2012 MERCEDES-BENZ CLS-Class start stop button

:ECO symbol;ECO start/stop display message
The ECO start/stop function is activated each
time the engine is switched on. If all the
requirements are fulfilled for automatic
engine switch-off ( Y page 136), green ECO
symbol : is shown in the multifunction
display and Stop/Start active ; appears.
If all the requirements are not fulfilled, ECO
symbol : is shown in yellow and Stop/
Start inactive ; appears.
If the ECO start/stop function is deactivated
( Y page 137), ECO symbol : is not shown.
GWARNING
If the engine is switched off and the ECO
symbol is shown in green in the multifunction
display, the engine has been switched off
automatically. All of the vehicle's systems
remain active. If you open the door, unfasten
your seat belt or remove your foot from the
brake pedal, the engine will automatically
start. The vehicle may begin moving. You
could suffer serious or even fatal injury or
cause an accident resulting in injury or death.
Never leave the vehicle while the ECO symbol
in the multifunction display is shown in green
or yellow. Always secure the vehicle against
rolling away before leaving it.
! Always switch the ignition off and take the
key with you when leaving the vehicle.
Automatic engine switch-off
The ECO start/stop function switches the
engine off automatically if the vehicle is
braked to a standstill and the brake remains
depressed with the transmission in position
D or N.
i
You can still activate the HOLD function
when the vehicle is stationary, even if the
engine has been switched off
automatically. It is then not necessary to
continue applying the brakes during the
automatic stop phase. When you depress
the accelerator pedal, the engine starts
automatically and the braking effect of the
HOLD function is deactivated. Depress the
accelerator pedal carefully, as the engine
must be started first.
The engine is only switched off if:
R the outside temperature is within the range
which is suitable for the system.
R the engine is at normal operating
temperature.
R the set temperature for the vehicle interior
has been reached.
R the battery is sufficiently charged.
R the system detects that the windshield is
not fogged up when the air-conditioning
system is switched on.
R the hood is closed.
R no engine relevant diagnostics are active.
R the front door is closed and the seat belt is
fastened.
Automatic engine start
The engine is started automatically if you:
R release the brake pedal when HOLD is not
activated and the transmission is in
position D or N
R shift the transmission to position R
R depress the accelerator pedal
R switch off the ECO start/stop function by
pressing the ECO button
R switch to drive program S, S+ or M
R unfasten your seat belt or open the driver's
door
The engine is also started automatically if:
R the vehicle starts to roll.
R the brake system requires this.
136DrivingDriving and parking

Rthe system detects moisture on the
windshield when the air-conditioning
system is switched on.
R the temperature in the vehicle interior
deviates from the set range.
R the charge level of the battery is too low.
Deactivating/activating the ECO start/
stop function
Example: ECO button
Deactivating
XPress button :.
or
XSwitch to drive program S, S+ or
M (Y page 143).
Indicator lamp ; on button :, the ECO
symbol and the Stop/Start active or
Stop/Start inactive message go out in
the multifunction display.
Activating
XPress button :.
or
XSwitch to drive program C(Y page 143).
Indicator lamp ; lights up. If all conditions
for automatic engine switch-off
( Y page 136) are fulfilled, the ECO symbol
is shown in green in the multifunction
display. In addition, the Stop/Start
active message appears in the
multifunction display. If not all conditions
have been fulfilled for automatic engine
switch-off ( Y page 136), the Stop/Start
inactive message is shown in themultifunction display and the ECO symbol
is shown in yellow.
i If you press button : while drive program
S , S+ or M is active, the automatic
transmission shifts to drive program C.
i If indicator lamp ; is off, the ECO start/
stop function has been deactivated
manually or as the result of a malfunction.
The engine will then not be switched off
automatically when the vehicle stops.
i Every time you start the engine, the ECO
start/stop function is switched on and the
automatic transmission shifts to automatic
drive program C.
Driving137Driving and parkingZ

