2018 MERCEDES-BENZ C-CLASS CABRIOLET Owner's Manual

If your vehicle with trailer (vehicle/trailer com-
bination) begins to lurch, you can only stabilize
the vehicle/trailer combination by depressing
the brake firmly.
ESP
®trailer stabilization is active above speeds
of approximately 40 mph (65 km/h).
ESP
®trailer stabilization does not work if ESP®
is deactivated or malfunctioning.
Crosswind Assist
General information
Strong crosswind gusts can impair the ability of
your vehicle to drive straight ahead. The cross-
wind driving assistance function integrated in
ESP
®noticeably reduces these impairments.
ESP®intervenes automatically according to the
direction and intensity of the crosswinds affect-
ing your vehicle.
ESP
®intervenes with stabilizing braking to
assist you in keeping the vehicle in the lane.
Crosswind Assist is active at vehicle speeds
above 50 mph (80 km/h) when driving straight
ahead or cornering gently.
Important safety notes
Crosswind Assist does not work if ESP®is
switched off or deactivated because of a mal-
function.
EBD (electronic brake force distribu-
tion)
General information
EBD monitors and controls the brake pressure
on the rear wheels to improve driving stability
while braking.
Important safety notes
iObserve the "Important safety notes" sec-
tion (Ypage 64).
GWARNING
If EBD is malfunctioning, the rear wheels can
lock, e.g. under full braking. This increases the
risk of skidding and an accident.
You should therefore adapt your driving style
to the different handling characteristics. Have
the brake system checked at a qualified spe-
cialist workshop.
Observe information regarding indicator and
warning lamps (
Ypage 244) as well as display
messages (Ypage 215).
ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety and
offers increased braking comfort. In addition to
the braking function, ADAPTIVE BRAKE also has
the HOLD function (
Ypage 161) and hill start
assist (Ypage 127).
Active Brake Assist with cross-traffic
function
General information
iObserve the important safety notes in the
"Driving safety systems" section (Ypage 64).
Active Brake Assist with cross-traffic function
can help you to minimize the risk of a collision
with a vehicle in front or a pedestrian and reduce
the effects of such a collision. If the Active Brake
Assist with cross-traffic function detects a risk
of collision, you will be warned visually and
acoustically and, if necessary, your brake appli-
cation will be assisted according to the situa-
tion. If you do not react, the system can also
react by braking automatically. In the event of a
detected risk of collision due to crossing traffic,
you will also be visually and acoustically warned as well as assisted by the brake boosting effect
according to the situation.
Active Brake Assist with cross-traffic function is
only available in vehicles with the Driving Assis-
tance Plus package.
For Active Brake Assist with cross-traffic func-
tion to assist you when driving, the radar sensor
system and the camera system must be opera-
tional.
If the radar sensor system or the camera systemis malfunctioning, Active Brake Assist with
cross-traffic function is restricted or no longer
available. The brake system is still available with
complete brake boosting effect and BAS.
The radar sensor system and camera system
help Active Brake Assist with cross-traffic func-
Driving safety systems71
Safety
Z

tion to detect obstacles that are in the path of
your vehicle for an extended period of time.
In addition, pedestrians in the path of your vehi-
cle can be detected.
Active Brake Assist with cross-traffic function
detects pedestrians using typical characteris-
tics such as body contours and the posture of a
person standing upright.
iObserve the restrictions described in the
"Important safety notes" section
(
Ypage 72).
Important safety notes
GWARNING
Active Brake Assist with cross-traffic function will initially brake your vehicle by a partial
application of the brakes if a danger of colli-
sion is detected. There may be a collision
unless you brake yourself. Even after subse-
quent full application of the brakes a collision
cannot always be avoided, particularly when
approaching at too high a speed. There is a
risk of an accident.
Always apply the brakes yourself and try to
take evasive action, provided it is safe to do
so.
In the event of a partial application of the brakes,
the vehicle is braked with up to 50% of the full
braking pressure.
GWARNING
Active Brake Assist with cross-traffic function cannot always clearly identify objects and
complex traffic situations.
