2015 MERCEDES-BENZ CLS-Class radiator

The warning vibration occurs earlier if:
R you approach the outer lane marking on a
bend.
R the road has very wide lanes, e.g. a high-
way.
R the system recognizes solid lane markings.
The warning vibration occurs later if:
R the road has narrow lanes.
R you cut the corner on a bend. Active Driving Assistance package
General notes The Active Driving Assistance package con-
sists of DISTRONIC PLUS (Y
page 181), Active
Blind Spot Assist (Y page 218) and Active
Lane Keeping Assist (Y page 221).
Active Blind Spot Assist General notes
Active Blind Spot Assist uses a radar sensor
system, pointed toward the rear of the vehi-
cle, to monitor the area to the sides of the
vehicle which the driver is unable to see. A
warning display in the exterior mirrors draws
your attention to vehicles detected in the
monitored area. If you then switch on the cor-
responding turn signal to change lanes, you
will also receive a visual and audible collision
warning. If a risk of lateral collision is detec-
ted, corrective braking may help you avoid a
collision. Before a course-correcting brake
application, Active Blind Spot Assist evalu-
ates the space in the direction of travel and at
the sides of the vehicle. For this, Active Blind
Spot Assist uses the forward-facing radar
sensors.
Active Blind Spot Assist supports you from a
speed of approximately 20 mph (30 km/h).
Important safety notes
Active Blind Spot Assist is only an aid and is
not a substitute for attentive driving. G
WARNING
Active Blind Spot Assist does not react to:
R vehicles overtaken too closely on the side,
placing them in the blind spot area
R vehicles which approach with a large speed
differential and overtake your vehicle
As a result, Active Blind Spot Assist may nei-
ther give warnings nor intervene in such sit-
uations. There is a risk of an accident.
Always observe the traffic conditions care-
fully, and maintain a safe lateral distance.
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 automotiveradar system only. Removing, tampering
with, or altering the device 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 harmful inter-
ference, and
2. This device must accept any interference
received, 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.
Radar sensors
The Active Blind Spot Assist radar sensors are
integrated into the front and rear bumpers
and behind a cover in the radiator trim. Make sure that the bumpers and the cover in the 218
Driving systemsDriving and pa
rking

radiator grill are free of dirt, ice or slush. The
rear sensors must not be covered, for exam-
ple by cycle racks or overhanging cargo. Fol-
lowing a severe impact or in the event of dam- age to the bumpers, have the function of the
radar sensors checked at a qualified special-
ist workshop. Active Blind Spot Assist may
otherwise no longer work properly.
Monitoring area G
WARNING
Active Blind Spot Assist does not detect all
traffic situations and road users. There is a
risk of an accident.
Always make sure that there is sufficient dis-
tance on the side for other traffic or obstacles. The detection of obstacles can be impaired in
the case of:
R there is dirt on the sensors or anything else
covering the sensors
R poor visibility, e.g. due to rain, snow or
spray
Vehicles in the monitoring range are then not indicated or indicated with a delay.
Active Blind Spot Assist may not detect nar-
row vehicles, such as motorcycles or bicy-
cles, or may only detect them too late.
If the lanes are narrow, vehicles driving in the
lane beyond the lane next to your vehicle may be indicated, especially if the vehicles are not
driving in the middle of their lane. This may be the case if there are vehicles at the edge of
their lane.
Due to the nature of the system:
R warnings may be issued in error when driv-
ing close to crash barriers or similar solid
lane borders.
R the warning is canceled when driving for an
extended period next to long vehicles, such
as trucks.
Warning display :
Warning display
Active Blind Spot Assist is not active at
speeds below approximately 20 mph
(30 km/h). Vehicles in the monitoring range
are then not indicated.
When Active Blind Spot Assist is activated,
indicator lamp :in the exterior mirrors lights
up yellow at speeds of up to 20 mph
(30 km/h). At speeds above 20 mph
(30 km/h), the indicator lamp goes out and
Active Blind Spot Assist is operational.
If a vehicle is detected within the blind spot
monitoring range at speeds above 20 mph
(30 km/h), warning lamp :on the corre-
sponding side lights up red. This warning is
always given when a vehicle enters the blind
spot monitoring range from behind or from
the side. When you overtake a vehicle, the
warning only occurs if the difference in speed
is less than 7 mph (12 km/h). Driving systems
219Driving and parking Z

