2015 MERCEDES-BENZ CLA-Class engine overheat

G
WARNING
Unsuitable footwear can hinder correct usage of the pedals, e.g.:
R shoes with thick soles
R shoes with high heels
R slippers
There is a risk of an accident.
Wear suitable footwear to ensure correct
usage of the pedals. G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect, for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk of an accident.
Do not switch off the ignition while driving. G
WARNING
If the parking brake has not been fully
released when driving, the parking brake can:
R overheat and cause a fire
R lose its hold function.
There is a risk of fire and an accident. Release
the parking brake fully before driving off.
! Do not warm up the engine with the vehi-
cle stationary. Drive off immediately. Avoid high engine speeds and driving at full throt-
tle until the engine has reached its operat-
ing temperature.
Only shift the automatic transmission to
the desired drive position when the vehicle is stationary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery
roads. You could otherwise damage the
drive train.
! AMG vehicles:
avoid full-load operation
and engine speeds greater than 5000 rpm
when the engine is cold. This helps to pro- tect the engine and avoids uncomfortable
driving. Key positions
SmartKey g
To remove the SmartKey
(shift the transmission to position P)
1 Power supply for some consumers, such
as the windshield wipers
2 Ignition (power supply for all consumers)
and drive position
3 To start the engine
i The SmartKey can be turned in the igni-
tion lock even if it is not the correct Smart- Key for the vehicle. The ignition is not
switched on. The engine cannot be started.
Start/Stop button General notes
Vehicles with KEYLESS-GO are equipped with
SmartKeys featuring the integrated KEYLESS-
GO function and a detachable Start/Stop but-
ton.
A check which periodically establishes a radio connection between the vehicle and the
SmartKey determines whether a valid Smart-Key is in the vehicle. This occurs, for example,
when starting the engine.
When you insert the Start/Stop button into
the ignition lock, the system needs approx-
imately two seconds recognition time. You
can then use the Start/Stop button. Driving
141Driving and parking Z

Holding the vehicle stationary on uphill
gradients G
WARNING
If the clutch overheats, the electronic man-
agement system is automatically deactivated. This interrupts the power transmission. The
vehicle may, for example, roll backwards on
gradients. There is a risk of an accident.
Never hold the vehicle stationary on uphill
gradients by depressing the accelerator.
The clutch may overheat if you hold the vehi- cle stationary on uphill gradients by depress- ing the accelerator pedal. If the clutch over-
heats, a warning tone sounds.
All vehicles (except AMG vehicles): the
Stop
Stop Vehicle Vehicle Shift
Shiftto
toP
PLeave
Leave Engine
Engine
Running
Running display message appears in the mul-
tifunction display. You will only be able to
continue your journey once the clutch has
cooled down and the display message in the
multifunction display has disappeared.
AMG vehicles: theTrans. Oil Overhea‐ Trans. Oil Overhea‐
ted Drive on with Care
ted Drive on with Care display message
appears in the multifunction display.
Never hold the vehicle stationary on uphill
gradients by depressing the accelerator.
Instead, only ever hold the vehicle stationary
on uphill gradients by:
R depressing the brake pedal
R activating the HOLD function
R engaging the electric parking brake
Kickdown Use kickdown for maximum acceleration.
X Depress the accelerator pedal beyond the
pressure point.
The automatic transmission shifts to a
lower gear depending on the engine speed.
X Ease off the accelerator pedal once the
desired speed is reached.
The automatic transmission shifts back up.
AMG vehicles: it is only possible to use kick-
down in the automatic drive program and the temporary manual drive program
M. When
manual drive program Mis permanently acti-
vated, kickdown is not possible.
For further information on kickdown in man-
ual drive program M(Y page 155).
Rocking the vehicle free Shifting the transmission repeatedly between
gears Dand Rmay help to free the vehicle if it
has become stuck in slush or snow. The vehi- cle's engine management system limits the
speed to a maximum of 5 mph (9 km/h) when
shifting back and forth. To shift back and forth
between transmission positions Dand R,
move the DIRECT SELECT lever up and down past the point of resistance. Program selector button
The program selector button allows you to
choose between drive programs with differ-
ent driving characteristics. X
All vehicles (except AMG vehicles):
press program selector button :.
The selected drive program appears in the
multifunction display. Automatic transmission
153Driving and parking Z

