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Acoustic signals and display
The interval between the acoustic signals becomes shorter as the clearance is
reduced. A continuous tone sounds from a distance of approx. 30 cm - danger
area. From this moment on do not continue driving!
For information on setting the acoustic signals and a description of the Info-
tainment display, see » Infotainment manual , chapter Vehicle settings (button
CAR) .
Towing a trailer
On vehicles equipped with a factory-fitted towing device, only system areas A
and
B
» Fig. 114 are active when towing a trailer.
Note
The signal tones for front obstacle recognition are factory-set to be higher
than for rear obstacle recognition.
Activation/deactivation
Read and observe
and on page 117 first.
The system is automatically activated by selecting reverse gear or pressing
the symbol button
» Fig. 114 on page 117 .
This is confirmed by a short acoustic signal (the symbol in the button lights
up).
On vehicles with Version 1, the system can be deactivated by moving out of re-
verse gear.
For vehicles with Version 2, the system is deactivated by pressing the symbol
button or automatically at a speed over 10 km/h (the symbol
in the but-
ton goes out).
Displaying an error
If a warning signal sounds for about 3 seconds after activating the system and
there is no obstacle close to your car, this indicates a system fault. The fault is
also indicated by the symbol flashing in the button. Seek help from a spe-
cialist garage.
Note
The system can only be activated via the symbol button at a speed of below
10 km/hr.Automatic system activation when moving forwardFig. 116
Infotainment display: Display
with automatic activation
Read and observe and on page 117 first.
Automatic activation takes place at a speed below around 10 km/h under the following conditions.
› The distance to the obstacle at the front is less than around 90 cm.
› The distance to the obstacle at the front is less than around 30 cm.
After activation, the following is shown in the left pane of the Infotainment
display » Fig. 116 .
Acoustic signals are sounded as of a distance from the obstacle of around
50 cm.
Automatic display can be activated/deactivated in the Infotainment » Infotain-
ment manual , chapter Vehicle settings (CAR button) .
Cruise control system
Introduction
This chapter contains information on the following subjects:
Functioning
119
Operating Description
119
The Cruise Control System (CCS) maintains a set speed without you having to
actuate the accelerator pedal.
The status where the CCS maintains the speed is referred to hereinafter as the
control .
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WARNING■The CCS only serves as an assistance and does not relieve the driver of
the responsibility for the vehicle operation.■
Always adjust the speed and driving style to the current visibility, weath-
er, road and traffic conditions.
■
After pressing the clutch pedal, no interrupted control occurs! For exam-
ple, if a different gear is engaged and the clutch pedal is released, control is
continued.
Functioning
Fig. 117
Maxi DOT display: Examples of status displays the CCS
Fig. 118
Segment display: Examples of status displays the CCS
Read and observe
on page 119 first.
GRA status displays » Fig. 117 , » Fig. 118
Speed set, but control is inactive.
Control is active.
No speed set.
System fault - seek assistance from a specialist garage immediately.
Basic requirements for starting the control The CCS is activated.
On vehicles with a manual transmission , the second gear or higher is en-
gaged.
On vehicles with an automatic transmission , the selector lever is in the D/
S position or in the Tiptronic position.
The current speed is higher than approx. 20 km/h.
This is only possible within the range which is permitted by the power output
and braking power of the engine.WARNINGIf the engine power and engine braking effect is insufficient to maintain
the set speed, vehicle operation must be taken over!
Operating Description
Fig. 119
Cruise control system controls
Read and observe on page 119 first.
Overview of the CCS controls » Fig. 119ADeactivate CCS (delete set speed) Interrupt control (sprung position) Activate CCS (control deactivated)BTake control again a)
/ Increase speedCStart control / reduce speedDSwitching between GRA and Speed Limiter » page 120a)
If no speed is set the current speed is adopted.
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At the start of the regulation the GRA regulates the vehicle to the current
speed, and this speed is shown on the instrument cluster display. The warning
light
illuminates in the instrument cluster.
Automatic control interruption
Automatic control interruption occurs if any of the following conditions are
met.
› The brake pedal is operated.
› When one of the brake assist systems (e.g. ESC) intervenes.
› Through an airbag deployment.
› The key
is actuated.WARNING■
Always deactivate the cruise control system after use to prevent the sys-
tem being enabled unintentionally.■
Control may only be resumed if the set speed is not too high for the cur-
rent traffic conditions.
Note
■ During control, speed can be increased by pressing the accelerator pedal. Re-
leasing the accelerator pedal will cause the speed to drop again to the set
speed.■
By pressing the
button during the regulation this is cancelled and the
Speed Limiter is activated.
