MERCEDES-BENZ AMG GT ROADSTER 2019 Owner's Manual

Electric parking brake
General notes G
WARNING
If you leave children unsupervised in the vehi- cle, they could set it in motion by, for example:
R release the parking brake.
R shift the automatic transmission out of the
parking position P.
R start the engine.
In addition, they may operate vehicle equip-
ment and become trapped. 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 unsupervised in the vehicle.
The function of the electric parking brake is
dependent on the on-board voltage. If the on-
board voltage is low or there is a malfunction in
the system, it may not be possible to apply the
released parking brake.
X If this is the case, only park the vehicle on
level ground and secure it to prevent it rolling
away.
X Shift the automatic transmission to position
005D.
It may not be possible to release an applied
parking brake if the on-board voltage is low or
there is a malfunction in the system. Contact a
qualified specialist workshop.
The electric parking brake performs a function
test at regular intervals while the engine is
switched off. The sounds that can be heard while
this is occurring are normal. Applying or releasing manually X
To apply: push handle 0043.
When the electric parking brake is applied,
the red 0049(USA only) or 0024(Canada
only) indicator lamp lights up in the instru-
ment cluster.
The electric parking brake can also be applied when the SmartKey is in position 0092.
X To release: pull handle0043.
The red 0049(USA only) or 0024(Canada
only) indicator lamp in the instrument cluster goes out.
The electric parking brake can only be released:
R if the ignition is switched on using the Start/
Stop button or
R the SmartKey is in SmartKey position 0047or
0048 in the ignition lock (Y page 111)
Applying automatically The electric parking brake is automatically
applied when the transmission is in position 005D
and:
R the engine is switched off or
R the driver is not wearing a seat belt and the
driver's door is opened
To prevent the electric parking brake from being
automatically applied, pull handle 0043.
The electric parking brake is also applied auto-
matically in the following cases if:
R Active Distance Assist DISTRONIC brings the
vehicle to a standstill or
R the HOLD function is keeping the vehicle sta-
tionary Parking
129Driving and parking Z

In addition, at least one of the following condi-
tions must be fulfilled:
R there is a system malfunction
R the power supply is insufficient
R the vehicle is stationary for a lengthy period
The red 0049(USA only) or 0024(Canada only)
indicator lamp in the instrument cluster lights
up.
The electric parking brake is not automatically
applied if the engine is switched off by the ECO
start/stop function.
Releasing automatically The electric parking brake is released when the
following conditions are fulfilled:
R The engine is running
R The seat belt tongue is engaged in the belt
buckle
R the transmission is in position 005Bor005E and
you depress the accelerator pedal or shift
from position 005Dto005B or005E
R if the transmission is in position 005E, the trunk
lid must be closed
If the seat belt tongue is not engaged in the seat belt buckle, the following conditions must be
fulfilled:
R the driver's door and front-passenger door
are closed
R you move the transmission out of position 005D
or you have previously driven at a speed
above 2 mph (3 km/h)
R if the transmission is in position 005E, the trunk
lid must be closed
When the electric parking brake is released, the red 0049 (USA only) or 0024(Canada only) indi-
cator lamp goes out in the instrument cluster.
Emergency braking The vehicle can also be braked during an emer-
gency by using the electric parking brake.
X While driving, push handle 0043of the electric
parking brake (Y page 129).
The vehicle is braked as long as you keep
handle 0043of the electric parking brake
pressed. The longer electric parking brake
handle 0043is depressed, the greater the brak-
ing force. During braking:
R a warning tone sounds
R the Please Release Parking Brake
Please Release Parking Brake mes-
sage appears
R the red 0049(USA only) or 0024(Canada
only) indicator lamp in the instrument cluster
flashes
When the vehicle has been braked to a stand-
still, the electric parking brake is applied. Parking the vehicle for a long period
General notes If you leave the vehicle parked for longer than
four weeks, the battery may be damaged by
exhaustive discharging.
