2018 MERCEDES-BENZ CLS automatic transmission

Problem
Possible causes/consequences and P Solutions
The engine cannot be
started using the Smart-
Key. The on-board voltage is too low. X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work: X
Check the starter battery and charge it if necessary ( Y
page 284).
or X
Jump-start the vehicle ( Y
page 285).
or X
Consult a qualified specialist workshop.
The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle. The vehicle is locked. X
Unlock the vehicle and try to start the vehicle again.
There is interference from a powerful source of radio waves. X
Start your vehicle with the SmartKey in the ignition lock.
You have lost a Smart-
Key. X
Have the SmartKey deactivated at a qualified specialist workshop. X
Report the loss immediately to the vehicle insurers. X
If necessary, have the locks changed as well.
You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers. X
If necessary, have the locks changed as well.
Doors
Important safety notes
G WARNING
If children are left unsupervised in the vehicle,
they could: R
open the doors, thus endangering other
people or road users. R
get out and disrupt traffic. R
operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they: R
release the parking brake. R
shifting the automatic transmission out of
park position PR
Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
Unlocking and opening doors from
the inside You can open a door from inside the vehicle
even if it has been locked.
If the vehicle has previously been locked from
the outside, opening a door from the inside will
trigger the anti-theft alarm system. Switch off
the alarm ( Y
page 75).
You can only open the rear doors from inside the
vehicle if they are not secured by the child-proof
locks ( Y
page 63). Doors 81
Opening and closing Z

for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving.
G WARNING
If the parking brake has not been fully
released when driving, the parking brake can: R
overheat and cause a fire R
lose its hold function.
There is a risk of fire and an accident. Release
the parking brake fully before driving off.
! Do not warm up the engine with the vehicle
stationary. Drive off immediately. Avoid high
engine speeds and driving at full throttle until
the engine has reached its operating temper-
ature.
Only shift the automatic transmission to the
desired drive position when the vehicle is sta-
tionary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery roads.
You could otherwise damage the drive train.
! Mercedes-AMG vehicles: at low engine oil
temperatures below 68 ‡ (+20 †), the max-
imum engine speed is restricted in order to
protect the engine. To protect the engine and
maintain smooth engine operation, avoid driv-
ing at full throttle when the engine is cold. Key positions
SmartKey
Z
To remove the SmartKey
(shift the transmission to position P )G
Power supply for some consumers, such as
the windshield wipers H
Ignition (power supply for all consumers)
and drive position I
To start the engine
i The SmartKey can be turned in the ignition
lock even if it is not the correct SmartKey for
the vehicle. The ignition is not switched on.
The engine cannot be started.
KEYLESS-GO
General notes Vehicles with KEYLESS-GO are equipped with
SmartKeys featuring the integrated KEYLESS-
GO function and a detachable Start/Stop but-
ton.
The Start/Stop button must be inserted in the
ignition lock and the SmartKey must be in the
vehicle.
When you insert the Start/Stop button into the
ignition lock, the system needs approximately
two seconds recognition time. You can then use
the Start/Stop button.
Pressing the Start/Stop button several times in
succession corresponds to the different Smart-
Key positions in the ignition lock. This is only the
case if you are not depressing the brake pedal.
If you depress the brake pedal and press the
Start/Stop button, the engine starts immedi-
ately.
A check which periodically establishes a radio
connection between the vehicle and the Smart-
Key determines whether a valid SmartKey is in Driving 123
Driving and parking Z

the vehicle. This occurs, for example, when
starting the engine.
To start the vehicle without actively using the
SmartKey: R
the Start/Stop button must be inserted in the
ignition lock. R
the SmartKey must be in the vehicle. R
the vehicle must not be locked with the
SmartKey or KEYLESS-GO ( Y
page 76).
Do not keep the KEYLESS-GO key: R
with electronic devices, e.g. a mobile phone
or another SmartKey. R
with metallic objects, e.g. coins or metal foil. R
inside metallic objects, e.g. a metal case.
This can affect the functionality of KEYLESS-GO.
If you lock the vehicle with the SmartKey's
remote control or with KEYLESS-GO, after a
short time: R
you will not be able to switch on the ignition
with the Start/Stop button. R
you will not be able to start the engine with the
Start/Stop button until the vehicle is
unlocked again.
The engine can be switched off while the vehicle
is in motion by pressing and holding the Start/
Stop button for three seconds. This function
operates independently of the ECO start/stop
automatic engine switch-off function.
Key positions with KEYLESS-GO
C
Start/Stop button
D
Ignition lock
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light
up. Indicator and warning lamps, see
( Y
page 226). If Start/Stop button C has not yet been
pressed, this corresponds to the SmartKey
being removed from the ignition. X
To switch on the power supply: press
Start/Stop button C once.
The power supply is switched on. You can now
activate the windshield wipers, for example.
The power supply is switched off again if: R
the driver's door is opened and R
you press Start/Stop button C twice when in
this position X
To switch on the ignition: press Start/Stop
button C twice.
The ignition is switched on.
If you press Start/Stop button C once when
in this position, the ignition is deactivated
again.
Removing the Start/Stop button You can remove the Start/Stop button from the
ignition lock and start the vehicle as normal
using the SmartKey.
It is only possible to switch between Start/Stop
button mode and SmartKey operation when the
transmission is in position P .X
Remove Start/Stop button C from ignition
lock D .
You do not have to remove the Start/Stop but-
ton from the ignition lock when you leave the
vehi cle. You should, however, always take the
SmartKey
with you when leaving the vehicle. As
long as the SmartKey is in the vehicle: R
the vehicle can be started using the Start/
Stop button R
the electrically powered equipment can be
operated
Starting the engine
Important safety notes
G WARNING
If children are left unsupervised in the vehicle,
they could: R
open the doors, thus endangering other
people or road users. R
get out and disrupt traffic. R
operate the vehicle's equipment.124
Driving
Dr ivi ng an d parking

