2016 MERCEDES-BENZ C CLASS engine overheat

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 vehicle
stationary. Drive off immediately. Avoid high
engine speeds and driving at full throttle until
the engine has reached its operating temper-
ature.
Only shift the automatic transmission to the
desired drive position when the vehicle is sta-
tionary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery roads.
You could otherwise damage the drive train.
! Mercedes-AMG vehicles: at low engine oil
temperatures below 68 ‡ (+20 †), the max-
imum engine speed is restricted in order to
protect the engine. To protect the engine and
maintain smooth engine operation, avoid driv-
ing at full throttle when the engine is cold.
Observe the important safety notes for PLUG-IN
HYBRID vehicles ( Y
page 44). SmartKey positions
SmartKey
Z
To remove the SmartKey G
Power supply for some consumers, such as
the windshield wipers H
Ignition (power supply for all consumers)
and drive position I
To start the engine
i The SmartKey can be turned in the ignition
lock even if it is not the correct SmartKey for
the vehicle. The ignition is not switched on.
The engine cannot be started.
Vehicles with AIRPANEL: you can open the
shutters in the radiator trim by turning the
SmartKey to position 2 in the ignition lock. After
approximately 120 seconds the shutters open
automatically. Further information on opening
and cleaning the shutters ( Y
page 339).
Start/Stop button
General notes
When you insert the Start/Stop button into the
ignition lock, the system needs approximately
two seconds recognition time. You can then use
the Start/Stop button.
Pressing the Start/Stop button several times in
succession corresponds to the different key
positions in the ignition lock. This is only the
case if you are not depressing the brake pedal.
If you depress the brake pedal and press the
Start/Stop button, the engine starts immedi-
ately.
A check which periodically establishes a radio
connection between the vehicle and the Smart-
Key determines whether a valid SmartKey is in
the vehicle. This occurs, for example, when
starting the engine.146
Driving
Driving and parking

In addition to driving style, the actual consump-
tion is affected by other factors, such as: R
load R
tire pressure R
cold start R
choice of route R
electrical consumers switched on
These factors are not included in the ECO dis-
play.
An economical driving style specially requires
driving at moderate engine speeds.
Achieving a higher value in the categories
"Acceleration" and "Constant": R
observe the gearshift recommendations. R
drive in drive program E .
On long journeys at a constant speed, e.g. on the
highway, only the outer area for "constant" will
change.
The ECO display summarizes the driving style
from the start of the journey to its completion.
Therefore, there are more marked changes in
the outer areas at the start of a journey. On lon-
ger journeys, there are fewer changes. For more
marked changes, perform a manual rest
( Y
page 241).
For further information on the ECO display, see
( Y
page 240).
Braking
Important safety notes
G WARNING
If you shift down on a slippery road surface in
an attempt to increase the engine's braking
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 early
to a lower gear. This allows you to take
advantage of the engine braking effect and
helps avoid overheating and excessive wear
of the brakes. When you take advantage of the engine brak-
ing effect, a drive wheel may not turn for some
time, e.g. on a slippery road surface. This
could cause damage to the drive train. This
type of damage is not covered by the
Mercedes-Benz warranty.
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 airflow 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 first
time. 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 vehicle
washed, brake firmly while paying attention to
the traffic conditions. This will warm up the
brake discs, thereby drying them more quickly
and protecting them against corrosion.
Limited braking performance on salt-
treated roads
If you drive on salted roads, a layer of salt resi-
due may form on the brake discs and brake
pads. This can result in a significantly longer
braking distance.182
Driving tips
Driving and parking

For more information on driving with snow
chains, see ( Y
page 363).
For more information on driving with summer
tires, see ( Y
page 362).
Observe the notes in the "Winter operation" sec-
tion ( Y
page 362).
Driving systems
Mercedes-Benz Intelligent Drive Mercedes-Benz Intelligent Drive stands for inno-
vative driver assistance and safety systems
which enhance comfort and support the driver in
critical situations. With these intelligent co-ordi-
nated systems Mercedes-Benz has set a mile-
stone on the path towards autonomous driving.
Mercedes-Benz Intelligent Drive embraces all
elements of active and passive safety in one well
thought out system – for the safety of the vehi-
cle occupants and that of other road users.
Further information on driving safety systems
( Y
page 67).
Cruise control
General notes Cruise control maintains a constant road speed
for you. It brakes automatically in order to avoid
exceeding the set speed. Change into a lower
gear in good time on long and steep downhill
gradients. This is especially 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.
Use cruise control only if road and traffic con-
ditions make it appropriate to maintain a steady
speed for a prolonged period. You can store any
road speed above 20 mph (30 km/h).
Important safety notes
If you fail to adapt your driving style, cruise con-
trol can neither reduce the risk of an accident
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 distance 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.
i The speed indicated in the speedometer
may differ slightly from the speed stored.
Cruise control lever
C
Activates or increases speed D
Activates or reduces speed

