heating MERCEDES-BENZ C-CLASS SALOON 2014 Service Manual

Problem
Possible causes/consequences and
M
MSolutions Vehicles with a petrol
engine:
The engine is not run-
ning smoothly and is
misfiring. There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
X Only depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic con-
verter and damage it.
X Have the cause rectified immediately at a qualified specialist
workshop. The coolant tempera-
ture display is showing
more than 120 †. A
display message may
also appear in the mul-
tifunction display and a warning tone may
sound. The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.
X Stop as soon as possible and allow the engine and the coolant to
cool down.
X Check the coolant level (Y page 393). Observe the warning
notes as you do so and top up the coolant if necessary. If the coolant level is correct, the engine radiator fan may be faulty.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X If the coolant temperature is below 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in
mountainous terrain and stop-start traffic. Manual transmission
Gear lever
! Only engage gear when the clutch pedal is
depressed.
! When shifting between
5thand 6thgear,
you should always push the gear lever all
the way to the right. Otherwise, you could
shift unintentionally into 3rdor4th gear
and damage the transmission.
If you shift down at too high a speed (trans-
mission braking), this can cause the engine to overrev, leading to engine damage.
Do not use the clutch bite point to keep the
vehicle stationary on uphill gradients.
There is otherwise a risk of damaging the
clutch.
! On long and steep downhill gradients,
especially if the vehicle is laden or towing a trailer, you must shift into gear
1, 2or3in
good time. This uses the engine's braking
effect. This relieves the load on the brake
system and prevents the brakes from over- heating and wearing too quickly. k
Reverse gear
1 -6
Forward gears 190
Manual transmissionDriving and parking

Shifting to neutral N
X
Depress the clutch pedal fully.
X Move the gear lever to position N:. Engaging reverse gear
! Only shift into reverse gear
Rwhen the
vehicle is stationary. Otherwise, you could
damage the transmission.
X Move the gear lever firmly to the left,
beyond the point of resistance, then for-
wards.
The ECO start/stop function is not available
when reverse gear is engaged. For further
information on the ECO start/stop function;
see (Y page 186). Gearshift recommendation
The gearshift recommendations assist you in
adopting an economical driving style. The rec- ommended gear is shown in the multifunction
display.
X Shift gear according to gearshift recom-
mendation :when shown in the multi-
function display of the instrument cluster. C 180 BlueEFFICIENCY Edition:
in drive
program Ethe accelerator pedal also trans-
mits double pulses. Additional information
for drive programs (Y page 192). AGILITY SELECT switch
Use the AGILITY SELECT switch to change the drive program. Depending on the drive pro-
gram selected, the following vehicle charac-
teristics will change:
R the drive (engine and transmission man-
agement)
R the suspension
R the steering
R the availability of the ECO start/stop func-
tion (Y page 186)
R the climate control settings
- THERMATIC (Y page 153)
- THERMOTRONIC (Y page 156)
R the rear window heating operation period
(Y page 164)
R the performance of the seat heating
(Y page 123)
If the ignition is switched off for less than four hours, the previously selected drive program
is activated when the engine is next started. If
the ignition is switched off for more than four hours, drive program Cis activated when the
engine is next started. Manual transmission
191Driving and parking Z

X
Push AGILITY SELECT switch :up or down
until the desired drive program is selected. The selected drive program appears in the
multifunction display. After five seconds
the display goes out and the status icon of
the selected drive program appears.
In addition, the current drive program set-
tings are displayed in the Audio 20/
COMAND Online display.
Available drive programs: I
Individual Individual settings
S+
Sport Plus Extremely sporty driving
characteristics
S
Sport Sporty driving character-
istics
C
Comfort Comfortable and econom-
ical driving characteristics E
Eco Particularly economical
driving characteristics
Additional information for drive programs
(Y page 192). Drive programs
Drive program I (Individual) In drive program
Ithe following properties of
the drive program can be selected:
R the drive (engine and transmission man-
agement)
R the suspension
R the steering
R C 180 BlueTEC BlueEFFICIENCY Edition:
availability of the economical accelerator
pedal
Information about the selection of drive pro-
gram Iwith COMAND Online or Audio 20 can
be found in the Digital Owner's Manual. Drive program S+ (Sport Plus) Drive program
S+is characterised by the fol-
lowing:
R the vehicle exhibits extremely sporty driv-
ing characteristics
R the suspension exhibits particularly stiff
springing and damping settings (vehicles
with AIRMATIC)
R the ECO start/stop function is not available
Drive program S (Sport) Drive program
Sis characterised by the fol-
lowing:
R the vehicle exhibits sporty driving charac-
teristics
R the suspension exhibits stiff springing and
damping settings (vehicles with AIRMATIC)
Drive program C (Comfort) Drive program
Cis characterised by the fol-
lowing:
R the vehicle delivers comfortable, economi-
cal driving characteristics.
R increased sensitivity. This improves driving
stability on slippery road surfaces, for
example.
Drive program E (Eco) Drive program
Eis characterised by the fol-
lowing:
R the vehicle exhibits comfortable, economi-
cal driving characteristics.
R increased sensitivity. This improves driving
stability on slippery road surfaces, for
example.
R the performance of the air-conditioning and
heating systems are reduced. 192
Manual transmissionDriving and parking

