heating MERCEDES-BENZ S-CLASS COUPE 2014 Service Manual

effect, the drive wheels could lose their grip.
This increases the risk of skidding and having an accident.
Do not shift down for additional engine brak-
ing on a slippery road surface.
Downhill gradients Change into a lower gear in good time on long
and steep downhill gradients. Take particular
note of this when driving a laden vehicle.
This also applies if you have activated cruise
control, SPEEDTRONIC or DISTRONIC PLUS.
This will use the braking effect of the engine,
so less braking will be required to maintain
vehicle speed. This relieves the load on the
brake system and prevents the brakes from
overheating and wearing too quickly.
Heavy and light loads G
WARNING
The braking system can overheat if you leave your foot on the brake pedal while driving.
This increases the braking distance and could
even cause the braking system to fail. There is
a risk of an accident.
Never use the brake pedal as a footrest. Do
not simultaneously depress both the brake
pedal and the accelerator pedal while driving.
! Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads.
If heavy demands are made on the brakes, do not park the vehicle immediately. Drive on for
a short while. This allows the airflow to cool
the brakes more quickly.
If the brakes have been used only moderately,
you should occasionally test their effective-
ness. To do this, brake more firmly from a
higher speed while paying attention to the
traffic conditions. This improves the grip of
the brakes. Wet road surfaces 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 a car wash orafter driving through deep water.
You will have to depress the brake pedal more
firmly. Maintain a greater distance to the vehi-
cle 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 salt-treated roads, a layer of
salt may form on the brake discs and pads.
This can increase the braking distance con-
siderably.
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 at the
end of the journey and when starting the
next journey.
R Maintain a much greater distance to the
vehicle in front.
New brake discs and brake pads/
linings Brake pads/linings and discs that are either
new or have been replaced only achieve opti-
mum braking effect after several hundred kil-
ometres of driving. Compensate for the
reduced braking effect by applying greater
force to the brake pedal. Driving tips
183Driving and parking Z

age the engine, the electronics or the trans-
mission.
If you have to drive on stretches of road on
which water has collected, please bear in
mind that:
R the maximum permissible still water depth
when the vehicle is raised is 25 cm
R you should drive no faster than walking
pace Winter driving
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.
This increases the risk of skidding and having
an accident.
Do not shift down for additional engine brak-
ing on a slippery road surface. G
DANGER
If the exhaust pipe is blocked or adequate
ventilation is not possible, poisonous gases
such as carbon monoxide (CO) may enter the vehicle. This is the case, e.g. if the vehicle
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 winterproofed at a qualified specialist workshop at the onset of winter.
You should drive particularly carefully on slip-
pery road surfaces. Avoid sudden accelera-
tion, steering and braking manoeuvres. Do
not use cruise control or DISTRONIC PLUS. If the vehicle threatens to skid or cannot be
stopped when moving at low speed:
X Move the transmission to position N.
X Try to bring the vehicle under control by
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 the
freezing point.
For more information on driving with snow
chains, see (Y page 379).
For more information on driving with summer tyres, see (Y page 378).
Observe the notes in the "Winter operation"
section (Y page 378). Driving systems
Mercedes-Benz Intelligent Drive
Mercedes-Benz Intelligent Drive stands for
innovative driver assistance and safety sys-
tems which enhance comfort and support the
driver in critical situations. With these intelli-
gent co-ordinated systems Mercedes-Benz
has set a milestone 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
vehicle occupants and that of other road
users.
Further information on driving safety systems (Y page 69). Driving systems
185Driving and parking Z

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. Take particular note of
this when driving a laden vehicle. 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 over-
heating and wearing too quickly.
Use cruise control only if road and traffic con-
ditions are appropriate for maintaining a
steady speed for a prolonged period. You can store any road speed above 30 km/h.
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 road,
weather or traffic 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
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 smooth or slippery roads. Braking or
accelerating can 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. Cruise control lever
:
To store the current speed or a higher
speed
; LIM indicator lamp
= To store the current speed and call up the
last stored speed
? To store the current speed or a lower
speed
A To switch between cruise control and var-
iable SPEEDTRONIC
B To deactivate cruise control
You can operate cruise control and variable
SPEEDTRONIC with the cruise control lever.
The LIM indicator lamp on the cruise control
lever indicates which system you have selec-
ted:
R LIM indicator lamp off: cruise control is
selected.
R LIM indicator lamp on: variable SPEED-
TRONIC is selected.
When you activate cruise control, the stored
speed is shown in the multifunction display
for five seconds. In the speedometer, the seg-
ments between the stored speed and the
maximum speed light up. 186
Driving systemsDriving and parking

