2012 MERCEDES-BENZ CL-Class warning light

Due to the nature of the system:
R warnings may be issued in error when
driving close to crash barriers or similar
solid lane borders.
R warnings may be interrupted when driving
alongside long vehicles, such as trucks, for
a prolonged time.
Two Active Blind Spot Assist radar sensors
are integrated into the front and rear bumpers
respectively. An additional radar sensor is
located behind the cover in the radiator grill.
Make sure that the sensor areas on the
bumpers and the sensor cover in the radiator
grill are free of dirt, ice and slush. The rear
sensors must not be covered, for example by
cycle racks or overhanging cargo. Following
a severe impact or in the event of damage to
the bumpers, have the function of the radar
sensors checked at a qualified specialist
workshop. Blind Spot Assist may otherwise
not work properly.
Indicator and warning display:Yellow indicator lamp/red warning lamp
When Active Blind Spot Assist is activated,
indicator lamp : lights up yellow in the
exterior mirrors up to a vehicle speed of
20 mph (30 km/h). When the vehicle speed
exceeds 20 mph (30 km/h), the indicator
lamp goes out and Active Blind Spot Assist is
ready for use.
When your speed exceeds approximately
20 mph (30 km/h), warning lamp : lights up
red on the corresponding side whenever a
vehicle is detected in the blind spot
monitoring range. This warning is always
given when a vehicle enters the blind spot
monitoring range from behind or from the
side. When you are passing another vehicle,
the warning is emitted only if the difference
in speed is less than 7 mph (12 km/h).
The yellow indicator lamp goes out if reverse
gear is engaged. In this event, Active Blind
Spot Assist is no longer active.
The brightness of the indicator/warning
lamps is adjusted automatically according to
the ambient light.GWARNING
Active Blind Spot Assist is not active at speeds
lower than 20 mph (30 km/h). The indicator
lamps in the exterior mirrors are yellow.
Vehicles in the monitoring range are then not
indicated.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognize dangers in time, cause an accident
and injure yourself and others.
Visual and audible collision warnings
If you switch on the appropriate turn signals
and a vehicle is detected in the side
monitoring range, you will receive a visual and
acoustic collision warning. You will hear a
double warning tone and red warning
lamp : flashes. If the turn signal remains on,
vehicles detected are indicated by the
flashing of red warning lamp :. There are no
further warning tones.
Course-correcting brake application
If Active Blind Spot Assist detects a risk of a
lateral collision in the monitoring range, a
course-correcting brake application is carried
out. This is meant to assist you in avoiding a
collision.
The course-correcting brake application is
available in the range between 20 mph
(30 km/h) and 120 mph (200 km/h).
If a course-correcting brake application
occurs, red warning lamp : flashes in the
Driving systems323Driving and parkingZ

exterior mirror and the following is shown in
the multifunction display, for example:GWARNING
Active Blind Spot Assist is only an aid
designed to assist driving. It is not a substitute
for attentive driving. In some cases, the
course-correcting brake application is not
sufficient to avoid a collision. In such a case,
you must steer, brake or accelerate.
In very rare cases, the system may
erroneously detect a danger of collision in the
area of crash barriers or similar lane borders
and apply the brakes. Active Blind Spot Assist
does not detect all traffic situations and road
users. Always make sure that there is
sufficient distance on the side for other traffic
or obstacles. An inappropriate brake
application may be interrupted at any time if
you steer slightly in the opposite direction or
accelerate.
You are responsible for driving at appropriate
speeds, braking in good time, and steering
correctly. Always adapt your driving style to
suit the prevailing road and weather
conditions. Always pay attention to traffic
conditions and your surroundings. Otherwise,
you may fail to recognize dangers in time,
cause an accident and injure yourself and
others.
There will be either no or only a weak course-
correcting brake application if:
R there are vehicles or obstacles, e.g. crash
barriers, located on both sides of your
vehicle.
R a vehicle approaches you too closely at the
side.
R you have adopted a sporty driving style with
high cornering speeds.
R you clearly brake or accelerate.
R a driving safety system intervenes, e.g.
ESP ®
or PRE-SAFE ®
Brake.
R ESP ®
is switched off.
R a loss of tire pressure or a defective tire is
detected.
Switching on Active Blind Spot AssistXMake sure that the radar sensor system
( Y page 344) and Active Blind Spot Assist
( Y page 343) are activated in the on-board
computer.XTurn the SmartKey to position 2 in the
ignition lock.
Warning lamps : light up red in the
exterior mirrors for approximately 1.5
seconds and then turn yellow.
Active Lane Keeping Assist
Important safety notes
Active Lane Keeping Assist monitors the area
in front of your vehicle by means of a camera
at the top of the windshield. Active Lane
Keeping Assist detects lane markings on the
road and warns you before you leave your
lane unintentionally. If you do not react to the
warning, a lane-correcting application of the
brakes can bring the vehicle back into the
original lane.
:Active Lane Keeping Assist camera
If you have selected the Display Unit
Speed-/Odometer (Y page 344) function in
the on-board computer and select km as the
unit of measurement, Active Lane Keeping
324Driving systemsDriving and parking