If you leave the vehicle parked for longer than six weeks, the vehicle may suffer damage as a
result of lack of use.
X Visit a qualified specialist workshop and seek
advice.
Trickle charging the on-board electrical
system battery The battery may drain if the vehicle is left sta-
tionary for long periods. In this case, Mercedes-
Benz recommends attaching the trickle charger to 12 V socket 0043in the trunk.
i A trickle charger and further information
can be obtained from a qualified specialist
workshop.
X Switch the ignition off.
X Open the trunk lid. 130
ParkingDriving and parking

X
Connect the cable provided in the trunk to the
trickle charger.
X Connect the trickle charger to 12 V socket 0043.
Consult the manufacturer's operating instruc- tions on how to do so.
The trunk lid can be closed, even if a trickle
charger is connected. Make sure that the con-
nector for both the connector cables is outside
of the vehicle.
The connector can then separate if the vehicle is moved, even if you forget to disconnect the con-
nector cables. This prevents damaging the
cables and the trickle charger.
A trickle charger connected to 12 V socket 0043
only maintains the current charge level of the
vehicle's electrical system battery. If the vehi-
cle's electrical system battery is discharged, it
needs to be charged with a battery charger. Driving tips
General driving tips
Important safety notes G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect, 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 you operate mobile communication equip-
ment when driving, you may be distracted
from the traffic situation. You could also lose
control of the vehicle. There is a risk of an
accident.
Only operate this equipment when the vehicle is stationary.
Observe the legal requirements for the country
in which you are driving. Some jurisdictions pro-
hibit the driver from using a mobile phone while driving a vehicle. If you make a call while driving, always use
hands-free mode. Only operate the telephone
when the traffic situation permits. If you are
unsure, pull over to a safe location and stop
before operating the telephone.
Bear in mind that at a speed of only 30 mph
(approximately 50 km/h), the vehicle covers a
distance of 44 ft (approximately 14
m)per sec-
ond.
Drive sensibly – save fuel Observe the following tips to save fuel:
X The tires should always be inflated to the rec-
ommended tire pressure.
X Remove unnecessary loads.
X Warm up the engine at low engine speeds.
X Avoid frequent acceleration or braking.
X Have all service and maintenance work car-
ried out at the specified intervals.
Fuel consumption also increases when driving in
cold weather, in stop-start traffic and in hilly ter- rain.
Drinking and driving G
WARNING
Drinking and driving and/or taking drugs and driving are very dangerous combinations.
Even a small amount of alcohol or drugs can
affect your reflexes, perceptions and judg-
ment.
The possibility of a serious or even fatal acci-
dent is greatly increased when you drink or
take drugs and drive.
Do not drink or take drugs and drive or allow
anyone to drive who has been drinking or tak-
ing drugs.
Emission control G
DANGER
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases is hazardous to health
and can result in poisoning. There is a risk of
fatal injury. Therefore, never leave the engine Driving tips
131Driving and parking
Z

running an enclosed space without adequate
ventilation.
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 if
they are serviced exactly in accordance with the manufacturer's specifications. Always have
work on the engine carried out at a qualified
specialist workshop. Mercedes-Benz recom-
mends 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.
The engine settings must not be changed under
any circumstances. Furthermore, all specific
service work must be carried out at regular
intervals and in accordance with the Mercedes- Benz service requirements.
You can obtain current information concerning
the servicing of your vehicle at any time from a
qualified specialist workshop. This could be an
overview of the maintenance work or any addi-
tional maintenance work, for example. Braking
Important safety notes G
WARNING
If you shift down on a slippery road surface in an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on a slippery road surface.
Downhill gradients !
On long and steep gradients, you must
reduce the load on the brakes by shifting to a
lower gear in good time. This allows you to
take advantage of the engine's braking effect.
This helps you to avoid overheating the
brakes and wearing them out excessively.
When you take advantage of engine braking, 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 war-
ranty.
