260 Driving systems
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The distance warning sound continues until the driver
activates the brake pedal, or the preset distance is
obtained. As soon as the preset distance is obtained, the
distance warning lamp goes out.Caution!
If the driver’s foot is not fully removed from the
accelerator pedal, the Distronic control system will be
overridden and it will not regulate the preset vehicle
speed and following distance. The vehicle speed and
following distance is determined only by the accelerator
pedal position.
Distronic works on steep uphill and downhill gradients
by downshifting gears and applying the brakes to
maintain the speed selected by the driver. The
transmission will upshift again once the gradient evens
out.
The speed can be increased (e.g. for passing) by using
the accelerator. After the accelerator is released, the
previously set speed will be resumed automatically.
Distronic is deactivated if a vehicle in front causes your
vehicle to slow down to less than approx. 25 mph
(Canada: 30 km/h). A signal sounds and the message
“DTR OFF” appears for 5 seconds in the multifunction
display.
Wa r n i n g !
A continuous warning sounds and the distance
warning lamp in the speedometer dial is
illuminated if the Distronic system calculates that
the distance to the vehicle ahead and your vehicle’s
current speed indicate that Distronic will not be
capable of slowing the vehicle sufficiently to
maintain the preset following distance, which
creates a danger of a collision.Immediately brake the vehicle to increase the
distance to the vehicle in front of you. The warning
sound is intended as a final caution that you have
not interceded with your own braking inputs to
avoid a potentially dangerous situation. Do not wait
for the operation of the warning signal to intercede
with your own braking as that will result in
potentially dangerous emergency braking which
will not always result an impact being avoided.Tailgating increases the risk of an accident.
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262 Driving systems
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Traveling through turns or bends in the roadway may
result in Distronic detecting a moving vehicle traveling
in front but not in your lane of travel, causing your
vehicle to brake late or unexpectedly. You must be
prepared to intercede with accelerator or brake
application as necessary.The Distronic system’s detection zone is relatively
narrow at the start and becomes broader as it senses
further from the vehicle. Thus, Distronic may not
recognize another vehicle coming into your path close
to the front of your vehicle. You must be prepared to
intercede with braking or steering as necessary.
A vehicle not traveling directly in front of you could
cause detection problems, the actual distance to that
vehicle really being much shorter.
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263 Driving systems
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data Instruments
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cluster displayPractical hints Car care Index A vehicle changing lanes at close range is only
recognized when entering the area scanned by
Distronic. You must apply the service brakes to gain
sufficient distance to the vehicle ahead.A narrow vehicle (e.g. a motorcycle) is only recognized
when entering the area scanned by Distronic. You must
apply the service brakes to gain sufficient distance to
the vehicle ahead.
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264 Driving systems
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Distance notification function
Even if Distronic is deactivated, the distance to the
vehicle ahead continues to be measured, see page 266
for multifunction display.
The Distronic lamp in the speedometer dial illuminates
to advise the driver of a situation which under normal
braking conditions and dry surfaces should have been
addressed by the driver.
The distance notification function can be activated
separately, see page 265. It operates when driving at
speeds above approx. 25 mph (Canada: 30 km/h).
When recognizing a stationary obstacle or a slower
vehicle moving in the vehicle’s path and the danger of a
collision exists, the distance warning lamp in the
speedometer dial lights up and simultaneously a
continuous warning sounds.
Note:
Model CL 55 AMG only:
Distance notification function is deactivated if the
vehicle speed exceeds approximately 160 mph
(260 km/h).Important!
With the Distronic switched off, only the distance
notification function operates, meaning the vehicle does
not slow down.
Important!
Complex driving situations are not always fully
recognized by Distronic, which could result in wrong or
missing distance warnings.
See page 261 for additional driving hints.
Wa r n i n g !
If the distance warning lamp in the speedometer
dial lights up while driving and a continuous
warning sounds, immediate attention on the part of
the driver is required.As required by the traffic situation, apply the
service brakes and navigate around a possible
obstacle. However, do not drive by relying on the
distance notification function as that will result in
an emergency braking application which,
especially depending on road surface conditions
and driver reaction, will not always be able to avoid
a collision.
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268 Driving systems
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Brake assist system (BAS)
The BAS is designed to maximize the vehicle’s braking
capability during emergency braking maneuvers by
having maximum power boost applied to the brakes
more quickly in emergency braking conditions than
might otherwise be afforded solely by the driver’s
braking style. This can help reduce braking distances
over what ordinary driving and braking style might do.
The BAS complements the antilock brake system (ABS).Applying the brakes very quickly results in maximum
BA S a ssistance.
To receive the benefit of the system you must apply
continuous full braking power during the stopping
sequence. Do not reduce brake pedal pressure.
Once the brake pedal is released, the BAS is deactivated.