Additionally, children could set the vehicle in
motion if, for example, they: R
release the parking brake. R
shifting the automatic transmission out of
park position PR
Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
G WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There
is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation.
G WARNING
Flammable materials introduced through
environmental influence or by animals can
ignite if in contact with the exhaust system or
parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
General notes
i The catalytic converter is preheated for up
to 30 seconds after a cold start. The sound of
the engine may change during this time.
Automatic transmission X
Shift the transmission to position P .
The transmission position display in the mul-
tifunction display shows P .
i You can start the engine in transmission
position P and N . Starting procedure with the SmartKey
i To start the engine using the SmartKey
instead of KEYLESS-GO, pull the Start/Stop
button out of the ignition lock. X
Turn the SmartKey to position 3 in the ignition
lock ( Y
page 123 )a nd release it as soon as the
engine is running.
Using KEYLESS-GO to start the engine
i The Start/Stop button can be used to start
the vehicle manually without inserting the
SmartKey into the ignition lock. The Start/
Stop button must be inserted in the ignition
lock and the SmartKey must be in the vehicle.
This mode for starting the engine operates
independently of the ECO start/stop auto-
matic engine start function. X
Depress the brake pedal and keep it
depressed. X
Press the Start/Stop button once
( Y
page 123).
The engine starts.
Pulling away
General notes
G WARNING
If the engine speed is above the idling speed
and you engage transmission position D or R ,
the vehicle could pull away suddenly. There is
a risk of an accident.
When engaging transmission position D or R ,
always firmly depress the brake pedal and do
not simultaneously accelerate.
! If a warning tone sounds and the Release
Park. Brake message appears in the multi-
function display, the parking brake is still
applied. Release the parking brake.
Depress the accelerator carefully when pulling
away.
The vehicle locks centrally once you have pulled
away. The locking knobs in the doors drop down.
You can open the doors from the inside at any
time.
You can also deactivate the automatic locking
feature ( Y
page 199).Driving 125
Driving an d parking Z

It is only possible to shift the transmission from
position P to the desired position if you depress
the brake pedal. If the brake pedal is not
depressed, the DIRECT SELECT lever can still be
moved but the parking lock remains engaged.
i Upshifts take place at higher engine speeds
after a cold start. This helps the catalytic con-
verter to reach its operating temperature
more quickly.
Hill start assist Hill start assist helps you when pulling away for-
wards or in reverse on an uphill gradient. It holds
the vehicle for a short time after you have
removed your foot from the brake pedal. This
gives you enough time to move your foot from
the brake pedal to the accelerator pedal and to
depress it before the vehicle begins to roll.
G WARNING
After a short time, hill start assist will no lon-
ger brake your vehicle and it could roll away.
There is a risk of an accident and injury.
Therefore, quickly move your foot from the
brake pedal to the accelerator pedal. Never
leave the vehicle when it is held by hill start
assist.
Hill start assist is not active if: R
you are pulling away on a level road or on a
downhill gradient. R
the transmission is in position N .R
the parking brake is applied. R
ESP ®
is malfunctioning.
ECO start/stop function
Introduction The ECO start/stop function switches the
engine off automatically if the vehicle is stopped
under certain conditions.
The engine starts automatically when the driver
wants to pull away again. The ECO start/stop
function thereby helps you to reduce the fuel
consumption and emissions of your vehicle. Important safety notes
G WARNING
If the engine is switched off automatically and
you exit the vehicle, the engine is restarted
automatically. The vehicle may begin moving.
There is a risk of accident and injury.
If you wish to exit the vehicle, always turn off
the ignition and secure the vehicle against
rolling away.
General notes
C
ECO start/stop display
The ECO start/stop function is activated when
you start the engine.
If the engine has been switched off automati-
cally by the ECO start/stop function, the