application also slightly reduces vehicle
speed.
If a lane-correcting brake application occurs,
the following, for example, appears in the
multifunction display:
i A further lane-correcting brake
application can only occur after your
vehicle has returned to the original lane.
GWARNING
Active Lane Keeping Assist does not keep
your vehicle in its lane. It is only an aid
designed to assist driving. It is not a substitute
for attentive driving. In some cases, the lane-
correcting brake application is not sufficient
to bring your vehicle back to the original lane.
In such cases, you must steer the vehicle
yourself to ensure that it does not leave the
lane.
Active Lane Keeping Assist does not detect
road and traffic conditions. Always make sure
that there is sufficient distance to the side for
other traffic or obstacles. In rare cases,
unclear markings or particular structures on
the roadway can be recognized as solid lane
markings. An inappropriate brake application,
e.g. after intentionally driving over a solid lane
marking, may be interrupted at any time by
steering slightly in the opposite direction.
Active Lane Keeping Assist cannot take
weather conditions into account.
You are responsible for the driving at
appropriate speeds, braking in good time, and
steering correctly. Always adapt your driving
style to suit the prevailing road and weather
conditions. Always pay attention to traffic
conditions and your surroundings. Otherwise,
you may fail to recognize dangers in time,
cause an accident and injure yourself and
others.
No lane-correcting brake application occurs
if:
R you clearly and actively steer, brake or
accelerate.
R you cut the corner on a sharp bend.
R you switch on the turn signals.
R a driving safety system intervenes, e.g.
ESP ®
, PRE-SAFE ®
Brake or Active Blind
Spot Assist.
R you have adopted a sporty driving style with
high cornering speeds or high rates of
acceleration.
R ESP ®
is switched off.
R the transmission is not in position D.
R a loss of tire pressure or a defective tire has
been detected and displayed.
Active Lane Keeping Assist does not detect
traffic situations or road users. An
inappropriate brake application may be
interrupted at any time if you:
R steer slightly in the opposite direction.
R use a turn signal.
R clearly brake or accelerate.
A lane-correcting brake application is
interrupted automatically if:
R a driving safety system intervenes, e.g.
ESP ®
, PRE-SAFE ®
Brake or Active Blind
Spot Assist.
R lane markings can no longer be recognized.
Switching on Active Lane Keeping Assist326Driving systemsDriving and parking

Safety systemsDisplay messagesPossible causes/consequences and M Solutions!÷
Currently
Unavailable See
Oper. ManualGRisk of accident
ABS (Anti-lock Braking System), ESP ®
(Electronic Stability
Program), BAS (Brake Assist), PRE-SAFE ®
, the HOLD function and
hill start assist are temporarily unavailable.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster.
The self-diagnosis function might not be complete, for example.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XCarefully drive a suitable distance making slight steering
movements at a speed above 12 mph (20 km/h).
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.GRisk of accident
ABS, ESP ®
, BAS, PRE-SAFE ®
, the HOLD function and hill start
assist are temporarily unavailable.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster.
For example, the on-board voltage may be insufficient.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XDrive on carefully.
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.Display messages347On-board computer and displaysZ