Switching on Active Blind Spot Assist
X Make sure that Active Blind Spot Assist is
activated in the on-board computer
(Y page 237).
X Turn the SmartKey to position 2in the igni-
tion lock.
Warning lamps :in the exterior mirrors
light up red for approximately 1.5 seconds
and then turn yellow.
Active Lane Keeping Assist General notes
Active Lane Keeping Assist monitors the area
in front of your vehicle by means of multi-
function camera :at the top of the wind-
shield. Various different areas to the front,
rear and side of your vehicle are also moni-
tored with the aid of the radar sensor system. Active Lane Keeping Assist detects lane
markings on the road and can warn you
before you leave your lane unintentionally. If
you do not react to the warning, a lane-cor-
recting application of the brakes can bring the
vehicle back into the original lane.
This function is available in the range between
40 mph and 120 mph (60 km/h and
200 km/h).
For Active Lane Keeping Assist to assist you
when driving, the radar sensor system must
be operational
Important safety notes
If you fail to adapt your driving style, Active
Lane Keeping Assist can neither reduce the
risk of accident nor override the laws of phys- ics. Active Lane Keeping Assist cannot take
account of road and weather conditions. It
may not recognize traffic situations. Active
Lane Keeping Assist is only an aid. You are
responsible for the distance to the vehicle in
front, for vehicle speed, for braking in good
time and for staying in your lane.
Active Lane Keeping Assist cannot continu-
ously keep your vehicle in its lane. G
WARNING
Active Lane Keeping Assist cannot always
clearly detect lane markings.
In such cases, Active Lane Keeping Assist
can:
R give an unnecessary warning and then
make a course-correcting brake application
to the vehicle
R not give a warning or intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and keep within the lane, especially
if Active Lane Keeping Assist alerts you. Ter-
minate the intervention in a non-critical driv-
ing situation.
The system may be impaired or may not func-
tion if:
R there is poor visibility, e.g. due to insuffi-
cient illumination of the road, or due to
snow, rain, fog or spray
R there is glare, e.g. from oncoming traffic,
the sun or reflections (e.g. when the road
surface is wet)
R the windshield is dirty, fogged up, damaged
or covered, for instance by a sticker, in the
vicinity of the camera
R the radar sensors in the front or rear bump-
ers or the radiator trim are dirty, e.g.
obscured by snow
R there are no, several or unclear lane mark-
ings for a lane, e.g. in areas with road con-
struction work
R the lane markings are worn away, dark or
covered up, e.g. by dirt or snow Driving systems
221Driving and parking Z

Display messages
Possible causes/consequences and
M
MSolutions Radar Sensors
Radar Sensors
Dirty See Opera‐ Dirty See Opera‐
tor's Manual tor's Manual At least one of the following driving systems or driving safety sys-
tems is temporarily restricted or inoperative:
R COLLISION PREVENTION ASSIST PLUS
R PRE-SAFE ®
Brake
R PRE-SAFE ®
PLUS
R Active Lane Keeping Assist
R Active Blind Spot Assist
R DISTRONIC PLUS with Steering Assist and Stop&Go Pilot
If the radar sensor system in front is dirty, Active Blind Spot Assist
will not perform a course-correcting brake application.
Possible causes are:
R the sensors in the radiator trim and/or in the bumpers are dirty.
R the function of the driving system or driving safety system is
impaired due to heavy rain or snow
A warning tone also sounds.
When the causes stated above no longer apply, the display mes-
sage disappears. All driving systems or driving safety systems are
operative again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 170).
X Switch off the engine.
X Clean the sensors in the following locations (Y page 321):
R in the radiator trim
R in the front bumper
R in the rear bumper, particularly in the middle of the rear
bumper
X Restart the engine.
The display message disappears. Display
messages
251On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions ?
Coolant Too Hot Coolant Too Hot
Stop Vehicle Turn Stop Vehicle Turn
Engine Off Engine Off The coolant is too hot.
A warning tone also sounds.
G WARNING
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 170).
X Wait until the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the display message goes out
and the coolant temperature is below 248 ‡ (120 †). Other-
wise, the engine could be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 248 ‡ (120 †). #
See See
Operator's
Operator's Man‐
Man‐
ual
ual The battery is not being charged.
A warning tone also sounds.
Possible causes are:
R a defective alternator
R a torn poly-V-belt
R a malfunction in the electronics
! Do not continue driving. The engine could otherwise overheat.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 170).
X Consult a qualified specialist workshop. Display
messages
259On-board computer and displays Z