Problems with the engineProblemPossible causes/consequences and M SolutionsThe engine does not
start. The starter motor
can be heard.R There is a malfunction in the engine electronics.
R There is a malfunction in the fuel supply.XBefore attempting to start the engine again, turn the SmartKey
in the ignition back to position 0 or press the Start/Stop button
repeatedly until all indicator lamps in the instrument cluster go
out.XTry to start the engine again ( Y page 134). Avoid excessively
long and frequent attempts to start the engine as these will drain
the battery.
If the engine does not start after several attempts:
XConsult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center.The engine does not
start. You cannot hear
the starter motor.The on-board voltage is too low because the battery is too weak
or discharged.XJump-start the vehicle ( Y page 305).
If the engine does not start despite attempts to jump-start it:
XConsult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center.The starter motor was exposed to a thermal load that was too high.XAllow the starter motor to cool down for approximately two
minutes.XTry to start the engine again.
If the engine still does not start:
XConsult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center.138DrivingDriving and parking

automatic transmission directly from D to
R , from R to D or directly to P. The
automatic transmission could otherwise be
damaged.
HOLD function or DISTRONIC PLUS: the
automatic transmission automatically
switches to transmission position P if the
vehicle is braked by the HOLD function or
DISTRONIC PLUS. In addition, at least one of
the following conditions must be fulfilled:
R the engine is switched off.
R the driver's door is open and the seat belt
is not in the buckle.
Engaging parking position P in AMG
vehiclesXIf the vehicle is stationary, press P
button :.
Engaging reverse gear R
!
Only shift the automatic transmission to
R when the vehicle is stationary.
XWhen the vehicle is stationary, depress the
brake pedal.XPush the DIRECT SELECT lever up past the
first point of resistance.
Neutral N with ECO start/stop function
activated
The ECO start/stop function switches the
engine off automatically if the vehicle is
braked to a standstill when in neutral N and
the brake is still depressed.
For further information on the ECO start/stop
function ( Y page 135).
Shifting to neutral NXWhen the vehicle is stationary, depress the
brake pedal.XPush the DIRECT SELECT lever up or down
to the first point of resistance.
If the engine has been switched off, the
automatic transmission automatically
switches to N.
Remaining in neutral N
If the automatic transmission is to remain in
neutral N, e.g. for washing the vehicle in car
washes with a towing device, please observe
the following instructions:
GWARNING
When leaving the SmartKey in the starter
switch, do not leave children unattended in
the vehicle. It is possible for children to switch
on the ignition which could result in
unsupervised use of vehicle equipment.
Unsupervised use of vehicle equipment could
result in an accident and/or serious personal
injury.
Using the SmartKey:
R make sure that the ignition is switched on.
R when the vehicle is stationary, depress the
brake pedal and keep it depressed.
R shift to neutral N.
R release the brake pedal.
R if applied, release the parking brake.
R switch off the ignition and leave the
SmartKey in the ignition lock.
Using KEYLESS-GO:
R make sure that the ignition is switched on.
R when the vehicle is stationary, depress the
brake pedal and keep it depressed.
R engage park position P.
R release the brake pedal.
R remove the Start/Stop button from the
ignition lock.
Automatic transmission141Driving and parkingZ

Problems with fuel and the fuel tankProblemPossible causes/consequences and M SolutionsFuel is leaking from the
vehicle.GRisk of explosion or fire
The fuel line or the fuel tank is defective.
XTurn the SmartKey to position 0(Y page 132) in the ignition lock
immediately and remove it.XDo not restart the engine under any circumstances.XConsult a qualified specialist workshop.The fuel filler flap
cannot be opened.The fuel filler flap is not unlocked.
or
The SmartKey battery is discharged.XUnlock the vehicle using the mechanical key ( Y page 75).XOpen the trunk lid.XManually unlock the fuel filler flap using the emergency release
( Y page 149).The fuel filler flap is unlocked, but the opening mechanism is
jammed.XConsult a qualified specialist workshop.Parking
Important safety notes
GWARNING
Do not park this vehicle in areas where
combustible materials can come into contact
with the hot exhaust system. Do not park the
vehicle on dry grassland or harvested grain
fields. Combustible materials, such as grass,
hay or leaves could be ignited by the hot
exhaust system and cause a vehicle fire.
Unintended vehicle movement can cause
serious personal injury or damage to the
vehicle or the vehicle drivetrain. To reduce
such risks, always do the following before
turning off the engine and leaving the vehicle:
R keep your right foot on the brake pedal.
R engage the parking brake.
R shift the automatic transmission to park
position P.
R
slowly release the brake pedal.
R when parked on an incline, always turn the
front wheels towards the road curb.
R turn the SmartKey in the ignition lock to
position 0 and remove the SmartKey from
the ignition lock, or press the KEYLESS-GO
Start/Stop button.
R take the SmartKey with you and lock the
vehicle when leaving.
Switching off the engine
Important safety notes
GWARNING
Do not turn off the engine before the vehicle
has come to a complete stop. With the engine
not running, there is no power assistance for
the brake and steering systems. In this case,
it is important to keep in mind that a
150ParkingDriving and parking