effect, the drive wheels could lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on a slippery road surface.
Downhill gradients !
On long and steep gradients, you must
reduce the load on the brakes by shifting to
a lower gear in good time. This allows you to
take advantage of the engine's braking
effect. For this, you need to have selected
manual drive program M. This helps you to
avoid overheating the brakes and wearing
them out excessively.
When you take advantage of the engine's
braking effect, a drive wheel may not turn
for some time, e.g. on a slippery road sur-
face. This could cause damage to the drive train. This type of damage is not covered bythe Mercedes-Benz warranty.
Briefly depressing the accelerator pedal on
downhill gradients while the manual drive
program Mis temporarily activated: the auto-
matic transmission may switch to the last
active automatic drive program Eor S. The
automatic transmission may shift to a higher
gear. This can reduce the engine's braking
effect.
Heavy and light loads G
WARNING
If you rest your foot on the brake pedal while
driving, the braking system can overheat. This increases the stopping distance and can even
cause the braking system to fail. There is a
risk of an accident.
Never use the brake pedal as a footrest. Never
depress the brake pedal and the accelerator
pedal at the same time.
! Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads. If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately.
Drive on for a short while. This allows the air-
flow to cool the brakes more quickly.
Wet roads If you have driven for a long time in heavy rain
without braking, there may be a delayed reac- tion from the brakes when braking for the firsttime. This may also occur after the vehicle has
been washed or driven through deep water.
You have to depress the brake pedal more
firmly. Maintain a greater distance from the
vehicle in front.
After driving on a wet road or having the vehi-
cle washed, brake firmly while paying atten-
tion to the traffic conditions. This will warm up the brake discs, thereby drying them more
quickly and protecting them against corro-
sion.
Limited braking performance on salt-
treated roads If you drive on salted roads, a layer of salt
residue may form on the brake discs and
brake pads. This can result in a significantly
longer braking distance.
R In order to prevent any salt build-up, apply
the brakes occasionally while paying atten-
tion to the traffic conditions.
R Carefully depress the brake pedal and the
beginning and end of a journey.
R Maintain a greater distance to the vehicle
ahead.
Servicing the brakes !
If the red brake warning lamp lights up in
the instrument cluster and you hear a warn- ing tone while the engine is running, the
brake fluid level may be too low. Observe
additional warning messages in the multi-
function display.
The brake fluid level may be too low due to brake pad wear or leaking brake lines. 166
Driving tipsDriving and parking

becomes trapped in snow. There is a risk of
fatal injury.
If you leave the engine or the auxiliary heating running, make sure the exhaust pipe and area
around the vehicle are clear of snow. To
ensure an adequate supply of fresh air, open a window on the side of the vehicle that is not
facing into the wind.
Have your vehicle winter-proofed at a quali-
fied specialist workshop at the onset of win-
ter.
Drive particularly carefully on slippery road
surfaces. Avoid sudden acceleration, steering
and braking maneuvers. Do not use the cruise
control or DISTRONIC PLUS.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:
X Shift the transmission to position N.
X Try to bring the vehicle under control using
corrective steering.
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Changes in the outside temperature are dis-
played after a short delay.
Indicated temperatures just above the freez-
ing point do not guarantee that the road sur-
face is free of ice. The road may still be icy,
especially in wooded areas or on bridges.
You should pay special attention to road con-
ditions when temperatures are around freez-
ing point.
For more information on driving with snow
chains, see (Y page 321).
For more information on driving with summer
tires, see (Y page 320).
Observe the notes in the "Winter operation"
section (Y page 320). Driving systems
Cruise control
General notes Cruise control maintains a constant road
speed for you. It brakes automatically in order to avoid exceeding the set speed. On long and
steep downhill gradients, especially if the
vehicle is laden, you must select a low gear in
good time. For this, you will need to have
selected manual drive program M
(Y page 155). By doing so, you will make use
of the braking effect of the engine. This
relieves the load on the brake system and
prevents the brakes from overheating and
wearing too quickly.
Use cruise control only if road and traffic con- ditions make it appropriate to maintain a
steady speed for a prolonged period. You canstore any road speed above 20 mph
(30 km/h).
The speed indicated in the speedometer maydiffer slightly from the speed stored.
Important safety notes If you fail to adapt your driving style, cruise
control can neither reduce the risk of an acci-
dent nor override the laws of physics. Cruise
control cannot take into account the road,
traffic and weather conditions. Cruise control
is only an aid. You are responsible for the dis-
tance to the vehicle in front, for vehicle speed, for braking in good time and for staying in
your lane.
Do not use cruise control:
R in road and traffic conditions which do not
allow you to maintain a constant speed e.g.
in heavy traffic or on winding roads
R on slippery road surfaces. Braking or accel-
erating could cause the drive wheels to lose
traction and the vehicle could then skid
R when there is poor visibility, e.g. due to fog,
heavy rain or snow
If there is a change of drivers, advise the new driver of the speed stored. Driving systems
169Driving and parking Z