Heavy and light loads G
WARNING
If you rest your foot on the brake pedal while
driving, the braking system can overheat. This increases the stopping distance and can even
cause the braking system to fail. There is a
risk of an accident.
Never use the brake pedal as a footrest. Never
depress the brake pedal and the accelerator
pedal at the same time.
! Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads.
If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately. Drive on for a short while. This allows the airflow to
cool the brakes more quickly.
Wet roads If you have driven for a long time in heavy rain
without braking, there may be a delayed reac-
tion from the brakes when braking for the first
time. This may also occur after the vehicle has
been washed or driven through deep water.
You have to depress the brake pedal more
firmly. Maintain a greater distance from the
vehicle 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 If you drive on salted roads, a layer of salt resi-
due may form on the brake discs and brake
pads. This can result in a significantly longer
braking distance.132
Driving tipsDriving and parking

Observe the following rules when driving on salt-
treated roads:
R In order to prevent any salt build-up, apply the
brakes occasionally while paying attention to
the traffic conditions.
R Carefully depress the brake pedal and the
beginning and end of a journey.
R Maintain a greater distance to the vehicle
ahead.
Servicing the brakes !
The brake fluid level may be too low, if:
R if the red brake warning lamp lights up in
the instrument cluster and
R you hear a warning tone while the engine is
running
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. Consult a qualified specialist workshop to
arrange this.
All checks and maintenance work on the brake
system must be carried out at a qualified spe-
cialist workshop.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop.
If the brake system has only been subject to
moderate loads, you should test the functional-
ity of your brakes at regular intervals.
Information on BAS (Brake Assist) (Y page 59).
For safety reasons, Mercedes-Benz recom-
mends only installing the following brake disks
and brake pads/linings:
R brake disks that have been approved by
Mercedes-Benz
R brake pads/linings that have been approved
by Mercedes-Benz or that are of an equivalent
standard of quality
Other brake disks or brake pads/linings can
compromise the safety of your vehicle.
Always replace all brake disks and brake pads/
linings on an axle at the same time. Always
install new brake pads/linings when replacing
brake disks.
The vehicle is equipped with lightweight brake
disks to which the wheel assembly with rim and threaded connection is matched. The use of brake disks other than those
approved by Mercedes-Benz can change the
track width and is subject to approval, if appli-
cable.
Shock-type loads when handling the brake
discs, such as when changing wheels, can lead
to a reduction in comfort when driving with light-
weight brake discs. Avoid shock-type loads on
the lightweight brake disks, particularly on the
brake plate.
Mercedes-Benz recommends that you only use
brake fluid that has been specially approved for your vehicle by Mercedes-Benz, or which corre-
sponds to an equivalent quality standard. Brake fluid which has not been approved for
Mercedes-Benz vehicles or which is not of an
equivalent quality could affect your vehicle's
operating safety.
AMG high-performance and ceramic
brakes The AMG brake systems are designed for heavy
loads. This may lead to noise when braking. This
will depend on:
R Speed
R Braking force
R Environmental conditions, such as tempera-
ture and humidity
The wear of individual components of the brake system, such as the brake pads/linings or brake
discs, depends on the individual driving style
and operating conditions.
For this reason, it is impossible to state a mile-
age that will be valid under all circumstances. An aggressive driving style will lead to high wear.
You can obtain more information on this from a qualified specialist workshop.
New and replaced brake pads and discs only
reach their optimum braking effect after several
hundred kilometers of driving. Compensate for
this by applying greater force to the brake pedal.
Keep this in mind, and adapt your driving and
braking accordingly during this break-in period.
Excessive heavy braking results in correspond-
ingly high brake wear. Observe the brake wear
warning lamp in the instrument cluster and note
any brake status messages in the multifunction
display. Especially for high performance driving,
it is important to maintain and have the brake
system checked regularly. Driving tips
133Driving and parking Z

Driving on wet roads
Hydroplaning If water has accumulated to a certain depth on
the road surface, there is a danger of hydro-
planing occurring, even if:
R you drive at low speeds
R the tires have adequate tread depth
For this reason, in the event of heavy rain or in
conditions in which hydroplaning may occur,
you must drive in the following manner:
R lower your speed
R avoid ruts
R avoid sudden steering movements
R brake carefully
Driving on flooded roads !
