2008 MERCEDES-BENZ CL-Class brake sensor

68 Safety and SecurityDriving safety systemsBAS Plus*
The Brake Assist System Plus (BAS Plus)
operates in emergency braking situations
and uses radar sensors* to assess the traf-
fic situation. BAS Plus assists you in brak-
ing at speeds above approximately 20 mph
(30 km/h).
When travelling in Canada in a vehicle not
registered in Canada, you must switch off
the radar sensor system* (
page 302).
Canadian law does not permit the use of
the radar sensor system* (
page 302) for
vehicles from outside of Canada. When you
switch off the radar sensor system*, the
following functions are deactivated:


BAS Plus


DISTRONIC Plus* (
page 443)


Park Assist* (
page 467)


PRE-SAFE
® Brake* (
page 75)BAS Plus detects obstacles that are in your
driving path for a sufficient period of time
to permit the system to recognize these
obstacles. If you approach the detected
obstacle quickly, BAS Plus calculates the
level of brake power boost appropriate for
the circumstance to supply when the driv-
er applies the brakes.
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 automotive radar system
only. Removal, tampering, or altering of the de-
vice will void any warranties, 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 re-
ceived, 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.
Warning!
G
BAS Plus is a convenience system designed
to assist the driver during vehicle operation.
The responsibility for the vehicle speed and
the distance to the vehicle ahead, including
most importantly brake operation to assure
safe stopping distance, always remains with
the driver.
Always pay attention to traffic conditions
even while BAS Plus is switched on. Other-
wise, you may not be able to recognize
dangerous situations until it is too late and
could cause an accident resulting in person-
al or fatal injury to you or others.

69 Safety and Security
Driving safety systems
When you step quickly on the brake pedal
in an emergency braking situation,
BAS Plus automatically regulates the
brake power boost to a level that is suit-
able for the traffic situation.
If BAS Plus requires a particularly high
brake power boost, PRE-SAFE
® is activat-
ed at the same time.

Keep constant pressure on the brake
pedal until the emergency braking situ-
ation is over.
During this process, ABS prevents the
wheels from locking up.The brakes will resume normal operation
after


the brake pedal is released


no obstacles are detected in your path


the system no longer senses a risk of a
collision
BAS Plus is deactivated.
BAS Plus can react to stationary obstacles
such as standing or parked vehicles at
road speeds of up to approximately
40 mph (70 km/h).
BAS Plus can only assist you when the
radar sensors are switched on and func-
tional. You can check whether the sensors
are active by switching on DISTRONIC
Plus* (
page 443) or using the “Radar
Sensors” menu (
page 302) in the instru-
ment cluster control system.
Warning!
G
BAS Plus will only respond with brake assis-
tance if it has clearly detected an object. De-
tection can be impeded by

dirty or covered sensors


snowfall or heavy rain


disturbance from other radar sources


strong radar reflection such as in park-
ing garages
BAS Plus uses radar signals that are not re-
flected well by narrow objects and absorp-
tive materials. For this reason BAS Plus will
not react to


persons and animals


approaching traffic or cross-traffic
BAS Plus may not detect narrow vehicles
driving in front of you, such as motorcycles
and vehicles driving offset from your vehicle
center.