Problem
Possible causes/consequences and
M
MSolutions ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator may
be blocked or the electric engine radiator fan may be malfunc-
tioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 170).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and add coolant, observing the warning
notes (Y page 315).
X If you need to add coolant more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the coolant temperature is
below 248 ‡(120 †). Otherwise, the engine could be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-and-go traffic. ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
The coolant temperature has exceeded 248 ‡ (120 †). The air-
flow to the engine radiator may be blocked or the coolant level may
be too low.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
X Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 170).Warning and indicator lamps in the instrument cluster
281On-board computer and displays Z

Problem
Possible causes/consequences and
M
MSolutions X
Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and add coolant, observing the warning
notes (Y page 315).
X If you need to add coolant more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X At coolant temperatures below 248 ‡ (120 †), drive to the
nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-and-go traffic. Driving systems
Problem
Possible causes/consequences and
M MSolutions ·
The red distance warn-
ing lamp lights up while
the vehicle is in motion. A warning tone also
sounds. You are approaching a vehicle, a pedestrian or a stationary obsta-
cle in your line of travel at too high a speed.
X Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to
brake or take evasive action.
Observe the additional information on PRE‑ SAFE®
Brake
(Y page 79).
Observe the additional information on the distance warning func-
tion of COLLISION PREVENTION ASSIST PLUS (Y page 73).282
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Useful information
i This Operator's Manual describes all
models and all standard and optional equip- ment of your vehicle available at the time of
publication of the Operator's Manual.
Country-specific differences are possible.
Please note that your vehicle may not be
equipped with all features described. This
also applies to safety-related systems and
functions.
i Read the information on qualified special-
ist workshops (Y page 26). Engine compartment
Hood
Important safety notes G
WARNING
If the hood is unlatched, it may open up when the vehicle is in motion and block your view.
There is a risk of an accident.
Never unlatch the hood while driving. Before
every trip, ensure that the hood is locked. G
WARNING
When opening and closing the hood, it may
suddenly fall into the closed position. There is a risk of injury to persons within range of
movement of the hood.
Open and close the hood only when no one is
within its range of movement. G
WARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department. G
WARNING
The engine compartment contains moving
components. Certain components, such as
the radiator fan, may continue to run or start
again suddenly when the ignition is off. There is a risk of injury.
If you need to do any work inside the engine
compartment:
R switch off the ignition
R never reach into the area where there is a
risk of danger from moving components,
such as the fan rotation area
R remove jewelry and watches
R keep items of clothing and hair, for exam-
ple, away from moving parts G
WARNING
The ignition system and the fuel injection sys- tem work under high voltage. If you touch
components which are under voltage, you
could get an electric shock. There is a risk of
injury.
Never touch components of the ignition sys-
tem or fuel injection system when the ignition is switched on.
Opening the hood G
WARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Where possible, let the engine cool down and touch only the components described in the
following. G
WARNING
When the hood is open and the windshield
wipers are set in motion, you can be injured by the wiper linkage. There is a risk of injury.
Always switch off the windshield wipers and
the ignition before opening the hood. 312
Engine compartmentMaintenance and care