Do not drive through flooded areas. Check
the depth of any water before driving through
it. Drive slowly through standing water. Oth-
erwise, water could enter the vehicle interior
or engine compartment. It can then damage
the engine's or automatic transmission's
electronic components. It can also be sucked
in by the engine's air intake connection and
cause engine damage. Winter driving
G
WARNING
If you shift down on a slippery road surface in an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on a slippery road surface. G
DANGER
If the exhaust pipe is blocked or adequate
ventilation is not possible, poisonous gases
such as carbon monoxide (CO) may enter the vehicle. This is the case, e.g. if the vehicle
becomes trapped in snow. There is a risk of
fatal injury. If you leave the engine or the auxiliary heating
running, make sure the exhaust pipe and area
around the vehicle are clear of snow. To
ensure an adequate supply of fresh air, open a window on the side of the vehicle that is not
facing into the wind.
Have your vehicle winter-proofed at a qualified
specialist workshop at the onset of winter.
Drive particularly carefully on slippery road sur- faces. Avoid sudden acceleration, steering and
braking maneuvers. Do not use cruise control.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:
X Shift the transmission to position 005C.
The outside temperature indicator is not
designed to serve as an ice-warning device and
is therefore unsuitable for that purpose.
Changes in the outside temperature are dis-
played after a short delay.
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. The vehicle could
skid if you fail to adapt your driving style. Always
adapt your driving style and drive at a speed to
suit the prevailing weather conditions.
You should pay special attention to road condi-
tions when temperatures are around freezing
point.
Further information on driving with snow chains (Y page 265).
Further information on driving with summer
tires (Y page 265).
Observe the notes in the "Winter operation" sec-
tion (Y page 265). Driving systems
Cruise control
General notes Cruise control maintains a constant road speed
for you. It brakes automatically in order to avoid
exceeding the set speed. Change into a lower
gear in good time on long and steep downhill
gradients. This is especially important if the
vehicle is laden. By doing so, you will make use of the braking effect of the engine. This relieves
the load on the brake system and prevents the 134
Driving syste
msDriving and parking

brakes from overheating and wearing too
quickly.
Use cruise control only if road and traffic con-
ditions make it appropriate to maintain a steady speed for a prolonged period. You can store any
road speed above 20 mph (30 km/h).
Cruise control lever 0043
Activates or increases speed
0044 Activates at the current speed or last stored
speed
0087 Activates or reduces speed
0085 Deactivates cruise control
When you activate cruise control, the stored
speed is shown in the multifunction display for
five seconds. In addition, the 00ECsymbol
appears in the multifunction display.
Speedometer with segments: when cruise
control is activated, the segments from the
stored speed to the end of the scale light up.
Storing and maintaining the current
speed You can store the current speed if you are driv-
ing faster than 20 mph (30 km/
h).X
Accelerate the vehicle to the desired speed.
X Briefly press the cruise control lever up 0043or
down 0044.
X Remove your foot from the accelerator pedal.
Cruise control is activated. The vehicle auto-
matically maintains the stored speed.
i Cruise control may be unable to maintain
the stored speed on uphill gradients. The
stored speed is resumed when the gradient
evens out. Cruise control maintains the
stored speed on downhill gradients by auto-
matically applying the brakes.
Storing, maintaining and calling up a
speed G
WARNING
If you call up the stored speed and it is lower
than the current speed, the vehicle deceler-
ates. If you do not know the stored speed, the vehicle could decelerate unexpectedly. There
is a risk of an accident.
Pay attention to the road and traffic condi-
tions before calling up the stored speed. If you do not know the stored speed, store the
desired speed again. X
Briefly pull the cruise control lever towards
you 0043.
