2012 MERCEDES-BENZ CL-Class warning lights

Ultrasonic sources such as an automatic
car wash, the compressed-air brakes on a
truck or a pneumatic drill could cause
PARKTRONIC to malfunction.
PARKTRONIC may not function correctly on
uneven terrain.
Minimum distanceCenterApproximately 8 in
(approximately 20 cm)CornersApproximately 8 in
(approximately 20 cm)
If there is an obstacle within this range, the
relevant warning displays light up and a
warning tone sounds. If the distance falls
below the minimum, the distance may no
longer be shown.
Warning displays
The warning displays show the distance
between the sensors and the obstacle. The
warning display for the front area is in the
instrument cluster. The warning display for
the rear area is located on the headliner in the
rear compartment.
Warning display for the front area
:Segments on the left-hand side of the
vehicle;Segments on the right-hand side of the
vehicle=Segments showing operational readiness
The warning display for each side of the
vehicle is divided into five yellow and two red
segments. PARKTRONIC is operational if
yellow segments showing operational
readiness = light up.
The selected transmission position
determines which warning display is active
when the engine is running.Transmission
positionWarning displayDFront area activatedRRear and front areas
activatedNIf the electric parking
brake is engaged: no
areas are activated
If the electric parking
brake is released:
rear and front areas
are activatedPNo areas activated
One or more segments light up as the vehicle
approaches an obstacle, depending on the
vehicle's distance from the obstacle.
When the first red segment lights up, you hear
an intermittent warning for about two
seconds. From the second red segment, you
hear a continuous warning. This indicates that
you have now reached the minimum distance.
Deactivating/activating PARKTRONIC
:To deactivate/activate PARKTRONIC;Indicator lamp308Driving systemsDriving and parking

Problems with PARKTRONICProblemPossible causes/consequences and M SolutionsOnly the red segments
in the PARKTRONIC
warning displays are lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is
deactivated after
approximately
20 seconds, and the
indicator lamp in the
PARKTRONIC button
lights up.PARKTRONIC has malfunctioned and has switched off.XIf problems persist, have PARKTRONIC checked at a qualified
specialist workshop.Only the red segments
in the PARKTRONIC
warning displays are lit.
PARKTRONIC is
deactivated after
approximately 20
seconds.The PARKTRONIC sensors are dirty or there is interference.XClean the PARKTRONIC sensors ( Y page 418).XSwitch the ignition back on.The problem may be caused by an external source of radio or
ultrasound waves.XSee if PARKTRONIC functions in a different location.Parking Guidance
Important safety notes
Parking Guidance is an electronic parking aid
with ultrasound. Ultrasound is used to
measure the road on both sides of the vehicle.
A suitable parking space is indicated by the
parking symbol. You receive steering
instructions when parking. You may also use
PARKTRONIC ( Y page 306).
GWARNING
Parking Guidance is merely an aid and may
display parking spaces that are not suitable
for parking, for example:
R no-parking areas
R parking spaces with unsuitable surfaces
(road surface)
R driveways
R entrances and exits
Parking Guidance detects and measures
potential parking spaces while driving past.
Changes to the parking space after this point
are not taken into account, for example if the
vehicle in front of or behind the parking space
changes position or objects in the parking
space are moved.
Even when using Parking Guidance, you are
still responsible for driving carefully. If you
rely on Parking Guidance alone, you could
cause an accident and injure yourself and
others.
Safety always remains your responsibility and
you must continue paying careful attention to
your immediate surroundings when parking
and maneuvering.310Driving systemsDriving and parking

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

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

Display messagesPossible causes/consequences and M SolutionsThe yellow F (USA only)/ ! (Canada only) warning lamp
lights up. The red F (USA only)/ ! (Canada only) indicator
lamp flashes for approximately 10 seconds after the electric
parking brake has been applied or released. It then goes out or
remains lit.
The electric parking brake is malfunctioning, e.g. because of
overvoltage or undervoltage.XPull away carefully.XVisit a qualified specialist workshop.
If there is overvoltage or undervoltage:
XRemove the cause for the overvoltage or undervoltage, e.g. by
charging the battery or restarting the engine.XSwitch the ignition off and on, and then engage or release the
electric parking brake.
If this does not release the electric parking brake:
XDo not drive on.XConsult a qualified specialist workshop.The yellow F (USA only)/ ! (Canada only) warning lamp
lights up. The red F (USA only)/ ! (Canada only) indicator
lamp flashes for approximately 10 seconds after the electric
parking brake has been applied or released. It then goes out or
remains lit.
The electric parking brake has overheated.XAllow the vehicle to cool down. Do not engage or release the
electric parking brake during this time.XUse the folding wheel chock (Y page 426) from the vehicle tool
kit to secure the vehicle against rolling away.XWhen the vehicle has cooled down: switch the ignition off and
on again, then engage or release the electric parking brake.352Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M SolutionsF (USA
only) ! (Canada
only)
Parking Brake
InoperativeThe yellow F (USA only)/ ! (Canada only) warning lamp
lights up. The red F (USA only)/ ! (Canada only) indicator
lamp flashes for approximately 10 seconds after the electric
parking brake has been applied or released. It then goes out or
remains lit.
The electric parking brake is malfunctioning.XSwitch the ignition off and on, and then engage the electric
parking brake.
If it is not possible to engage the electric parking brake:
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.F (USA
only) ! (Canada
only)
Turn On the
Ignition to
Release the
Parking BrakeThe red F (USA only)/ ! (Canada only) indicator lamp lights
up.
You attempted to release the electric parking brake while the
ignition was switched off.XSmartKey: turn the SmartKey to position 1 in the ignition lock.XKEYLESS-GO: switch on the ignition.$(USA
only) J (Canada
only)
Service See Oper.
ManualThere is a malfunction in the system. The brake system continues
to operate normally.XDrive on carefully.XVisit a qualified specialist workshop.$ (USA
only) J (Canada
only)
Check Brake Fluid
LevelGRisk of accident
There is not enough brake fluid in the brake fluid reservoir.
Additionally, the red $ (USA only)/ J (Canada only)
warning lamp lights up in the instrument cluster and a warning
tone sounds.
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.XEngage the electric parking brake.XConsult a qualified specialist workshop.XDo not add brake fluid. This will not rectify the malfunction.Display messages353On-board computer and displaysZ

Display messagesPossible causes/consequences and M SolutionsPRE-SAFE
Functions
Currently Limited
See Operator's
ManualGRisk of accident
PRE-SAFE ®
Brake is temporarily inoperative if:
R the DISTRONIC PLUS cover in the radiator grill is dirty.
R the sensors in the bumpers are dirty.
R its function is impaired due to heavy rain or snow.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio
stations or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
PRE-SAFE ®
Brake is operational again and the display message
disappears if:
R the dirt (e.g. slush) drops away while the vehicle is in motion.
R the system detects that the sensors are fully available again.
R the system is within the operating temperature range.
If the display message continues to be displayed:
XClean the DISTRONIC PLUS cover in the radiator grill
( Y page 418).XClean the bumpers ( Y page 418).XRestart the engine.XWait until the battery is sufficiently charged.PRE-SAFE
Function Limited
See Oper. ManualGRisk of accident
PRE-SAFE ®
Brake is defective. BAS PLUS or the distance warning
signal may also have failed.
XVisit a qualified specialist workshop.6
SRS Malfunction
Service RequiredGRisk of injury
There is a malfunction in the SRS (Supplemental Restraint
System). The 6 warning lamp also lights up in the instrument
cluster.
XVisit a qualified specialist workshop.Display messages355On-board computer and displaysZ