downhill gradients. Take particular note of
this when driving a laden vehicle. 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 over-
heating and wearing too quickly.
Important safety notes If you fail to adapt your driving style, SPEED-
TRONIC can neither reduce the risk of an
accident nor override the laws of physics.
SPEEDTRONIC cannot take into account
road, weather or traffic conditions. SPEED-
TRONIC 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 stay-ing in lane.
If there is a change of drivers, advise the new
driver of the speed stored.
Variable SPEEDTRONIC General notes
:
To store the current speed or a higher
speed
; LIM indicator lamp
= To store the current speed and call up the
last stored speed
? To store the current speed or a lower
speed
A To switch between cruise control or
DISTRONIC PLUS and variable SPEED-
TRONIC
B To deactivate variable SPEEDTRONIC With the cruise control lever, you can operate
cruise control or DISTRONIC PLUS and vari-
able SPEEDTRONIC.
The LIM indicator lamp on the cruise control
lever indicates which system you have selec-
ted:
R LIM indicator lamp off: cruise control or
DISTRONIC PLUS is selected.
R LIM indicator lamp on: variable SPEED-
TRONIC is selected.
You can use the cruise control lever to limit
the speed to any speed above 30 km/ hwhile
the engine is running.
Selecting variable SPEEDTRONIC If there is a change of drivers, advise the new
driver of the limit speed stored.
X Check whether LIM indicator lamp :is on.
If it is on, variable SPEEDTRONIC is already
selected.
If it is not, press the cruise control lever in
the direction of arrow ;.
LIM indicator lamp :in the cruise control
lever is on. Variable SPEEDTRONIC is selec-
ted. Driving systems
189Driving and parking Z

R
drive slower than the stored speed without
kickdown
R set a new speed or
R call up the last speed stored again.
The SPEEDTRONIC passive
SPEEDTRONIC passive message in the
multifunction display disappears.
Deactivating variable SPEEDTRONIC
It is not possible to deactivate variable
SPEEDTRONIC by braking. There are several ways to deactivate variable
SPEEDTRONIC:
X Briefly press the cruise control lever for-
wards =.
or X Briefly press the cruise control lever in the
direction of arrow ;.
LIM indicator lamp :in the cruise control
lever goes out. Variable SPEEDTRONIC is
deactivated.
Cruise control or DISTRONIC PLUS is selec-
ted.
i The last speed stored is cleared when you
switch off the engine.
Permanent SPEEDTRONIC You can use the on-board computer to limit
the speed permanently to a value between
160 km/ h(e.g. for driving on winter tyres) and
the maximum speed (Y page 262).
Shortly before the stored speed is reached, it
appears in the multifunction display. Permanent SPEEDTRONIC remains active,
even if variable SPEEDTRONIC is deactivated.
You cannot exceed the stored limit speed,
even if you depress the accelerator pedal
beyond the pressure point (kickdown). 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 so that the set speed is not
exceeded.
Change into a lower gear in good time on long
and steep downhill gradients. Take particular
note of this when driving a laden vehicle. 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. Without your intervention,
DISTRONIC PLUS cannot prevent a collision.
An intermittent warning tone will then sound
and the distance warning lamp will light up in
the instrument cluster. Brake immediately to
increase the distance to the vehicle driving in
front, or take evasive action, provided it is
safe to do so.
DISTRONIC PLUS operates in the range
between 0 km/h and 200 km/h.
Do not use DISTRONIC PLUS while driving on roads with steep gradients. Driving systems
191Driving and parking Z