70 Safety and SecurityDriving safety systemsAfter a hard collision or damage to the
front of the vehicle from an accident, have
the adjustment and operation of the radar
sensors checked by an authorized
Mercedes-Benz Center.
If BAS Plus is not available due to a radar
sensor malfunction, the braking system
will continue to function normally with full
brake boost and full standard BAS
function.
EBP
The Electronic Brake Proportioning (EBP)
enhances braking effectiveness by allow-
ing the rear brakes to supply a greater pro-
portion of the braking effort in straight line
braking without a loss of vehicle stability.
ESP
®
The Electronic Stability Program (ESP
®) is
operational as soon as the engine is run-
ning and monitors the vehicle’s traction
(force of adhesive friction between the
tires and the road surface) and handling.
The ESP
® recognizes when a wheel is spin-
ning or if the vehicle starts to skid. By ap-
plying brakes to the appropriate wheel and
by limiting the engine output, the ESP
®
works to stabilize the vehicle. The ESP® is
especially useful while driving off and on
wet or slippery road surfaces. The ESP®
also stabilizes the vehicle during braking
and steering maneuvers.
The ESP
® warning lamp v in the instru-
ment cluster flashes when the ESP
® is en-
gaged.
The ESP
® warning lamp v in the instru-
ment cluster comes on when you switch on
the ignition (
page 365). It goes out when
the engine is running.
Warning!
G
When the EBP is malfunctioning, the ABS,
BAS, BAS Plus* and ESP
® are also switched
off.
If the EBP is malfunctioning, the brake sys-
tem will still function with full brake boost.
However, the rear wheels could lock up dur-
ing emergency braking situations, for exam-
ple. You could lose control of the vehicle and
cause an accident. Adapt your driving style
to the changed driving characteristics.

75 Safety and Security
Driving safety systems
PRE-SAFE
® Brake* (vehicles with
DISTRONIC Plus* only)
PRE-SAFE
® Brake* can assist you in mini-
mizing the risk of a rear-end collision with
a vehicle in front of you and in reducing the
severity of an accident. At speeds over ap-
proximately 20 mph (30 km/h), it will


warn you of a possible collision


automatically begin to brake the vehi-
cle lightly in a speed range of up to
112 mph (180 km/h)


activate preventative occupant safety
measures (PRE-SAFE
®) (page 56)PRE-SAFE
® Brake will only assist you by
automatically initiating braking if the driver
and front passenger have their seat belts
fastened.
Using the radar sensors, PRE-SAFE
® Brake
detects obstacles that are in your driving
path for a sufficient period of time for the
system to recognize it. If you approach a
vehicle and PRE-SAFE
® Brake has estab-
lished that the distance to the vehicle
ahead at your current speed is so close
that PRE-SAFE
® Brake will not be capable
of slowing the vehicle sufficiently, the sys-
tem will initially warn you visually and
acoustically.When travelling in Canada in a vehicle not
registered in Canada, you must switch off
the radar sensor system* (
page 302).
Canadian law does not permit the use of
the radar sensor system* (
page 302) for
vehicles from outside of Canada. When you
switch off the radar sensor system*, the
following functions are deactivated:


BAS Plus* (
page 68)


DISTRONIC Plus* (
page 443)


Park Assist* (
page 467)


PRE-SAFE
® Brake
Warning!
G
PRE-SAFE
® Brake is a convenience system
designed to assist the driver during vehicle
operation. The responsibility for the vehicle
speed and the distance to the vehicle ahead,
including most importantly brake operation
to assure safe stopping distance, always re-
mains with the driver.
Always pay attention to traffic conditions
even while PRE-SAFE
® Brake is switched on.
Otherwise, you may not be able to recognize
dangerous situations until it is too late and
could cause an accident resulting in person-
al or fatal injury to you or others.
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 automotive radar system
only. Removal, tampering, or altering of the de-
vice will void any warranties, 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.

76 Safety and SecurityDriving safety systems
When the distance to the forward vehicle is
too small, the distance warning lampl
comes on in the instrument cluster. If you
approach the forward vehicle very quickly,
you will hear a warning tone.
If you do not apply the brakes yourself or
maneuver around a sensed obstacle, the
vehicle will automatically initiate light
braking. PRE-SAFE
® (page 56) is activat-
ed when the distance to the vehicle ahead
at your current speed is so close that
PRE-SAFE
® Brake will not be capable of
slowing the vehicle sufficiently.
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 re-
ceived, 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.
Warning!
G
PRE-SAFE
® Brake will only respond with
brake assistance if it has clearly detected an
object. Detection can be impeded by


dirty or covered sensors


snowfall or heavy rain


disturbance from other radar sources


strong radar reflection such as in park-
ing garages
PRE-SAFE
® Brake uses radar signals that
are not reflected well by narrow objects and
absorptive materials. For this reason BAS
Plus will not react to


persons and animals


approaching traffic or cross-traffic
PRE-SAFE
® Brake may not detect narrow ve-
hicles driving in front of you, such as motor-
cycles and vehicles driving offset from your
vehicle center.