X Remove your foot from the accelerator pedal.
The first time cruise control is activated, it
stores the current speed or regulates the
speed of the vehicle to the previously stored
speed. Driving systems
135Driving and parking Z

Setting a speed
Keep in mind that it may take a brief moment
until the vehicle has accelerated or braked to
the speed set.
X Press the cruise control lever up 0043for a
higher speed or down 0044for a lower speed.
X To adjust the set speed in 1 mph incre-
ments (1 km/h increments):
briefly press
the cruise control lever up 0043or down 0044to
the pressure point.
Every time the cruise control lever is pressed
up 0043 or down 0044the last speed stored is
increased or reduced.
X To adjust the set speed in 5 mph incre-
ments
(10 km/h increments): briefly press
the cruise control lever up 0043or down 0044
beyond the pressure point.
Every time the cruise control lever is pressed
up 0043 or down 0044the last speed stored is
increased or reduced.
i Cruise control is not deactivated if you
depress the accelerator pedal. If you acceler-
ate to overtake, cruise control adjusts the
vehicle's speed to the last speed stored after
you have finished overtaking.
Deactivating cruise control There are several ways to deactivate cruise con-
trol:
X Briefly press the cruise control lever for-
wards 0043.
or
X Brake.
Cruise control is automatically deactivated
under the following conditions:
R the electric parking brake is applied.
R you are driving slower than 20 mph
(30 km/h).
R if ESP ®
intervenes or you deactivate ESP ®
.
R you shift the transmission to position 005C
while driving.
If cruise control is deactivated, a warning tone
sounds. You will see the Cruise Control Off Cruise Control Off
message in the multifunction display for approx-
imately five seconds.
i When you switch off the engine, the last
speed stored is cleared. Active Distance Assist DISTRONIC
General notes Active Distance Assist DISTRONIC regulates the
speed and automatically helps you maintain the
distance from the vehicle detected in front.
Vehicles are detected with the aid of the radar
sensor system. Active Distance Assist
DISTRONIC brakes automatically so that the set
speed is not exceeded.
Change into a lower gear in good time on long
and steep downhill gradients. This is especially
important if the vehicle is laden. By doing so, you will make use of the braking effect of the engine.
This relieves the load on the brake system and
prevents the brakes from overheating and wear- ing too quickly.
If Active Distance Assist DISTRONIC detects
that there is a risk of a collision with the vehicle
in front, you will be warned visually and audibly.
Active Distance Assist DISTRONIC cannot pre-
vent a collision without your intervention. An
intermittent warning tone will then sound and
the distance warning lamp will light up in the
instrument cluster. Brake immediately in order
to increase the distance to the vehicle in front or take evasive action provided it is safe to do so. 136
Driving systemsDriving and parking

Active Distance Assist DISTRONIC operates in
the speed range between 0 mph (0 km/h) and
120 mph (200 km/h).
Do not use Active Distance Assist DISTRONIC
while driving on roads with steep gradients.
As Active Distance Assist DISTRONIC transmits
radar waves, it can be mistaken for the radar
detectors used by the traffic authorities. You
can refer to the relevant chapter in the Opera-
tor's Manual if questions are asked about this.
i USA only: This device has been approved by
the FCC as a "Vehicular Radar System". The
radar sensor is intended for use in an auto-
motive radar system only. Removal, tamper-
ing, or altering of the device will void any war-
ranties, and is not permitted by the FCC. Do
not tamper with, alter, or use in any non-
approved way.
Any unauthorized modification to this device
could void the user's authority to operate the equipment.
i Canada only: This device complies with
RSS-210 of Industry Canada. Operation is
subject to the following two conditions:
1. This device may not cause interference,
and
2. This device must accept any interference
received, including interference that may
cause undesired operation of the device.
Removal, tampering, or altering of the device will void any warranties, and is not permitted.
Do not tamper with, alter, or use in any non-
approved way.