Speed Limiter
Introduction
This chapter contains information on the following subjects:
Operation
120
Operation description
121
The Speed Limiter limits the maximum driving speed to the set speed limit.
This limit can only be exceeded by depressing the accelerator pedal fully.
The condition in which the Speed Limiter monitors a potential set speed limit
excess is referred to as Regulation.
WARNING■
The Speed Limiter only serves as an assistance and does not relieve the
driver of the responsibility for the vehicle operation.■
Always adjust the speed and driving style to the current visibility, weath-
er, road and traffic conditions.
Operation
Fig. 120
Maxi DOT display: Examples of Speed Limiter status displays.
Fig. 121
Segment display: Examples of Speed Limiter status displays.
Read and observe
on page 120 first.
Status display of the Speed Limiter » Fig. 120, » Fig. 121
Speed limit set, but regulation is inactive.
Control is active.
No speed limit set.
System fault - seek assistance from a specialist garage immediately.
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Basic requirements for starting the controlThe Speed Limiter is activated.
The current speed is higher than approx. 30 km/h.
Operation description
Fig. 122
Operating elements of the Speed Limiter: Vehicle Speed Limiter /
vehicle with GRA and Speed Limiter
Read and observe
on page 120 first.
Overview of the control elements of the Speed Limiter » Fig. 122ASpeed Limiter disable (set limit delete) Interrupt control (sprung position) Activate Speed Limiter (regulation deactivated) For vehicles with GRA and Speed Limiter the GRA is activated by
the switch in the
position by being adjusted. The activation of
the Speed Limiter occurs only after pressing the button
.BTake control again a)
/ Increase speed - short press (in increments
of 1 km/h), long press (in increments of 10 km/h)CStart regulation / reduce speed - short press (in increments of 1
km/h), long press (in increments of 10 km/h)Dswitch between GRA » page 118and Speed Limitera)
If no speed limit is set, the current speed is set as the speed limit.
At the start of the regulation, the current speed is set as the speed limit and
displayed in the instrument cluster display. The warning light illuminates in
the instrument cluster.
Exceeding the speed limit during the regulation
If exceeding the speed limit is required during the regulation, for example
when overtaking, then the accelerator pedal is to be fully pressed.
When exceeding the speed limit, an acoustic signal sounds and the warning
light
in the instrument cluster flashes.
The regulation is resumed once the speed has fallen below the set limit.
CAUTION
When driving downhill, exceeding the set speed limit may occur. When exceed-
ing the limit, an acoustic signal sounds and the warning light in the instru-
ment cluster flashes.
Note
By pressing the button during the regulation this is cancelled and the GRA
is activated.
Front Assistant
Introduction
This chapter contains information on the following subjects:
Radar sensor
122
Operation
122
Proximity warning (dangerous proximity)
123
Warning and automatic braking
123
Activating/deactivating
123
Information messages
124
The Front Assistant (from here on only referred to as the system) warns you of
the danger of a collision with a vehicle or another obstacle in front of the vehi-
cle and tries to avoid a collision or mitigate its consequences by automatically
applying the brakes as appropriate.
The area in front of the vehicle is monitored by a radar sensor » Fig. 123 on
page 122 .
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WARNING■The system only serves as an assistance and does not relieve the driver
of the responsibility for the vehicle operation.■
The system has physical and system-related limitations. For this reason,
the driver may experience some undesired or delayed system responses in
certain situations. You should therefore always be alert and ready to inter-
vene!
■
Always adapt your speed and safety proximity to the vehicle ahead to the
current visibility, weather, road and traffic conditions.
■
The increased passenger protection afforded through the system must
not tempt you to take greater risks than otherwise – risk of accident!
■
The system does not respond to crossing or oncoming objects.
CAUTION
In case of failure of more than one brake light on the vehicle or on the electri-
cally connected trailer, the system becomes unavailable.
Radar sensor
Fig. 123
Mounting location of the radar
sensor
Read and observe and on page 122 first.
The radar sensor » Fig. 123(Hereinafter referred to simply as the sensor) may
detect objects by radiating and receiving electromagnetic waves.
The sensor function may be impaired in the events of one of the following.
› The sensor is soiled by mud, snow and the like.
› The area in front and around the senor is obscured by labels, auxiliary lights
and similar.
› When visibility is poor, (e.g. fog, heavy rain, thick snowfall).
If the sensor is dirty or covered, the corresponding message appears on the
display of the instrument cluster » page 124, Information messages .