78 Safety and SecurityDriving safety systemsPRE-SAFE
® Brake can react to stationary
obstacles such as standing or parked vehi-
c le s a t roa d s pe eds of up to ap proxim a tel y
40 mph (70 km/h).

Activating and deactivating: Activate
or deactivate PRE-SAFE
® Brake using
the instrument cluster control system
(
page 298).
After the function has been activated,
indicator : appears on the
left-hand side of the multifunction dis-
play.PRE-SAFE
® Brake does not always clearly
interpret complex traffic situations. If a vi-
sual and/or acoustic warning is issued in
an uncritical driving situation, or if the ve-
hicle brakes lightly, you can interrupt the
PRE-SAFE® Brake maneuver by


pressing down all the way on the accel-
erator or using kickdown


releasing the brake pedal
The PRE-SAFE
® Brake maneuver is termi-
nated immediately when


you avoid the obstacle by evasive
steering


you drive less than 9 mph (15 km/h)


an obstacle can no longer be identified
ahead of you


the system no longer senses the risk of
a collisionAfter a hard collision or damage to the
front of the vehicle from an accident, have
the settings and operation of the radar
sensors checked by an authorized
Mercedes-Benz Center.
Warning!
G
If you do not receive visual or acoustic warn-
ing signals, PRE-SAFE
® Brake has either not
recognized the collision risk, has been deac-
tivated or is malfunctioning. Apply the
brakes yourself to avoid a collision.
i
PRE-SAFE
® Brake will remain passive while
DISTRONIC Plus* is switched on (
page 443).

285 Control systems
Instrument cluster control system
Telephone* (
page 294)
Assistance* (
page 298)
Service (
page 299)
Settings (
page 301)
Commands/submenusDialing a number from the
phone book
Displaying the distance graphic*,
DISTRONIC Plus*
Calling up vehicle malfunction,
warning and system status
messages stored in memory
Setting daytime running lamp
mode (USA only)
Redialing
Activating/deactivating
PRE-SAFE
® Brake* (vehicles with
DISTRONIC Plus* only)
Checking tire inflation pres-
sure
Switching additional
speedometer on or off
Answering a call
Switching on or off Rear View
Camera* automatically
Calling up maintenance service
display
Switching on or off radar
sensors*
Ending a call or rejecting an
incoming call
Switching on or off Blind Spot
Assist*
Checking engine oil level
(CL 600)

302 Control systemsInstrument cluster control systemSwitching on or off radar sensors*
If your vehicle is equipped with DISTRONIC
Plus*, BAS Plus*, or Park Assist* it is
equipped with a radar sensor system
which you can switch on and off.
When travelling in Canada in a vehicle not
registered in Canada, you must switch off
the radar sensor system. Canadian law
does not permit the use of the radar sensor
system for vehicles from outside of Cana-
da. When you switch off the radar sensor
system, the following functions are
deactivated:

BAS Plus* (
page 68)


PRE-SAFE
® Brake* (
page 75)


DISTRONIC Plus* (
page 443)


Park Assist* (
page 467)


Advanced Parking Guidance*
(page 471)


Blind Spot Assist* (
page 485)

Press ( or & to select the “Set-
tings” menu.

Press % or $ to select the “Ra-
dar Sensors” function.

Press #.

Press # again if you would like to
change the current status.
Depending on the previous status, the
radar sensors will be switched on or
off.
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 automotive radar system
only. Removal, tampering, or altering of the de-
vice will void any warranties, 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 re-
ceived, 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.
i
The selected status of the radar sensors re-
mains stored in memory even if the engine is
turned off and restarted.
i
The following message appears in the multi-
function display if the radar sensors are
switched off and you attempt to activate
DISTRONIC Plus*, Park Assist* or PRE-SAFE
®
Brake*:
“Radar Sensors
(See Oper. Manual)
Disabled”