In such cases, Active Brake Assist with cross-
traffic function might:
Rissue an unnecessary warning or engage
Rneither give a warning nor intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and be prepared to brake, especially
if Active Brake Assist with cross-traffic func-
tion alerts you. Terminate the intervention in a
non-critical driving situation.
GWARNING
Active Brake Assist with cross-traffic function cannot always clearly identify people, partic-
ularly if they are moving. Active Brake Assist
with cross-traffic function cannot intervene in
these cases. There is a risk of an accident.
Always pay particular attention to the traffic
situation and be prepared to brake, especially
if Active Brake Assist with cross-traffic func-
tion alerts you.
In order to maintain the appropriate distance to
the vehicle in front and thus prevent a collision,
you must apply the brakes yourself.
GWARNING
Active Brake Assist with cross-traffic function does not react:
Rto small people, e.g. children
Rto animals
Rto oncoming vehicles
Rwhen cornering
As a result, Active Brake Assist with cross-
traffic function may not warn you or engage in
all critical situations. There is a risk of an acci-
dent.
Always pay careful attention to the traffic sit- uation and be ready to brake.
In the event of snowfall or heavy rain, the rec-
ognition can be impaired.
Recognition by the radar sensor system is also
impaired if:
Rthere is dirt on the sensors or anything else
covering the sensors
Rthere is interference by other radar sources
Rthere are strong radar reflections, for exam-
ple in parking garages
Ra narrow vehicle is traveling in front, e.g. a
motorbike
Ra vehicle is traveling in front on a different line
Rvehicles moving quickly into the radar sensor
system detection range
72Driving safet ysystem s
Safety

Recognition by thecamera system is also
impaire din th eevent of:
Rdirt on th ecamera or if th ecamera is covered
Rglar eon th ecamera system, e.g. from th esun
bein glow in th esk y
Rdarkness
Ror if:
-pedestrian smov equickly, e.g. int oth epat h
of th evehicl e
-thecamera system no longer recognizes a
pedestrian as aperson due to special cloth -
ing or other objects
-a pedestrian is concealed by other objects
-th etypical outlin eof apedestrian is no t
distinguishable from th ebackgroun d
Followin gdamag eto th efron ten dof th evehicle,
hav eth econfiguration and operation of th e
radar sensor schecke dat aqualified specialist
workshop. This also applie sto collision sat slow
speeds wher ethere is no visible damag eto th e
fron tof th evehicle.
Followin gdamag eto th ewindshield, hav eth e
configuration and operation of th ecamera sys-
te m checke dat aqualified specialist workshop.
Function
XTo activate or deactivate: activateor deac -
tivat eActive Brake Assist wit hcross-traffic
function usin gth eon-board computer
(
Ypage 205).
If Active Brake Assist wit hcross-traffic func-
tion is deactivated, th eæ symbol appear s
on th emultifunction display.
Starting at aspee dof aroun d 4mph (7 km/h),
this function warn syou if you are rapidly
approachin g avehicl ein front. An intermittent
warning tone will then soun dand th e· dis-
tance warning lamp will ligh tup in th einstru-
men tcluster.
XBrake immediately to defuse th esituation .
or
XTak eevasive action provide dit is saf eto do
so.
Active Brake Assist wit hcross-traffic function
can also brak eth evehicl eautomatically under
th efollowin gconditions:
Rth edriver and fron tpassenger hav etheir seat
belt sfastene d
Rthevehicl espee dis between approximately
4 mph (7 km/ h) and 124 mph (200 km/h) Up to a speed of approximately 44 mph
(70 km/h), Active Brake Assist with cross-traffic
function may react to:
Rstationary objects in the path of your vehicle,
e.g. stopped or parked vehicles
Rpedestrians in the path of your vehicle
iIf there is an increased risk of a collision,
preventive passenger protection measures
(PRE-SAFE
®) are triggered (Ypage 58).