WARNING■
If you suspect that the sensor is damaged, deactivate the system. Have
the sensor checked by a specialist garage.■
The sensor can become misaligned by collisions or by damage to the front
of the vehicle, the wheel arch or the underside of the vehicle. This can lead
to impaired function of the sensor - risk of accidents! Have the sensor
checked by a specialist garage.
■
The area in front and around the senor should not be obscured by labels,
auxiliary lights and similar. This can lead to impaired function of the sensor
- risk of accidents!
CAUTION
Remove the snow with a brush and the ice with a solvent-free de-icer.
Operation
Fig. 124
Instrument cluster display: Note
(dangerous distance) / warning
or emergency braking at low
speed
Read and observe and on page 122 first.
The system support is provided in the following manner.
› Alerts you about a dangerous proximity to the vehicle ahead.
› Warns you of an impending collision.
› Prepares the brakes for emergency braking prior to a detected danger.
› Assists with a brake action triggered by the driver.
› If the driver fails to respond to a detected danger, an automatic braking ac-
tion is performed.
The system can work only if the following basic conditions are met. The system is activated.
TheTCS is activated » page 115, Traction Control System (TCS) .
The vehicle is moving forwards at a speed of more than approx. 5 km/h.
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NoteThe system can be impaired or may not be available, for example when driving
in “sharp ”curves or with an ESC engagement » page 115.
Proximity warning (dangerous proximity)
Read and observe
and on page 122 first.
If a safe distance to the vehicle ahead is not maintained, the display of the in-
strument cluster shows the symbol
» Fig. 124 on page 122 -
.
Immediately increase the proximity if the current traffic situation allows you
to do so!
The proximity at which the warning is displayed depends on the current speed.
The warning may occur when driving between about 60 km/h and 210 km/h.
Warning and automatic braking
Read and observe
and on page 122 first.
Emergency braking at low speed
In a driving speed range of about 5 km/h to about 30 km/h the automatic brak-
ing action is not preceded by a warning. With an immediate impact hazard au-
tomatic braking is done with the breaking force increasing in stages.
With automatic braking the symbol appears » Fig. 124
on page 122 -
in the
display.
Advance warning
If the system detects a risk of collision, the symbol » Fig. 124
on page 122 -
appears in the display and you will hear an acoustic signal.
At the same time, the braking system is prepared for possible emergency brak- ing.
The pre-warning display can occur in the following situations. › If there is a risk of collision with a moving obstacle in a driving speed range of
about 30 km/h to about 210 km/h.
› There is a risk of a collision with a stationary moving obstacle in a vehicle
speed range of approximately 30 km/h to about 85 km/h.
With a warning the brake pedal must be pressed or the moving obstacle is to
be avoided!
Acute alert
If the driver does not react to the advance warning, the system briefly applies
the brake automatically via an active brake intervention to draw attention to
the potential danger of a collision again.
Automatic Braking
If the driver fails to respond to the acute warning, the system starts to apply
the brakes automatically with increasing stopping power in several stages.
Brake assist
If the driver brakes inadequate with an impending collision, the system auto-
matically increases braking force.
The braking assistance only occurs as long as the brake pedal is being firmly
pressed down.
Note
■ If an automatic brake intervention is triggered by the system, the pressure in
the brake system increases and the brake pedal cannot be operated with the
normal pedal stroke.■
The automatic braking interventions can be cancelled by pressing the accel-
erator pedal or by steering intervention.
Activating/deactivating
Read and observe
and on page 122 first.
The function is automatically activated each time the ignition is switched on.
The system should only be disabled in exceptional cases »
.
The activation or deactivation of the system can be done in one of two ways.
› In the menu item
Assist systemsthe display of the instrument cluster
» page 45 , MAXI DOT display .
› In Infotainment
» Operating instructions for Infotainment , chapter Vehicle
settings (CAR button) .
The following functions can be activated or deactivated separately in infotain-
ment.
› Distance warning
› Advance warning
Upon deactivation of these functions remains disabled even after switching
off and switching on the ignition.
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WARNINGIn the following situations, Front Assistant should be switched off for safe-
ty reasons.■
When the vehicle is being towed away.
■
When the vehicle is on a rolling test bench.
■
If an unfounded warning or a system action was taken.
■
When on a truck, or a car ferry service or similar.
Information messages
Read and observe
and on page 122 first.
The warning symbols are shown in the instrument cluster display. Front Assist: No sensor view.
The sensor is soiled or covered.