Any unauthorized modification to this device
could void the user's authority to operate the
equipment.
Important safety notes G
WARNING
Active Distance Assist DISTRONIC does not
react to:
R people or animals
R stationary objects in the road, e.g. stopped
or parked vehicles
R oncoming vehicles and crossing traffic
As a result, Active Distance Assist DISTRONIC
may neither give warnings nor intervene in
such situations. There is a risk of an accident. Always pay careful attention to the traffic sit-
uation and be ready to brake. G
WARNING
Active Distance Assist DISTRONIC cannot
always clearly identify other road users and
complex traffic situations.
In such cases, Active Distance Assist
DISTRONIC can:
R give an unnecessary warning and then
brake the vehicle
R neither give a warning nor intervene
R accelerate or brake unexpectedly
There is a risk of an accident.
Continue to drive carefully and be ready to
brake, especially if Active Distance Assist
DISTRONIC warns you. G
WARNING
DISTRONIC PLUS brakes your vehicle with up to 50% of the maximum possible deceleration.
If this braking force is insufficient, DISTRONIC
PLUS warns you visually and audibly. There is a risk of an accident.
In such cases, apply the brakes yourself and
try to take evasive action.
! When Active Distance Assist DISTRONIC or
the HOLD function is activated, the vehicle
brakes automatically in certain situations.
To avoid damage to the vehicle, deactivate
Active Distance Assist DISTRONIC and the
HOLD function in the following or similar sit-
uations:
R when towing the vehicle
R in the car wash
Active Distance Assist DISTRONIC can neither
reduce the risk of an accident if you fail to adapt
your driving style, nor override the laws of phys- ics. Active Distance Assist DISTRONIC cannot
take into account road, weather or traffic con-
ditions. Active Distance Assist DISTRONIC is
only an aid. You are responsible for the distance
to the vehicle in front, for vehicle speed, for
braking in good time and for staying in your lane. Driving systems
137Driving and parking Z

Do not use Active Distance Assist DISTRONIC:
R In road and traffic conditions which do not
allow you to maintain a constant speed, e.g. in
heavy traffic or on winding roads
R on slippery road surfaces. Braking or accel-
erating could cause the drive wheels to lose
traction and the vehicle could then skid
R when there is poor visibility, e.g. due to fog,
heavy rain or snow
Active Distance Assist DISTRONIC may not
detect narrow vehicles driving in front, e.g.
motorcycles, or vehicles driving in a staggered
formation.
In particular, the detection of obstacles can be
impaired if:
R There is dirt on the sensors or anything else
covering the sensors
R There is snow or heavy rain
R There is interference by other radar sources
R There are strong radar reflections, for exam-
ple, in parking garages
If Active Distance Assist DISTRONIC no longer
detects a vehicle in front, Distance Pilot
DISTRONIC may unexpectedly accelerate to the
speed stored.
This speed may:
R be too high if you are driving in a turning lane
or an exit lane
R be so high in the right lane that you pass vehi-
cles driving on the left (in countries where
they drive on the right)
R be so high in the left lane that you pass vehi-
cles driving on the right (right-hand drive
countries)
If there is a change of drivers, advise the new
driver of the speed stored. Cruise control lever 0043
Activates or increases speed
0044 Activates or reduces speed
0087 Deactivates Active Distance Assist
DISTRONIC
0085 Activates at the current speed or last stored
speed
0083 Sets a specified minimum distance
Activating Active Distance Assist
DISTRONIC Activation conditions
To activate Active Distance Assist DISTRONIC,
the following conditions must be fulfilled:
R the engine must be started. It may take up to
two minutes of driving before Active Distance Assist DISTRONIC is ready for use.
R the electric parking brake must be released.
R ESP ®
must be active, but not intervening.
R the transmission must be in position 005B.
R the driver's door must be closed when you
shift from 005Dto005B or your seat belt must be
fastened.
R the front-passenger door and rear doors must
be closed. 138
Driving systemsDriving an
d parking