considerably higher degree of effort is
necessary to brake and steer the vehicle.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.
Vehicles with automatic transmission
XApply the parking brake firmly.XStandard vehicles: shift the transmission
to P.
Selector lever in AMG vehicles with P button
XAMG vehicles: press P button :.
Using the SmartKey
XTurn the SmartKey to position 0 in the
ignition lock and remove it.
The immobilizer is activated.
i If you turn off the engine with the
SmartKey and then remove it from the
ignition lock or open a front door, the
automatic transmission shifts to P
automatically.
Using KEYLESS-GOXPress the Start/Stop button (Y page 133).
The engine stops and all the indicator
lamps in the instrument cluster go out.
i When the driver's door is closed, this
corresponds to SmartKey position 1. When
the driver's door is open, it corresponds to
SmartKey position 0 or "SmartKey
removed".
i If you use the Start/Stop button to switch
off the engine, the automatic transmission
shifts to N automatically. If you then open
the driver's or front-passenger door, the
automatic transmission shifts to P.
i The engine can be turned off while the
vehicle is in motion by pressing and holding
the Start/Stop button for three seconds.
This function operates independently from
the ECO start/stop automatic engine
switch-off function.
Parking brake
GWARNING
Engaging the parking brake while the vehicle
is in motion can cause the rear wheels to lock
up. You could lose control of the vehicle and
cause an accident. In addition, the vehicle's
brake lights do not light up when the parking
brake is engaged.
GWARNING
When leaving the vehicle, always remove the
SmartKey from the starter switch, take it with
you, and lock the vehicle. Do not leave
children unattended in the vehicle, or with
access to an unlocked vehicle. Children could
release the parking brake and/or shift the
automatic transmission out of park position
P , either of which could result in an accident
and/or serious personal injury.
Parking151Driving and parkingZ

Wet roadsGWARNING
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
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 roads
GWARNING
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 ) while the parking brake is being tested
on a brake dynamometer.
Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system.
Driving tips153Driving and parkingZ

! 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 parking brake on a brake
dynamometer.
R you intend to have the vehicle towed with
one of the axles raised.
Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system.
If your brake system is subject only to
moderate loads, you should test the
functionality of your brakes at regular
intervals by pressing firmly on the brake pedal
at high speeds. This improves the grip of the
brake pads.GWARNING
Make sure that you do not endanger other
road users when you apply the brakes.
You can find a description of Brake Assist
(BAS) on ( Y page 62) or of BAS PLUS on
( Y page 62).
Winter driving
General information
GWARNING
If the vehicle becomes trapped in snow,
ensure that snow is kept away from the
exhaust pipe and from around the vehicle as
long as the engine is running. Otherwise,
poisonous carbon monoxide (CO) may enter
the vehicle, resulting in loss of consciousness
and even death.
To assure sufficient fresh air ventilation, open
a window slightly on the side of the vehicle
not facing the wind.
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 "Winter operation"
section ( Y page 316).
Driving with summer tires
Observe the notes in the "Winter operation"
section ( Y page 316).
Slippery road surfaces
GWARNING
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Indicated temperatures just above the
freezing point do not guarantee that the road
surface is free of ice. The road may still be icy,
especially in wooded areas or on bridges.
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.
Drive particularly carefully on slippery road
surfaces. Avoid sudden acceleration, steering
and braking maneuvers. Do not use cruise
control or DISTRONIC PLUS.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:
XShift the transmission to position N.
i
For more information on driving with
snow chains, see ( Y page 317).
GWARNING
Make sure that you do not endanger other
road users when you apply the brakes.
154Driving tipsDriving and parking