If the BAS warning message is displayed, a malfunction
has been detected in the system. The brake system
functions in the usual manner, but without BAS.
With the ABS malfunctioning, the BAS is also switched
off.
If a BAS warning message is displayed, have the BAS
checked at your authorized Mercedes-Benz Center as
soon as possible.
Wa r n i n g !
BAS cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase
braking efficiency beyond that afforded by the
condition of the vehicle brakes and tires or the
traction afforded. The BAS cannot prevent
accidents, including those resulting from excessive
speed in turns, following another vehicle too
closely, or aquaplaning. Only a safe, attentive, and
skillful driver can prevent accidents. The
capabilities of a BAS equipped vehicle must never
be exploited in a reckless or dangerous manner
which could jeopardize the user’s safety or the
safety of others.
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269 Driving systems
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data Instruments
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cluster displayPractical hints Car care Index Antilock brake system (ABS)
Important!
The ABS improves steering control of the vehicle during
hard braking maneuvers.
The ABS prevents the wheels from locking up above a
vehicle speed of approximately 5 mph (8 km/h)
independent of road surface conditions.At the instant one of the wheels is about to lock up, a
slight pulsation can be felt in the brake pedal,
indicating that the ABS is in the regulating mode. Keep
firm and steady pressure on the brake pedal while
experiencing the pulsation.
Continuous steady brake pedal pressure results in
applying the advantages of the ABS, namely braking
power and ability to steer the vehicle.
In the case of an emergency brake maneuver keep
continuous full pressure on the brake pedal. In this
manner only can the ABS be most effective.
On slippery road surfaces, the ABS will respond even
with light brake pedal pressure because of the
increased likelihood of locking wheels. The pulsating
brake pedal can be an indication of hazardous road
conditions and functions as a reminder to take extra
care while driving.
Wa r n i n g !
Do not pump the brake pedal, rather use firm,
steady brake pedal pressure. Pumping the brake
pedal defeats the purpose for ABS and significantly
reduces braking effectiveness.
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270 Driving systems
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ABS control
The ABS malfunction indicator lamp- in the
instrument cluster comes on with the electronic key in
starter switch position 2 and should go out with the
engine running.
When the ABS malfunction indicator lamp in the
instrument cluster comes on while the engine is
running, it indicates that the ABS has detected a
malfunction and has switched off. In this case, the brake
system functions in the usual manner, but without
antilock assistance.
For ABS malfunction indicator lamp, see page 294.
With the ABS malfunctioning, the BAS and ESP are also
switched off. Both malfunction indicator lamps come on
with the engine running.
If the charging voltage falls below 10 volts, the
malfunction indicator lamp comes on and the ABS is
switched off. When the voltage is above this value again,
the malfunction indicator lamp should go out and the
ABS is operational.If the ABS malfunction indicator lamp stays illuminated,
have the system checked at your authorized
Mercedes-Benz Center as soon as possible.
Note:
To alert following vehicles to slippery road conditions
you discover, operate your hazard warning flashers as
appropriate.
Wa r n i n g !
ABS cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase
braking or steering efficiency beyond that afforded
by the condition of the vehicle brakes and tires or
the traction afforded. The ABS cannot prevent
accidents, including those resulting from excessive
speed in turns, following another vehicle too
closely, or aquaplaning. Only a safe, attentive, and
skillful driver can prevent accidents. The
capabilities of a ABS equipped vehicle must never
be exploited in a reckless or dangerous manner
which could jeopardize the user’s safety or the
safety of others.
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271 Driving systems
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data Instruments
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cluster displayPractical hints Car care Index Electronic stability program (ESP)
The ESP enhances directional control and reduces
driving wheel spin of the vehicle under various driving
conditions.
Over/understeering of the vehicle is counteracted by
applying brakes to the appropriate wheel to create a
countervailing vehicle movement. Engine torque is also
limited. The ESP warning lamp, located in the
speedometer dial, starts to flash when ESP is in
operation.Important!
If the ESP warning lampv flashes:
•During take-off apply as little throttle as possible.
•While driving ease up on the accelerator.
•Adapt your speed and driving to the prevailing road
conditions.
•Do not switch off the ESP.
Caution!
If the vehicle is towed with the front axle raised (see
page 351, towing the vehicle), the engine must be shut
off (electronic key in starter switch position 0 or 1).
Otherwise, the ESP will immediately be engaged and
will apply the rear wheel brakes.
Wa r n i n g !
ESP cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase the
traction afforded. The ESP cannot prevent
accidents, including those resulting from excessive
speed in turns, or aquaplaning. Only a safe,
attentive, and skillful driver can prevent accidents.
The capabilities of an ESP equipped vehicle must
never be exploited in a reckless or dangerous
manner which could jeopardize the user’s safety or
the safety of others.
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