These systems only work at peak efficiency
when they are maintained exactly in
accordance with the manufacturer's
specifications. For this reason, all work on the
engine must be carried out only by qualified
and authorized Mercedes-Benz technicians.
The engine settings must not be changed in
any circumstances. Furthermore, all specific
service work must be carried out at regular
intervals and in accordance with the
Mercedes-Benz service requirements. Details
can be found in the Service Booklet.
Brakes
Important safety notes
GWARNING
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result in drive wheel slip and reduced vehicle
control. Your vehicle's ABS will not prevent
this type of loss of control.GWARNING
Make sure that you do not endanger other
road users when you apply the brakes.
Downhill gradients
! On long and steep gradients, you must
reduce the load on the brakes by shifting
early to a lower gear. This allows you to take
advantage of the engine braking effect and
helps avoid overheating and excessive
wear of the brakes.
When you take advantage of the engine
braking effect, a drive wheel may not turn
for some time, e.g. on a slippery road
surface. This could cause damage to the
drive train. This type of damage is not
covered by the Mercedes-Benz warranty.
Heavy and light loads
GWARNING
Depressing the brake pedal constantly results
in excessive and premature wear to the brake
pads.
It may also cause the brakes to overheat,
seriously impairing their effectiveness. It may
then not be possible to stop the vehicle in
sufficient time to avoid an accident.
If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately, but
drive on for a short while. This allows the
airflow to cool the brakes more quickly.
Wet roads
GWARNING
After driving in heavy rain for some time
without applying the brakes or through water
deep enough to wet brake components, the
first braking action may be somewhat
reduced. You have to depress the brake pedal
Driving tips327Driving and parkingZ

more firmly. Maintain a safe distance from
vehicles in front.
After driving on a wet road or having the
vehicle washed, brake firmly while paying
attention to the traffic conditions. This will
warm up the brake discs, thereby drying them
more quickly and protecting them against
corrosion.
Limited braking performance on salt
treated roadsGWARNING
The layer of salt on the brake discs and the
brake pads/linings may cause a delay in the
braking effect, resulting in a significantly
longer braking distance, which could lead to
an accident.
To avoid this danger, you should:
R occasionally brake carefully, without
putting other road users at risk, when you
are driving on salted roads. This helps to
remove any salt that may have started to
build up on the brake discs and the brake
pads/linings.
R maintain a greater distance to the vehicle
ahead and drive with particular care.
R carefully apply the brakes at the end of a
trip and immediately after commencing a
new trip, so that salt residues are removed
from the brake discs.
Servicing the brakes
! If the red brake warning lamp lights up in
the instrument cluster and you hear a
warning tone while the engine is running,
the brake fluid level may be too low.
Observe additional warning messages in
the multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked
immediately. This work should be carried
out at an authorized Mercedes-Benz
Center.
All checks and maintenance work on the
brake system must be carried out at a
qualified specialist workshop. This work
should be carried out at an authorized
Mercedes-Benz Center.
Have the brake pads replaced and the brake
fluid renewed at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz
Center.GWARNING
If brake pads or brake fluid other than those
recommended are used, the braking
properties of the vehicle can be degraded to
an extent that safe braking is substantially
impaired. This could result in an accident.
! Vehicles with 4MATIC: function or
performance tests may only be carried out
on a 2-axle dynamometer. If you are
planning to have the vehicle tested on such
a dynamometer, contact an authorized
Mercedes-Benz Center to obtain further
information first. Otherwise, you could
damage the drive train or the brake system.
! Vehicles with 4MATIC: as the ESP®
system operates automatically, the engine
and the ignition must be switched off
(SmartKey in position 0 or 1 in the ignition
lock or Start/Stop button in position 0 or
1 ) when the electric parking brake is being
tested on a brake dynamometer.
Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system.
! Vehicles with 4MATIC: as the ESP®
system operates automatically, the engine
and the ignition system must be switched
off (SmartKey in position 0 or 1 in the
ignition lock or Start/Stop button in
position 0 or 1) when:
R testing the electric parking brake on a
brake dynamometer.
R you intend to have the vehicle towed with
one of the axles raised.
328Driving tipsDriving and parking