If the risk of collision with the vehicle in front
remai ns a
nd you do not brake, take evasive
action or accelerate significantly, the vehicle
may perform automatic emergency braking, up
to the point of full brake application. Automatic emergency braking is not performed until imme-
diately prior to an imminent accident.
If you apply the brake yourself in a critical sit-
uation or during autonomous braking, situation-
dependent braking assistance is implemented.
If necessary, this increases the brake pressure
up to full brake application.
To avoid a collision, Active Brake Assist with
cross-traffic function calculates the brake force
necessary if:
Ryou approach an obstacle, and
RActive Brake Assist with cross-traffic functionhas detected a risk of a collision
When driving at a speed under 20 mph
(30 km/h): if you depress the brake pedal,
Active Brake Assist with cross-traffic function is
activated. The increase in brake pressure from
Active Brake Assist with cross-traffic function is
carried out at the last possible moment.
When driving at a speed above 20 mph
(30 km/h): if you depress the brake pedal
sharply, Active Brake Assist with cross-traffic
function automatically increases the brake pres-
sure to a degree suited to the traffic situation.
Active Brake Assist with cross-traffic function
provides braking assistance in hazardous situa-
tions with vehicles in front within a speed range
between 4 mph (7 km/h) and 155 mph
(250 km/h).
Driving safety systems73
Safety
Z

Up to a speed of approximately 44 mph
(70 km/h) the Active Brake Assist with cross-
traffic function assists you with braking in haz-
ardous situations with:
Rstationary obstacles in the path of the vehicle,
e.g. stopped or parked vehicles
Rstationary pedestrians in the path of the vehi-
cle
Robstacles crossing your path that move in the
detection range of the sensors and are detec-
ted
XKeep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
You can prevent the intervention of Active Brake
Assist with cross-traffic function at any time by:
Rdepressing the accelerator pedal further.
Ractivating kickdown.
Rreleasing the brake pedal
The braking application of Active Brake Assist
with cross-traffic function is ended automati-
cally if:
Ryou maneuver to avoid the obstacle.
Rthere is no longer a risk of collision.
Ran obstacle is no longer detected in front of
your vehicle.
STEER CONTROL
General information
STEER CONTROL helps you by transmitting a
noticeable steering force to the steering wheel
in the direction required for vehicle stabilization.
This steering assistance is provided in particular
if:
Rboth right wheels or both left wheels are on a
wet or slippery road surface when you brake
Rthe vehicle begins to skid
Important safety notes
iObserve the "Important safety notes" sec-
tion (Ypage 64). No steering support is provided from STEER
CONTROL, if:
RESP®is deactivated
RESP®is malfunctioning
Rthe steering is malfunctioning
If ESP®is malfunctioning, you will be assisted
further by the electrical power steering.
Protection against theft
Immobilizer
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
XTo activate with the SmartKey: remove the
SmartKey from the ignition lock.
XTo activate with KEYLESS-GO start-func-
tion or KEYLESS-GO: switch the ignition off
and open the driver's door.
XTo deactivate: switch on the ignition.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Anyone
can start the engine if a valid SmartKey has been
left inside the vehicle.
iThe immobilizer is always deactivated when
you start the engine.
In the event that the engine cannot be started
(yet the vehicle's battery is charged), the sys- tem is not operational. Contact an authorized
Mercedes-Benz Center or call
1-800-FOR-MERCedes (in the USA) or
1-800-387-0100 (in Canada).
ATA (anti-theft alarm system)
74Protection against theft
Safety

XTo arm:lock the vehicle with the SmartKey or
KEYLESS-GO.
Indicator lamp :flashes. The alarm system
is armed after approximately ten seconds.
XTo disarm: unlock the vehicle with the Smart-
Key or KEYLESS-GO.
or
XInsert the SmartKey into the ignition lock.
or
XVehicles with KEYLESS-GO start function
or KEYLESS-GO: press the Start/Stop but-
ton.
The SmartKey must be in the vehicle.