Useful information
i This Owner's Manual describes all mod-
els, series and optional equipment for your
vehicle that were available at the time of
going to press. National variations are pos- sible. Note that your vehicle may not be
equipped with all of the functions descri-
bed. This is also the case for systems and
functions relevant to safety.
i Read the information on qualified special-
ist workshops: (Y page 25). Important safety notes
G
WARNING
Operating the integrated information systems and communications equipment in the vehicle
while driving will distract you from traffic con-
ditions. You could then lose control of the
vehicle. There is a risk of an accident.
Only operate these devices if road traffic con-
ditions permit. If you are unsure about the
surrounding conditions, pull over to a safe
location and make entries only while the vehi-
cle 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 recognise function
restrictions 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. Otherwise, a vehicle that is not oper-
ating safely may cause an accident.
If the operating safety of the vehicle is not
guaranteed, stop the vehicle at once, paying
attention to road traffic conditions. Contact a
qualified specialist workshop.
For an overview, see the instrument panel
illustration (Y page 32). Displays and operation
Rev counter
! Do not drive in the overrevving range.
Doing so will damage the engine.
The red band in the rev counter indicates the engine's overrevving range.
The fuel supply is interrupted to protect the
engine when the red band is reached. Coolant temperature gauge
G
WARNING
If you open the bonnet while the engine is
overheating or while there is a fire in the
engine compartment, you could come into
contact with hot gases or other leaking ser-
vice products. There is a danger of injury.
Allow an overheating engine to cool down
before opening the bonnet. If there is a fire in the engine compartment, leave the bonnet
closed and notify the fire brigade.
The coolant temperature is shown in the rev
counter (Y page 32).
At high outside temperatures and when driv-
ing uphill, the coolant temperature may rise.
Under normal operating conditions and with
the specified coolant level, the coolant tem-
perature may rise to 124 †. 242
Displays and operationOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions #
See Owner's Manual See Owner's Manual The battery is not being charged.
A warning tone also sounds.
Possible causes:
R faulty alternator
R torn poly-V-belt
R a malfunction in the electronics
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
! Do not continue driving. The engine could otherwise overheat.
X Secure the vehicle to prevent it from rolling away (Y page 178).
X Consult a qualified specialist workshop. #
Stop vehicle See Stop vehicle See
Owner's Manual Owner's Manual The battery is no longer being charged and the battery charge level
is too low.
A warning tone also sounds.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 178).
X Observe the instructions in the #See Owner's Manual See Owner's Manual
display message.
X Consult a qualified specialist workshop. #
Start engine See Start engine See
Owner's Manual Owner's Manual The engine is off and the battery charge level is too low.
X Switch off electrical consumers that you do not need, such as
the rear window heating and interior lighting.
X Leave the engine running for a few minutes, or drive for a longer
distance.
The battery charges. Display
messages
283On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions 4
Check eng. oil Check eng. oil
lev. when next lev. when next
refuelling refuelling The engine oil level has dropped to the minimum level.
A warning tone also sounds.
X Check the oil level when next refuelling, at the latest
(Y page 338).
X If necessary, top up the engine oil (Y page 340).
X Have the engine checked at a qualified specialist workshop if the
engine oil needs topping up more often than usual.
! Avoid long journeys when there is too little coolant in the cool-
ing system. Otherwise the engine will be damaged.
Information on approved engine oils can be obtained from any
qualified specialist workshop or on the Internet at http://
bevo.mercedes-benz.co m.4
Add Add
1
1litre
litre engine
engine
oil
oil when
when next
next refu‐
refu‐
elling
elling The engine oil level has dropped to the minimum level.
X Check the oil level when next refuelling, at the latest
(Y page 338).
X If necessary, top up the engine oil (Y page 340).
X Have the engine checked at a qualified specialist workshop if the
engine oil needs topping up more often than usual.
! Avoid long journeys when there is too little coolant in the cool-
ing system. Otherwise the engine will be damaged.
Information on approved engine oils can be obtained from any
qualified specialist workshop or on the Internet at http://
bevo.mercedes-benz.com. 4
Engine oil level Engine oil level
Stop vehicle Stop vehicle
Switch engine off Switch engine off The engine oil level is too low. There is a risk of engine damage.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle to prevent it from rolling away (Y page 178).
X Check the engine oil level (Y page 338).
X If necessary, top up the engine oil (Y page 340).8
Reserve fuel level Reserve fuel level The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated if the fuel level
drops into the reserve range.
X Refuel at the nearest filling station. C C There is very little fuel in the fuel tank.
The auxiliary heating cannot be operated.
X Refuel at the nearest filling station without fail. 284
Display messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions M
M The bonnet is open. A warning tone also sounds.
G WARNING
The open bonnet may then block your view when the vehicle is in
motion.
There is a risk of an accident.
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 178).
X Close the bonnet. Active bonnet mal‐ Active bonnet mal‐
function See Own‐ function See Own‐
er's Manual er's Manual The active bonnet (pedestrian protection) is not active due to a
malfunction or because it has already been triggered.
X Visit a qualified specialist workshop. C C At least one door is open. A warning tone also sounds.
X Close all doors. _
Front left seat Front left seat
backrest not backrest not
locked locked
orFront
Front
right seat back‐
right seat back‐
rest not locked
rest not locked The driver's or front-passenger seat backrest is not engaged. A
warning tone also sounds.
X Push the backrest back until it engages. &
inoperative Bat‐ inoperative Bat‐
tery low tery low The on-board voltage is too low. The auxiliary heating (Y
page 148)
has switched itself off. The auxiliary heating cannot be switched
on.
X Drive for a considerable distance.
The battery charges. The auxiliary heating is operational again as
soon as the on-board electrical system voltage is sufficient. &
inoperative inoperative
Refuel
Refuel
vehicle
vehicle There is too little fuel in the fuel tank. The auxiliary heating cannot
be switched on (Y page 148).
X Refuel at the nearest filling station. &
inoperative See inoperative See
Owner's Man. Owner's Man. The auxiliary heating is temporarily malfunctioning or faulty.
X When the vehicle is on a level surface and the engine has cooled
down, make up to four attempts to switch on the auxiliary heat- ing, waiting several minutes between each attempt
(Y page 148).
X If the auxiliary heating does not switch on, consult a qualified
specialist workshop. Display
messages
297On-board computer and displays Z

Engine
Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ;
N
The yellow engine diagnostics warning lamp lights up while the engine is
running.
There may be a fault, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system
R in the fuel system
The emission limit values may be exceeded and the engine may be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified specialist work-
shop. 8
N
The yellow reserve fuel warning lamp is on while the engine is running.
The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated if the fuel level drops into the reserve range.
X Refuel at the nearest filling station. ?
N
The red coolant warning lamp lights up while the engine is running and the
coolant temperature gauge is at the start of the bar display.
The temperature sensor for the coolant temperature gauge is faulty.
The coolant temperature is no longer being monitored. There is a risk of engine
damage if the coolant temperature is too high.
X Stop the vehicle immediately, paying attention to road and traffic condi-
tions, and switch off the engine. Do not continue driving under any circum-
stances.
X Secure the vehicle against rolling away (Y page 178).
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
307On-board computer and displays Z