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
the driver's door is closed and the driver's
seat belt is fastened
i All of the vehicle's systems remain active
when the engine is stopped automatically.
i The HOLD function can also be activated if
the engine has been switched off automati-
cally. 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 deac-
tivated.
Automatic engine switch-off can take place a
maximum of four times in a row (initial stop, then
three subsequent stops).
Mercedes-AMG vehicles: the number of con-
secutive automatic engine switch-offs is unlimi-
ted.
All other models: automatic engine switch-off
can take place a maximum of four times in a row
(initial switch-off, then three subsequent switch-
offs).
Automatic engine start The engine starts automatically if: R
you switch off the ECO start/stop function by
pressing the ECO button R
in transmission position D or N the brake
pedal is released and the HOLD function is not
active R
you depress the accelerator pedal R
you engage reverse gear RR
you move the transmission out of position PR
you switch to drive program S , S+ or M
(Mercedes-AMG vehicles) R
you unfasten your seat belt or open the driv-
er's door R
the vehicle starts to roll R
the brake system requires this R
the temperature in the vehicle interior devi-
ates from the set range R
the system detects moisture on the wind-
shield when the air-conditioning system is
switched on R
the battery's condition of charge is too low i Shifting the transmission to position P does
not start the engine.
Deactivating or activating the ECO
start/stop function Mercedes-AMG vehicles X
To deactivate: in drive program C , press ECO
button C .
or X
Switch to drive program S , S+ or M
( Y
page 134).
Indicator lamp D goes out.X
To activate: press ECO button C .
Indicator lamp D lights up.
If drive program S , S+ or M is active, the auto-
matic transmission switches to drive program
C .
If indicator lamp D 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 vehi-
cle stops.
All other models Driving 127
Dr ivi ng an d parking Z

Problem
Possible causes/consequences and P Solutions
The engine is not running
smoothly and is misfir-
ing. There is a malfunction in the engine electronics or in a mechanical
component of the engine management system. X
Only depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic converter
and damage it. X
Have the cause rectified immediately at a qualified specialist work-
shop.
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. X
Stop as soon as possible and allow the engine and the coolant to
cool down. X
Check the coolant level ( Y
page 268). Observe the warning notes
as you do so and add coolant if necessary.
Automatic transmission
Important safety notes
G WARNING
If the engine speed is above the idling speed
and you engage transmission position D or R ,
the vehicle could pull away suddenly. There is
a risk of an accident.
When engaging transmission position D or R ,
always firmly depress the brake pedal and do
not simultaneously accelerate.
G WARNING
The automatic transmission switches to neu-
tral position N when you switch off the engine.
The vehicle may roll away. There is a risk of an
accident.
After switching off the engine, always switch
to parking position P . Prevent the parked vehi-
cle from rolling away by applying the parking
brake. Selector lever (Mercedes-AMG vehi-
cles)
Overview of transmission positions
]
Park position with parking lock ^
Reverse gear \\
Neutral [
Drive
Transmission position and drive pro-
gram display The current transmission position and drive pro-
gram appear in the multifunction display.Automatic transmission 129
Driving and parking Z

C
Transmission position displayD
Drive program display
Additionally, displays next to the selector lever
mark the current transmission position.
The indicators light up when the Smartkey is
inserted into the ignition lock. The indicators go
out when the Smartkey is removed from the
ignition lock.
If the transmission position display in the mul-
tifunction display is not working, you should pull
away carefully to check whether the desired
transmission position is engaged. Ideally, you
should select transmission position D and drive
program C or S .
Engaging park position P
X
When the vehicle is stationary, press but-
ton C . DIRECT SELECT lever
Overview of transmission positions
]
Park position with parking lock ^
Reverse gear \\
Neutral [
Drive
The DIRECT SELECT lever is on the right of the
steering column.
The DIRECT SELECT lever always returns to its
original position. The current transmission posi-
tion P , R , N or D appears in the transmission
position display in the multifunction display
( Y
page 130).
Transmission position and drive pro-
gram display The current transmission position and drive pro-
gram appear in the multifunction display.
C
Transmission position display
D
Drive program display
The arrows in the transmission position display
show how and into which transmission positions
you can shift using the DIRECT SELECT lever.
If the transmission position display in the mul-
tifunction display is not working, you should pull
away carefully to check whether the desired
transmission position is engaged. Ideally, you
should select transmission position D and drive
program E or S .130
Automatic transmission
Driving and parking