A visual and audible alarm is triggered if the
alarm system is armed and you open:
Ra door
Rthe vehicle with the mechanical key
Rthe trunk lid
Rthe hood
Rthe stowage compartment/telephone com-
partment under the armrest in vehicles with
automatic transmission
XTo stop the alarm with the SmartKey:
press the %or& button on the Smart-
Key.
The alarm is stopped.
or
XVehicles with KEYLESS-GO start-function
or KEYLESS-GO: remove the Start/Stop but-
ton from the ignition lock (
Ypage 124).
XInsert the SmartKey into the ignition lock.
The alarm is stopped.
XTo stop the alarm using KEYLESS-GO:
grasp the outside door handle. The SmartKey
must be outside the vehicle.
The alarm is stopped.
or
XPress the Start/Stop button on the dash-
board. The SmartKey must be inside the vehi-
cle.
The alarm is stopped.
The alarm is not switched off, even if you close
the op en d
oor that triggered it, for example.
iIf the alarm continues for more than
30 seconds, the mbrace emergency call sys-
tem automatically notifies the Customer
Assistance Center. This is done either by text
message or data connection. The emergency call system sends a message
or establishes a data connection provided
that:
Ryou have subscribed to the mbrace service.
Rthe mbrace service has been activated
properly.
Rthe necessary mobile phone network is
available.
Protection against theft75
Safety
Z

SmartKey
Important safety notes
GWARNING
If children are left unsupervised in the vehicle,
they could:
Ropen the doors, thus endangering other
people or road users.
Rget out and disrupt traffic.
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake.
Rshifting the automatic transmission out of
park position P
RStart 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.
GWARNING
If you attach heavy or large objects to the
SmartKey, the SmartKey could be uninten-
tionally turned in the ignition lock. This could
cause the engine to be switched off. There is a risk of an accident.
Do not attach any heavy or large objects to the
SmartKey. Remove any bulky key rings before
inserting the SmartKey into the ignition lock.
!Keep the SmartKey away from strong mag-
netic fields. Otherwise, the remote control
function could be affected.
Strong magnetic fields can occur in the vicin-
ity of powerful electrical installations.
Do not keep the SmartKey:
Rwith electronic devices, e.g. a mobile phone
or another SmartKey.
Rwith metallic objects, e.g. coins or metal foil.
Rinside metallic objects, e.g. a metal case.
This can affect the functionality of the Smart- Key. Vehicles with KEYLESS-GO start function:
do
not keep the SmartKey in the cargo compart-
ment. Otherwise, the SmartKey may not be
detected, e.g. when starting the engine using
the Start/Stop button.
A brief radio connection between the vehicle
and the SmartKey determines whether a valid
SmartKey is in, or in the direct vicinity of, the
vehicle. This occurs, for example:
Rwhen starting the engine
Rwhile driving
Rwhen the external door handles are touched
Rduring convenience closing
SmartKey functions
:& Locks the vehicle
;FOpens the trunk lid
=%Unlocks the vehicle
XTo unlock centrally: press the%button.
If you do not open the vehicle within approx-
imately 40 seconds of unlocking:
Rthe vehicle is locked again.
Rprotection against theft is reactivated.
XTo lock centrally: press the&button.
The SmartKey centrally locks and unlocks the
following components:
Rthe doors
Rthe trunk lid
Rthe glove box
Rthe fuel filler flap
The turn signals flash once when unlocking and
three times when locking.
You can also set an audible signal to confirm
that the vehicle has been locked. The audible
signal can be activated and deactivated via the
76SmartKey
Opening and closing

multimedia system; see the Digital Operator's
Manual.
You will receive visual and acoustic locking con-
firmation if all components were able to be
locked.
When the locator lighting is activated via the
multimedia system, it lights up when it is dark
after the vehicle is unlocked with the SmartKey;
see the Digital Operator's Manual.
XTo open the trunk lid automatically from
outside the vehicle:press and hold theF
button until the trunk lid opens.
KEYLESS-GO
General notes
Bear in mind that the engine can be started by
any of the vehicle occupants if there is a Smart-
Key in the vehicle (
Ypage 125).