Stop the car, switch off the engine and clean the sensor or eliminate the dis-
turbance causing the lack of visibility » Fig. 123 on page 122 .
If the message appears again after starting the engine, the system should be disabled » page 123 . Seek help from a specialist garage.
Front Assist not available.
The system is not available for an unknown reason.
Stop the vehicle, switch off the engine and then start it again.
If the message appears again after starting the engine, the system should be disabled » page 123 . Seek help from a specialist garage.
START-STOP
Introduction
This chapter contains information on the following subjects:
Operating conditions for the system
124
Operation in vehicles with manual gearbox
125
Operation in vehicles with automatic gearbox
125
System conditioned automatic start-up
126
Manually deactivating/activating
126
Information messages
126The START-STOP system (hereinafter referred to just as the system) reduces
fuel consumption and polluting emissions and CO 2 emissions by turning the
engine off, e.g. when stopping at traffic lights, and starting the engine again
when moving off.WARNING■ Never let the vehicle roll with the engine switched off.■The brake servo unit and power steering only operate if the engine is run-
ning.
Operating conditions for the system
Fig. 125
Engine is automatically switched
off / automatic engine cut off is
not possible
Read and observe on page 124 first.
For the system-dependent automatic engine shutdown to operate, the follow-
ing conditions must be met.
The driver's door is closed.
The driver has fastened the seat belt.
The bonnet is closed.
The driving speed exceeded 4 km/h after the last stop.
No trailer is coupled.
Some additional conditions for the system to function cannot be either influ-
enced or recognised by the driver. Therefore, the system can react differently
in situations which are identical from the driver's view.
If, after stopping the vehicle, the check icon
» Fig. 125 appears on the dis-
play, then the conditions for automatic engine shutdown are not met.
Running the engine is essential, for example, for the following reasons.
› The engine temperature for the proper function of the system has not yet
been reached.
› The charge state of the vehicle battery is too low.
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›The current consumption is too high.
› High air-conditioning or heating capacity (high fan speed, big difference be-
tween the desired and actual indoor temperature).
Information about the current status of the system can be displayed in the In-
fotainment display » operating instructions for Infotainment , chapter Vehicle
settings (CAR button) .
Note
■
If the vehicle remains outdoors for a long time in minus temperatures or in
direct sunlight, it can take several hours until the internal temperature of the
vehicle battery reaches a suitable temperature for proper operation of the sys-
tem.■
If the driver's seat belt is removed for more than approx. 30 seconds or the
driver's door is opened during stop mode, the engine will have to be started
manually.
■
After the manual engine start and with a manual gearbox the automatic en-
gine shutdown can take place only when a minimum distance required for the
system function has been covered.
Operation in vehicles with manual gearbox
Read and observe
on page 124 first.
In compliance with the operating conditions, automatic engine shutdown / au-
tomatic engine start takes place as described.
Automatic engine shut down
›
Stop the vehicle.
›
Shift the gear lever to Neutral.
›
Release the clutch pedal.
Automatic engine shutdown then occurs and the indicator symbol appears in
the display
» Fig. 125 on page 124 .
Automatic engine start
›
Depress the clutch pedal.
The automatic re-start process takes place and the indicator symbol goes
out.
Operation in vehicles with automatic gearbox
Read and observe
on page 124 first.
In compliance with the operating conditions, automatic engine shutdown / au-
tomatic engine start takes place as described.
Automatic engine shut down
›
Bring the vehicle to a stop and depress the brake pedal.
Automatic engine shutdown then occurs and the indicator symbol appears in
the display
» Fig. 125 on page 124 .
Automatic engine start
›
Release the brake pedal.
The automatic re-start process takes place and the indicator symbol goes
out.
Further information on automatic transmission
Engine shut down takes place when the selector lever is in positions P, D/S , N
and in Tiptronic mode.
When the selector lever is in position P, the engine remains shut down even
after you release the brake pedal. The engine starts automatically by pressing
the gas pedal or by moving the selector lever into a different mode and releas-
ing the brake pedal.
If the engine is off due to the automatic and the selector lever is put to the R
position, then the automatic start up of the engine.
If the gear selector is moved from position R to the position D/S or N the vehi-
cle must reach a speed of more than 10 km/h before the automatic engine
shutdown starts.
There is no automatic engine shutdown when the system detects a vehicle
moving due to a large steering angle.
No automatic engine shutdown takes place when the vehicle is moving at low
speed (e.g. during a traffic jam or when turning) and remains stationary after
pressing the brake pedal lightly. Automatic engine shutdown takes place if you
press the brake pedal down with more force.
125Assist systems