Change into a lower gear in good time on long
and steep downhill gradients. This is especially
impo rtant if the veh icle is laden. By doin g 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 wear-
ing too quic kly.
If DI ST RONIC PLUS detects that there is a risk of
a co llisio n, you will be warned visually and
acoustically. DI ST RONIC PLUS cannot prevent a
co llisio n wit hout your intervention. An intermit-
tent warning tone will then sound and the dis-
tance warning lamp will light up in the instru-
ment cluster. Brake immediately in order to
increase the dist ance to the veh icle in front or
take evasive action pro vide d it is safe to do so.
DI ST RONIC PLUS operates in range between
0 mph (0 km/h) and 120 mph (200 km/h).
Do not use DI ST RONIC PLUS while driv ing on
roads wit h steep gradients.
As DI ST RONIC PLUS transmits radar waves, it
can resemble the radar detectors of the respon-
sible authorities. You can refer to the relevant
chapter in the Operator's Manual if questions
are asked about this.
i USA only: This device has been appr oved by
the FCC as a "Vehicular Radar System". The
radar sensor is intended for use in an auto-
motive radar system only. Removal, tamper-
in g , or altering of the device will void any war-
ranties, and is not permitted by the FCC. Do
not tamper with, alter, or use in any non-
approved way.
Any unauthorized mod ific ation to th is device
could void the user's authority to operate the
equipm ent.
i Canada only: This device co mplie s wit h
RSS -210 of In dustry Canada. Operation is
subject to the foll owin g two conditions:
1. This device may not cause harmful inter-
ference, and
2. This device must accept any interference
receive d, inc ludin g interference that may
cause undesired operation of the device.
Removal, tampering, or altering of the device
will void any warranties, and is not permitte d.
Do not tamper wit h, alter, or use in any non-
approved way.
Any unauthorized mod ific ation to th is device
could void the user's authority to operate the
equipm ent. 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, DI ST RONIC PLUS may neither give
warnings nor intervene in such situations.
There is a risk of an accident.
Alwa ys pay careful attention to the traff ic sit-
uation and be ready to brake.
G WARNING
DISTRONIC PLUS cannot always clearly iden-
tify other road users and co mple x traffic sit-
uations.
In such cases, DI ST RONIC PLUS may: R
give an unnecessary warning and then
brake the vehicle R
neither give a warning nor intervene R
accelerate or brake unexpect edly
There is a risk of an accident.
Continue to drive carefully and be ready to
brake, in particular when warned to do so by
DISTRONIC PLU S.
G WARNING
DISTRONIC PLUS brakes your vehicle with up
to 50 %o f the maximum possible deceleration.
If this braking force is insufficient, DISTRONIC
PLUS warns you visually and audibly. There is
a risk of an accident.
In such cases, apply the brakes yourself and
try to take evasive action.
! If DISTRONIC PLUS or the HOLD function is
activated, the vehicle brakes automatically in
certain situations.
To prevent damage to the vehicle, deactivate
DISTRONIC PLUS and the HOLD function in
the following or other similar situations: R
when towing the vehicle R
in the car washDriving systems 187
Driving and parking Z

The segments between the speed of the vehi-
cle in front and the stored speed light up.
Tachometer
! Do not drive in the overrevving range, as this
could damage the engine.
The red band in the tachometer indicates the
engine's overrevving range.
The fuel supply is interrupted to protect the
engine when the red band is reached.
Outside temperature display You should pay special attention to road condi-
tions when temperatures are around freezing
point.
Bear in mind that the outside temperature dis-
play indicates the temperature measured and
does not record the road temperature.
The outside temperature display is in the multi-
function display ( Y
page 237).
Changes in the outside temperature are dis-
played after a short delay.
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.
If the coolant temperature is over 248 ‡
(120 †), do not continue driving. The engine
will otherwise be damaged.
All vehicles except PLUG-IN HYBRID vehicles:
the coolant temperature display is in the lower
section of the tachometer ( Y
page 36). PLUG-IN HYBRID vehicles: the multifunction dis-
play shows the coolant temperature in the
Coolant submenu ( Y
page 246).
Under normal operating conditions and with the
specified coolant level, the coolant temperature
may rise to 248 ‡ (120 †).
Operating the on-board computer
C
Multifunction display D
Right control panel