Locking/unlocking centrally
You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you only need carry the
SmartKey with you. You can combine the func-
tions of KEYLESS-GO with those of a conven-
tional SmartKey. Unlock the vehicle by using
KEYLESS-GO, for instance, and lock it using the
& button on the SmartKey.
The driver's door and the door at which the han-
dle is used, must both be closed. The SmartKey
must be outside the vehicle. When locking or
unlocking with KEYLESS-GO, the distance
between the SmartKey and the corresponding
door handle must not be greater than 3 ft (1 m).
A brief radio connection between the vehicle
and the SmartKey determines whether a valid
SmartKey is in, or in the direct vicinity of, the
vehicle. This occurs, for example:
Rwhen starting the engine
Rwhile driving
Rwhen the external door handles are touched
Rduring convenience closing
XTo unlock the vehicle: touch the inner sur-
face of the door handle.
XTo lock the vehicle: touch sensor surface :
or ;.
Make sure that you do not touch the inner
surface of the door handle.
XConvenience closing feature: touch
recessed sensor surface ;for an extended
period.
Deactivating and activating
If you do not intend to use a SmartKey for an
extended period of time, you can deactivate the
KEYLESS-GO function of the SmartKey. The
SmartKey will then use very little power, thereby
conserving battery power. For the purposes of
activation/deactivation, the vehicle must not be
nearby.
XTo deactivate: press the&button on the
SmartKey twice in rapid succession.
The battery check lamp (
Ypage 79) of the
SmartKey flashes twice briefly and lights up
once, then KEYLESS-GO is deactivated.
XTo activate: press any button on the Smart-
Key.
or
XInsert the SmartKey into the ignition lock.
KEYLESS-GO and all of its associated features
are available again.
KEYLESS-GO start function
General notes
Bear in mind that the engine can be started by
any of the vehicle occupants if there is a Smart-
Key in the vehicle (
Ypage 125).
SmartKey77
Opening and closing
Z

Changing the settings of the locking
system
You can change the settings of the locking sys-
tem. This means that only the driver's door and
the fuel filler flap are unlocked when the vehicle
is unlocked. This is useful if you frequently travel
alone.
XTo change the setting:press and hold down
the % and& buttons simultaneously
for approximately six seconds until the bat-
tery check lamp (
Ypage 79) flashes twice.
If the setting of the locking system is changed
within the signal range of the vehicle, pressing
the & or% button:
Rlocks or
Runlocks the vehicle
The SmartKey now functions as follows:
XTo unlock: press the%button once.
XTo unlock centrally: press the%button
twice.
XTo lock: press the &button.
XTo restore the factory settings: press and
hold the %and& buttons simultane-
ously for approximately six seconds until the
battery check lamp (
Ypage 79) flashes
twice.
The KEYLESS-GO functions can be changed as
follows:
XTo unlock the driver's door: touch the inner
surface of the door handle on the driver's
door.
XTo unlock centrally: touch the inner surface
of the front-passenger door handle.
XTo lock centrally: touch the outer sensor
surface on one of the door handles.
Mechanical key
General notes
If the vehicle can no longer be locked or
unlocked with the SmartKey or KEYLESS-GO,
use the mechanical key.
If you use the mechanical key to unlock and
open the driver's door, the anti-theft alarm sys-
tem will be triggered. Switch off the alarm
(
Ypage 74). If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked auto-
matically.
XTo unlock the fuel filler flap:
insert the
SmartKey into the ignition lock.
Removing the mechanical key
XPush release catch :in the direction of the
arrow and at the same time remove mechan- ical key ;from the SmartKey.
Further information on locking/unlocking the
driver's door (
Ypage 83).
Inserting the mechanical key
XPush mechanical key ;completely into the
SmartKey until it engages and release
catch :is back in its basic position.
SmartKey battery
Important safety notes
GWARNING
Batteries contain toxic and corrosive substan- ces. If batteries are swallowed, it can result in
severe health problems. There is a risk of fatalinjury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
HEnvironmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them with
78SmartKey
Opening and closing