Display messagesPossible causes/consequences and M Solutions!÷
Inoperative See
Oper. ManualGRisk of accident
ABS, ESP ®
, BAS, PRE-SAFE ®
, the HOLD function and hill start
assist are unavailable due to a malfunction.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
The $ (USA only)/ J (Canada only), ÷, å
and ! warning lamps in the instrument cluster also light up.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
ATTENTION ASSIST is deactivated.
XDrive on carefully.XVisit a qualified specialist workshop immediately.÷
Currently
Unavailable See
Oper. ManualGRisk of accident
ESP ®
, BAS, PRE-SAFE ®
, the HOLD function and hill start assist are
temporarily unavailable.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷ and å warning lamps light up in the
instrument cluster.
The self-diagnosis function might not be complete, for example.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above.
XCarefully drive a suitable distance making slight steering
movements at a speed above 12 mph (20 km/h).
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.GRisk of accident
If the display message is shown and the ÷ warning lamp flashes
at the same time, the Electronic Traction System is deactivated.
Otherwise, the brakes on the drive wheels could overheat.
XLet the brakes cool down until the display message disappears
and the ÷ warning lamp goes out.
The Electronic Traction System is activated again.348Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M Solutions÷
Inoperative See
Oper. ManualGRisk of accident
ESP ®
, BAS, PRE-SAFE ®
, the HOLD function and hill start assist are
unavailable due to a malfunction.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷ and å warning lamps light up in the
instrument cluster.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above.
XDrive on carefully.XVisit a qualified specialist workshop.å
System InoperativeGRisk of accident
ESP ®
, BAS, PRE-SAFE ®
, the HOLD function and hill start assist are
unavailable due to a malfunction. BAS PLUS and PRE-SAFE ®
Brake
may also have failed. In addition, the ÷ and å warning
lamps light up in the instrument cluster.
ATTENTION ASSIST is deactivated.
XDrive on carefully.XVisit a qualified specialist workshop.T !
÷
Inoperative See
Oper. Manual GRisk of accident
EBD (electronic brake force distribution), ABS, ESP ®
, BAS, PRE-
SAFE ®
, the HOLD function and hill start assist are unavailable due
to a malfunction.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster and a warning tone sounds.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XDrive on carefully.XVisit a qualified specialist workshop immediately.#
Check Brake Pad
WearThe brake pads/linings have reached their wear limit.XVisit a qualified specialist workshop.Display messages349On-board computer and displaysZ

Display messagesPossible causes/consequences and M SolutionsF (USA
only) ! (Canada
only)
Please Release
Parking BrakeThe red F (USA only)/ ! (Canada only) indicator lamp
flashes and a warning tone sounds.
You are driving with the electric parking brake applied.XRelease the electric parking brake.
or
XPull away carefully ( Y page 284).The red F (USA only)/ ! (Canada only) indicator lamp
flashes and a warning tone sounds.
You are making an emergency stop using the electric parking
brake ( Y page 284).XAfter the emergency stop: release the electric parking brake
lever.The red F (USA only)/ ! (Canada only) indicator lamp
flashes, the yellow F (USA only)/ ! (Canada only) warning
lamp lights up and a warning tone sounds.
The electric parking brake is malfunctioning and the braking effect
is restricted.
While the vehicle is in motion:XRelease the electric parking brake handle.
While the vehicle is stationary:
XSwitch off the ignition and turn it back on.XRelease the electric parking brake.
If the display message continues to be displayed:
XShift the transmission to P.XUse the folding wheel chock (Y page 426) from the vehicle tool
kit to secure the vehicle against rolling away.XConsult a qualified specialist workshop.350Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M SolutionsF (USA
only) ! (Canada
only)
Parking Brake See
Oper. ManualThe yellow F (USA only)/ ! (Canada only) warning lamp
lights up. Additionally, the red F (USA only)/ ! (Canada
only) indicator lamp may light up.
The electric parking brake is malfunctioning.
To release:XPull the electric parking brake handle.
or
XPull away carefully.XVisit a qualified specialist workshop.
To apply:
XSwitch off the ignition.XPull the electric parking brake lever for at least ten seconds,
until the display message disappears.
If the display message continues to be displayed:
XShift the transmission to P.XUse the folding wheel chock (Y page 426) from the vehicle tool
kit to secure the vehicle against rolling away.XConsult a qualified specialist workshop.The red F (USA only)/ ! (Canada only) indicator lamp lights
up.
The power supply for the electric parking brake was interrupted.XPull the electric parking brake handle.
or
XPull away carefully.
or
XPull the electric parking brake handle until the display message
disappears.The red F (USA only)/ ! (Canada only) indicator lamp
flashes and the yellow F (USA only)/ ! (Canada only)
warning lamp lights up.
The electric parking brake is malfunctioning.XSwitch off the ignition and turn it back on.XEngage or release the electric parking brake.
or
XPull away carefully.XVisit a qualified specialist workshop.Display messages351On-board computer and displaysZ