Display messages
Possible causes/consequences and P Solutions
Servic e Required Do
Not Shift Gears
Visit Dealer You canno t chang e th e transmission position due to a malfunction .
A warning tone also sounds.
If transmission position D is selected:X
Drive to a qualified specialist workshop without shifting th e trans -
mission from position D .
If transmission position R , N or P is selected:X
Secur e th e vehicl e against rollin g away ( Y
page 177).X
Notify a qualified specialist workshop or breakdown service.
Reversing Not Possi‐
ble Servic e Required You canno t shift int o th e transmission position R due to a malfunction .
The transmission position s P , N or D continu e to be available.
A warning tone also sounds. X
Visit a qualified specialist workshop .
Transmission Mal ‐
function Sto p A malfunction has occurred in th e mechanical transmission compo -
nents.
A warning tone also sounds. The gearbox automatically shift s to posi-
tion N . X
Pull ove r and stop th e vehicl e safely as soo n as possible, payin g
attention to roa d and traffic conditions.X
Shift th e transmission to position P .X
Secur e th e vehicl e against rollin g away ( Y
page 177).X
Notify a qualified specialist workshop or breakdown service.
Sto p Vehicl e Leave
Engine Runnin g Wai t
Transmission Cool‐
ing PLUG-I N HYBRID vehicles:
The transmission has overheated. Pullin g away can be temporarily
impaire d or no t possible.X
Pull ove r and stop th e vehicl e safely as soo n as possible, payin g
attention to roa d and traffic conditions. Do no t continu e drivin g
under any circumstances. X
Leav e th e engin e running.X
Wait until th e display message disappear s before pullin g away.
Auxiliary Batter y
Malfunction PLUG-I N HYBRID vehicles only:
The auxiliary battery for th e transmission is no longer bein g charged.X
Visit a qualified specialist workshop .X
Unti l then , set th e transmission to position P before you switch off
th e engine. X
Befor e leaving th e vehicle, apply th e electric parking brake.

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.
! Make sure that the windshield wipers are
not folded away from the windshield. You
could otherwise damage the windshield wip-
ers or the hood.330
Engine compartment
Maintenance and care

Additives
! Do no t use any additive s in th e engin e oil.
This could damag e th e engine.
Brake fluid
G WARNIN G
The brak e fluid constantl y absorbs moisture
from th e air. This lower s th e boiling poin t of
th e brak e fluid . If th e boiling poin t of th e brak e
fluid is to o low, vapo r pockets may for m in th e
brak e system when th e brakes are applie d
hard. This would impair braking efficiency.
There is a ris k of an accident.
You should hav e th e brak e fluid renewed at
th e specifie d intervals.
When handlin g brak e fluid , observ e th e impor-
tan t safet y note s on servic e products
( Y
page 388).
The brak e fluid chang e intervals can be foun d in
th e Maintenance Booklet .
Only use brak e fluid approve d by Mercedes-
Benz in accordanc e wit h MB-Freigabe or MB -
Approval 331.0.
Information about approve d brak e fluid can be
obtained at any qualified specialis t workshop or
on th e Internet at
http://bevo.mercedes-benz.co m.
i Have the brake fluid regularly replaced at a
qualified specialist workshop in accordance
with the replacement intervals and the
replacement confirmed in the Maintenance
Booklet.
Coolant
Important safety notes
G WARNING
If antifreeze comes into contact with hot com-
ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Let the engine cool down before you add anti-
freeze. Make sure that antifreeze is not spilled
next to the filler neck. Thoroughly clean the antifreeze from components before starting
the engine.
! Only add coolant that has been premixed
with the desired antifreeze protection. You
could otherwise damage the engine.
Further information on coolants can be found
in the Mercedes-Benz Specifications for Ser-
vice Products, MB BeVo 310.1, e.g. on the
Internet at http://bevo.mercedes-benz.com.
Or contact a qualified specialist workshop.
! Always use a suitable coolant mixture, even
in countries where high temperatures prevail.
Otherwise, the engine cooling system is not
sufficiently protected from corrosion and
overheating.
i Have the coolant regularly replaced at a
qualified specialist workshop and the replace-
ment confirmed in the Maintenance Booklet.
Comply with the important safety precautions
for service products when handling coolant
( Y
page 388).
The coolant is a mixture of water and anti-
freeze/corrosion inhibitor. It performs the fol-
lowing tasks: R
corrosion protection R
antifreeze protection R
raising the boiling point
If the coolant has antifreeze protection down to
-35 ‡ (-37 †), the boiling point of the coolant
during operation is approximately 266 ‡
(130 †).
The antifreeze/corrosion inhibitor concentra-
tion in the engine cooling system should: R
be at least 50%. This will protect the engine
cooling system against freezing down to
approximately -35 ‡ (-37 †). R
not exceed 55% (antifreeze protection down
to -49 ‡ [-45 †]). Otherwise, heat will not be
dissipated as effectively.
Mercedes-Benz recommends an antifreeze/
corrosion inhibito r concentra te in accordance
w
ith MB Specifications for Service Products
310.1.
i When the vehicle is first delivered, it is filled
with a coolant mixture that ensures adequate
antifreeze and corrosion protection.392
Service products and filling capacities
Technical data