engine overheat MERCEDES-BENZ C-Class SEDAN 2016 W205 Owner's Manual

GWARNING
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.
GWARNING
If the parking brake has not been fully
released when driving, the parking brake can:
Roverheat and cause a fire
Rlose 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 (
Ypage 44).
SmartKey positions
SmartKey
gTo remove the SmartKey
1Power supply for some consumers, such as
the windshield wipers
2Ignition (power supply for all consumers)
and drive position
3To start the engine
iThe 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 2in the ignition lock. After
approximately 120 seconds the shutters open
automatically. Further information on opening
and cleaning the shutters (
Ypage 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.
146Driving
Driving and parking

In addition to driving style, the actual consump-
tion is affected by other factors, such as:
Rload
Rtire pressure
Rcold start
Rchoice of route
Relectrical 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":
Robserve the gearshift recommendations.
Rdrive 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
(
Ypage 241).
For further information on the ECO display, see
(
Ypage 240).
Braking
Important safety notes
GWARNING
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
GWARNING
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.
182Driving tips
Driving and parking

For more information on driving with snow
chains, see (Ypage 363).
For more information on driving with summer
tires, see (
Ypage 362).
Observe the notes in the "Winter operation" sec-
tion (
Ypage 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
(
Ypage 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:
Rin road and traffic conditions which do not
allow you to maintain a constant speed, e.g. in
heavy traffic or on winding roads
Ron slippery road surfaces. Braking or accel-
erating could cause the drive wheels to lose
traction and the vehicle could then skid
Rwhen 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.
iThe speed indicated in the speedometer
may differ slightly from the speed stored.
Cruise control lever
:Activates or increases speed
;Activates or reduces speed
=Deactivates cruise control
?Activates at the current speed/last stored
speed
When you activate cruise control, the stored
speed is shown in the multifunction display for
five seconds. In addition, the ésymbol
appears in the multifunction display.
Speedometer with segments: when cruise
control is activated, the segments from the
stored speed to the maximum permitted speed
light up.
Storing and maintaining the current
speed
You can store the current speed if you are driv-
ing faster than 20 mph (30 km/h).
Driving systems185
Driving and parking
Z

Change into a lower gearingood time on long
and steep downhillgradients. This isespecially
impo rtant ifthe veh icle isladen. 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 wear-
ing too quickly.
If DI ST RONIC PLUS detects that there isa risk of
a co llisio n, you will be warned visually and
acoustically. DI STRONIC PLUS cannot prevent a
co llisio nwit hout your intervention. An intermit-
tent warning tone willthen sound and the dis-
tance warning lamp willlight up inthe instru-
ment cluster. Brake immediately inorder to
increase the distance to the veh icle infront or
take evasive action pro videdit is safe to doso.
DI ST RONIC PLUS operates inrange between
0 mph (0 km/h) and 120 mph (200 km/h).
Do not use DI STRONIC PLUS while driving on
roads with steep gradients.
As DI STRONIC PLUS transmits radar waves, it
can resemble the radar detectors of the respon-
sible authorities. You can refer to the relevant
chapter inthe Operator's Manual ifquestions
are asked about this.
iUSA only: This device has been approved by
the FCC as a "Vehicular Radar System". The
radar sensor isintended for use inan auto-
motive radar system only. Removal, tamper-
in