press the cruise control lever up
:or
down ?to the pressure point.
The last stored speed increases or decrea- ses in 5 mph (10 km/h) increments.
i Cruise control is not deactivated if you
depress the accelerator pedal. For exam-
ple, if you accelerate briefly to overtake,
cruise control adjusts the vehicle's speed
to the last speed stored after you have fin- ished overtaking.
Deactivating cruise control There are several ways to deactivate cruise
control:
X Briefly press the cruise control lever for-
wards =.
or
X Brake.
Cruise control is automatically deactivated if: R the vehicle is secured with the electric
parking brake
R you are driving at less than 20 mph
(30 km/h)
R ESP ®
intervenes or you deactivate ESP ®
R you shift the transmission to position N
while driving
If cruise control is deactivated, you will hear a warning tone. You will see the Cruise Con‐
Cruise Con‐
trol Off trol Off message in the multifunction dis-
play for approximately five seconds.
i When you switch off the engine, the last
speed stored is cleared. DISTRONIC PLUS
General notes DISTRONIC PLUS regulates the speed and
automatically helps you maintain the dis-
tance to the vehicle detected in front. Vehi-
cles are detected with the aid of the radar
sensor system. DISTRONIC PLUS brakes
automatically to avoid exceeding the set speed or to maintain the designated distance
from the vehicle in front.
Change into a lower gear in good time on long
and steep downhill gradients. This is espe-
cially important if the vehicle is laden. By
doing so, you will make use of the braking
effect of the engine. This relieves the load on
the brake system and prevents the brakes
from overheating and wearing too quickly.
If DISTRONIC PLUS detects that there is a risk of a collision, you will be warned visually and
acoustically. DISTRONIC PLUS cannot pre-
vent a collision without your intervention. An
intermittent warning tone will then sound and the distance warning lamp will light up in the
instrument cluster. Brake immediately in
order to increase the distance to the vehicle
in front or take evasive action provided it is
safe to do so.
DISTRONIC PLUS operates in range between 0 mph (0 km/h) and 120 mph (200 km/h).
Do not use DISTRONIC PLUS while driving onroads with steep gradients.
Important safety notes G
WARNING
DISTRONIC PLUS does not react to:
R people or animals
R stationary obstacles on the road, e.g. stop-
ped or parked vehicles
R oncoming and crossing traffic
As a result, DISTRONIC PLUS may neither give
warnings nor intervene in such situations.
There is a risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake. G
WARNING
DISTRONIC PLUS cannot always clearly iden- tify other road users and complex traffic sit-
uations. Driving systems
171Driving and parking
Z

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 24). Important safety notes
G
WARNING
If you operate information systems and com-
munication equipment integrated in the vehi- cle while driving, you will be distracted from
traffic conditions. You could also lose control of the vehicle. There is a risk of an accident.
Only operate the equipment when the traffic
situation permits. If you are not sure that this
is possible, park the vehicle paying attention
to traffic conditions and operate the equip-
ment when the vehicle is stationary.
You must observe the legal requirements for
the country in which you are currently driving when operating the on-board computer. G
WARNING
If the instrument cluster has failed or mal-
functioned, you may not recognize function
restrictions in systems relevant to safety. The operating safety of your vehicle may be
impaired. There is a risk of an accident.
Drive on carefully. Have the vehicle checked
at a qualified specialist workshop immedi-
ately.
The on-board computer only shows messages
or warnings from certain systems in the mul- tifunction display. You should therefore make sure your vehicle is operating safely at all
times.
If the operating safety of your vehicle is
impaired, pull over as soon as it is safe to do
so. Contact a qualified specialist workshop.
For an overview, see the instrument panel
illustration (Y page 31). Displays and operation
Instrument cluster lighting
The light sensor in the instrument cluster
automatically controls the brightness of the
multifunction display. In daylight, the displays
in the instrument cluster are not illuminated.
The lighting in the instrument cluster, in the
displays and the controls in the vehicle inte-
rior can be adjusted using the brightness con- trol knob.
The brightness control knob is located on the
bottom left of the instrument cluster
(Y page 31).
X Turn the brightness control knob clockwise
or counter-clockwise.
If the light switch is set to Ã,Tor
L, the brightness is dependent upon
the brightness of the ambient light. Coolant temperature display
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.
! A display message is shown if the coolant
temperature is too high. 200
Displays and operationOn-board computer and displays

Engine
Display messages
Possible causes/consequences and
M
MSolutions +
Check Coolant Check Coolant
Level See Opera‐ Level See Opera‐
tor's Manual tor's Manual The coolant level is too low.
! Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
X Add coolant, observing the warning notes before doing so
(Y page 289).
X If coolant needs to be added more often than usual, have the
engine coolant system checked at a qualified specialist work-
shop. ? The fan motor is faulty.
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. ?
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 160).
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 †). Display messages
233On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions #
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 160).
X Consult a qualified specialist workshop. #
Stop Vehicle See Stop Vehicle See
Operator's Manual Operator's Manual The battery is no longer being charged and the battery charge level
is too low.
A warning tone also sounds.
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 160).
X Observe the instructions in the #See SeeOperator's
Operator's Manual
Manual
display message.
X Consult a qualified specialist workshop. 4
Check Engine Oil Check Engine Oil
When When
Next
NextRefueling
Refueling The engine oil level has dropped to the minimum level.
A warning tone also sounds.
! Avoid long journeys with too little engine oil. The engine will
otherwise be damaged.
X Check the oil level when next refueling, at the latest
(Y page 288).
X If necessary, add engine oil (Y page 288).
X Have the engine checked at a qualified specialist workshop if
engine oil needs to be added more often than usual.
Information on approved engine oils can be obtained from any
qualified specialist workshop or on the Internet at http://
bevo.mercedes-benz.com. æ
Fuel Level Low Fuel Level Low The fuel level has dropped into the reserve range.
X Refuel at the nearest gas station. 234
Display
messagesOn-board computer and displays