g, or altering of the device willvoid any war-
ranties, and isnot permitted bythe FCC. Do
not tamper with, alter, or use inany non-
approved way.
Any unauthorized mod ification to th isdevice
could void the user's authority to operate the
equipm ent.
iCanada only: This device co mplieswit h
RSS -210 of Industry Canada. Operation is
subject to the foll owing 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 isnot permitte d.
Do not tamper with, alter, or use inany non-
approved way.
Any unauthorized mod ification to th isdevice
could void the user's authority to operate the
equipm ent.
Important safety notes
GWARNING
DISTRONIC PLUS does not react to:
Rpeople or animals
Rstationary obstacles on the road, e.g. stop- ped or parked vehicles
Roncoming and crossing traffic
As a result, DI STRONIC PLUS may neither give
warnings nor intervene insuch situations.
There is a risk of an accident.
Alwa ys pay careful attention to the traff icsit-
uation and be ready to brake.
GWARNING
DISTRONIC PLUS cannot always clearly iden-
tify other road users and co mplex traffic sit-
uations.
In such cases, DI STRONIC PLUS may:
Rgive an unnecessary warning and then
brake the vehicle
Rneither givea warning nor intervene
Raccelerate or brake unexpect edly
There isa risk of an accident.
Continue to drive carefully and be ready to
brake, in particular when warned to do so by
DISTRONIC PLU S.
GWARNING
DISTRONIC PLUS brakes your vehicle with up to 50 %of 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:
Rwhen towing the vehicle
Rin the car wash
Driving systems187
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 (
Ypage 237).
Changes in the outside temperature are dis-
played after a short delay.
Coolant temperature display
GWARNING
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 (
Ypage 36). PLUG-IN HYBRID vehicles: the multifunction dis-
play shows the coolant temperature in the
Coolant
submenu (Ypage 246).
Under normal operating conditions and with the
specified coolant level, the coolant temperature may rise to 248 ‡ (120 †).
Operating the on-board computer
:Multifunction display
;Right control panel
=Left control panel
XTo activate the on-board computer: turn
the SmartKey to position 1in the ignition lock.
You can control the multifunction display and
the settings in the on-board computer using the
buttons on the multifunction steering wheel.
Left control panel
òROpens the menu list
9
:Press briefly:
RScrolls in lists
RSelects a menu or function
RIn the RadioorMediamenu:
opens the track or station list and
selects a station, an audio track or
a video scene
RIn the Telephonemenu: switches
to the phone book and selects a
name or a telephone number
236Displays and operation
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
?
CoolantToo HotSto pVehicl eTur nEngine Off
The coolan tis to ohot .
A warning tone also sounds.
GWARNIN G
Do no tdrive when your engin eis overheated. This can caus esom e
fluids whic hmay hav eleaked int oth eengin ecompartmen tto catch
fire.
Steam from th eoverheate dengin ecan also caus eserious burn swhic h
can occur jus tby opening th ehood.
There is aris kof injury.
XPull ove rand stop th evehicl esafely and switch off th eengine, pay-
ing attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 177).
XWait until th eengin ehas cooled down .
XMakesur ethat th eair supply to th eengin eradiato ris no tblocked,
e.g. by snow, slus hor ice .
XDo no tstart th eengin eagain until th edisplay message goe sout and
th ecoolan ttemperature is belo w24 8 ‡ (120†). Otherwise ,th e
engin ecould be damaged.
XPay attention to th ecoolan ttemperature display.
If th etemperatur eincreases again:
XVisit aqualified specialist workshop immediately.
Under normal operating condition sand wit hth especified coolan t
level, th ecoolan ttemperature may ris eto 24 8 ‡(120†).
#
See Operator' sMan ‐ual
The battery is no tbein gcharged.
A warning tone also sounds.
Possibl ecauses are:
Radefective alternato r
Rdefective powerelectronics (PLUG-IN HYBRID vehicles)
Ra torn poly-V-belt
Ramalfunction in th eelectronics
!Do no tcontinu edriving. The engin ecould otherwise overheat.
XPull ove rand stop th evehicl esafely and switch off th eengine, pay-
ing attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 177).
XConsult aqualified specialist workshop .
Display messages269
On-board computer and displays
Z

Display messagesPossible causes/consequences andMSolutions
ServiceRequiredDoNot Shift GearsVisit Dealer
You canno tchang eth etransmission position due to amalfunction .
A warning tone also sounds.
If transmission position Dis selected:
XDrive to aqualified specialist workshop without shifting th etrans -
mission from position D.
If transmission position R,N or Pis selected:
XSecur eth evehicl eagainst rollin gaway (Ypage 177).
XNotify aqualified specialist workshop or breakdown service.
ReversingNotPossi‐bleServic eRequiredYou canno tshift int oth etransmission position Rdue to amalfunction .
The transmission position sP,N or Dcontinu eto be available.
A warning tone also sounds.
XVisit aqualified specialist workshop .
Transmission Mal‐function StopAmalfunction has occurred in th emechanical transmission compo -
nents.
A warning tone also sounds. The gearbox automatically shift sto posi-
tion N.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XShift th etransmission to position P.
XSecureth evehicl eagainst rollin gaway (Ypage 177).
XNotify aqualified specialist workshop or breakdown service.
Sto pVehicl eLeaveEngineRunnin gWaitTransmission Cool‐ing
PLUG-I NHYBRID vehicles:
The transmission has overheated. Pullin gaway can be temporarily
impaire dor no tpossible.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions. Do no tcontinu edrivin g
under any circumstances.
XLeav eth eengin erunning.
XWait until th edisplay message disappear sbefore pullin gaway.
Auxiliary Batter yMalfunctionPLUG-INHYBRID vehicles only:
The auxiliary battery for th etransmission is no longer bein gcharged.
XVisit aqualified specialist workshop .
XUntilthen ,set th etransmission to position Pbefore you switch off
th eengine.
XBefor eleaving th evehicle, apply th eelectric parking brake.
NThe trunk lid is open .
XCloseth etrunk lid.
Display messages28 3
On-board computer and displays
Z

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
?NThe red coolant warning lamp comes on while the engine is running.
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 malfunctioning.
The coolant is too hot and the engine is no longer being cooled sufficiently.
XObserve the additional display messages in the multifunction display.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 177).
XLeave the vehicle and keep a safe distance from the vehicle until the engine has cooled down.
XCheck the coolant level and add coolant, observing the warning notes
(Ypage 333).
XIf you have to add coolant frequently, have the engine cooling system checked.
XMake sure that the air supply to the engine radiator is not blocked, e.g. by snow,
slush or ice.
XDo not start the engine again until the coolant temperature is below 248 ‡
(120 †). Otherwise, the engine could be damaged.
XDrive to the nearest qualified specialist workshop.
XAvoid heavy loads on the engine as you do so, e.g. driving in mountainous terrain
and stop-start traffic.
?N The red coolant warning lamp comes on while the engine is running. A warning
tone also sounds.
The coolant temperature has exceeded 248 ‡(120 †). The airflow to the engine
radiator may be blocked or the coolant level may be too low.
GWARNING
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.
XObserve the additional display messages in the multifunction display.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 177).
XLeave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
XCheck the coolant level and add coolant, observing the warning notes
(Ypage 333).
XIf you have to add coolant frequently, have the engine cooling system checked.
XMake sure that the air supply to the engine radiator is not blocked, e.g. by snow,
slush or ice.
294Warning and indicator lamps in the instrument cluster
On-board computer and displays

Engine compartment
Hood
Important safety notes
GWARNING
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.
GWARNING
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.
GWARNING
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.
GWARNING
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:
Rswitch off the ignition
Rnever reach into the area where there is a
risk of danger from moving components,
such as the fan rotation area
Rremove jewelry and watches
Rkeep items of clothing and hair, for exam-
ple, away from moving parts
GWARNING
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
GWARNING
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.
GWARNING
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.
330Engine compartment
Maintenance and care

Additives
!Do notuse any additive sin th eengin eoil.
This could damag eth eengine.
Brake fluid
GWARNIN G
The brak efluid constantl yabsorbs moisture
from th eair. This lower sth eboiling poin tof
th ebrak efluid .If th eboiling poin tof th ebrak e
fluid is to olow, vapo rpockets may for min th e
brak esystem when th ebrakes are applie d
hard. This would impair braking efficiency.
There is aris kof an accident.
You should hav eth ebrak efluid renewed at
th especifie dintervals.
When handlin gbrak efluid ,observ eth eimpor-
tan tsafet ynote son servic eproducts
(
Ypage 388).
The brak efluid chang eintervals can be foun din
th eMaintenance Booklet .
Only use brak efluid approve dby Mercedes-
Benz in accordanc ewit hMB-Freigabe or MB -
Approval 331.0.
Information about approve dbrak efluid can be
obtained at any qualified specialis tworkshop or
on th eInternet at
http://bevo.mercedes-benz.co m.
iHave 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
GWARNING
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.
iHave 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
(
Ypage 388).
The coolant is a mixture of water and anti-
freeze/corrosion inhibitor. It performs the fol-
lowing tasks:
Rcorrosion protection
Rantifreeze protection
Rraising 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:
Rbe at least 50%. This will protect the engine
cooling system against freezing down to
approximately -35 ‡ (-37 †).
Rnot 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
with MB Specifications for Service Products
310.1.
iWhen the vehicle is first delivered, it is filled
with a coolant mixture that ensures adequate
antifreeze and corrosion protection.
392Service products and filling capacities
Technical data