This also applies if cruise control,
DISTRONIC PLUS or SPEEDTRONIC are
activated.
AGILITY SELECT switch
Use the AGILITY SELECT switch to change the drive program. Depending on the drive pro-
gram selected, the following vehicle charac-
teristics will change:
R the drive (engine and transmission man-
agement)
R the suspension
R the steering
R the availability of the ECO start/stop func-
tion (Y page 186)
R the climate control settings
- THERMATIC (Y page 153)
- THERMOTRONIC (Y page 156)
R the rear window heating operation period
(Y page 164)
R the performance of the seat heating
(Y page 123)
If the ignition is switched off for less than four hours, the previously selected drive program
is activated when the engine is next started. If
the ignition is switched off for more than four hours, drive program Cis activated when the
engine is next started. X
Push AGILITY SELECT switch :up or down
until the desired drive program is selected. The selected drive program appears in the
multifunction display. After five seconds the display goes out and the status icon of
the selected drive program appears.
In addition, the current drive program set-
tings are displayed in the Audio 20/
COMAND Online display.
Available drive programs: I
Individual Individual settings
S+
Sport Plus Extremely sporty driving
characteristics
S
Sport Sporty driving character-
istics
C
Comfort Comfortable and econom-
ical driving characteristics E
Eco Particularly economical
driving characteristics
Additional information for drive programs
(Y page 197).
Using the steering wheel gearshift paddles,
you can temporarily change gear yourself.
Further information on the manual drive pro-
gram (Y page 198). Drive programs
Drive program I (Individual) In drive program
Ithe following properties of
the drive program can be selected:
R the drive (engine and transmission man-
agement)
R the suspension
R the steering
To permanently select the gears in the drive
program Iusing the steering wheel paddles,
select the permanent manual gearshift pro-
gram.
Information about the selection of drive pro-
gram Iwith COMAND Online or Audio 20 can
be found in the Digital Owner's Manual. Automatic transmission
197Driving and parking Z

Drive program S+ (Sport Plus)
Drive program
S+is characterised by the fol-
lowing:
R the vehicle exhibits extremely sporty driv-
ing characteristics
R the vehicle pulls away in first gear
R the automatic transmission shifting up
later
R as a result of the later automatic transmis-
sion shift points, the fuel consumption pos-sibly being higher
R the suspension exhibits particularly stiff
springing and damping settings (vehicles
with AIRMATIC)
R the ECO start/stop function is not available
Drive program S (Sport) Drive program
Sis characterised by the fol-
lowing:
R the vehicle exhibits sporty driving charac-
teristics
R the vehicle pulls away in first gear
R the automatic transmission shifting up
later
R as a result of the later automatic transmis-
sion shift points, the fuel consumption pos-sibly being higher
R the suspension exhibits stiff springing and
damping settings (vehicles with AIRMATIC)
Drive program C (Comfort) Drive program
Cis characterised by the fol-
lowing:
R the vehicle delivers comfortable, economi-
cal driving characteristics.
R the vehicle pulling away more gently in
forward and reverse gears unless the accel- erator pedal is depressed fully.
R increased sensitivity. This improves driving
stability on slippery road surfaces, for
example.
R optimal fuel consumption resulting from
the automatic transmission shifting up sooner. The vehicle is driven in the low
engine speed range and the wheels are less
likely to spin.
Drive program E (Eco) Drive program
Eis characterised by the fol-
lowing:
R the vehicle exhibits comfortable, economi-
cal driving characteristics.
R the vehicle pulling away more gently in
forward and reverse gears unless the accel-
erator pedal is depressed fully.
R increased sensitivity. This improves driving
stability on slippery road surfaces, for
example.
R optimal fuel consumption resulting from
the automatic transmission shifting up
sooner. The vehicle is driven in the low
engine speed range and the wheels are less likely to spin.
R during deceleration, the engine is discon-
nected from the drive train. The vehicle
uses kinetic energy and consumes less fuel
(overrun mode).
R the performance of the air-conditioning and
heating systems are reduced. Manual gearshifting
General notes :
Left steering wheel gearshift paddle:
shifts down
; Right steering wheel gearshift paddle:
shifts up 198
Automatic transmissionDriving and pa
rking

Problems with the transmission
Problem
Possible causes/consequences and
M
MSolutions The transmission has
problems shifting gear. The transmission is losing oil.
X Have the transmission checked at a qualified specialist work-
shop immediately. The acceleration ability
is deteriorating.
The transmission no
longer changes gear. The transmission is in emergency mode.
It is only possible to shift into
secondgear and reverse gear.
X Stop.
X Shift the transmission to position P.
X Switch off the engine.
X Wait at least ten seconds before restarting the engine.
X Shift the transmission to position Dor R.
If D is selected, the transmission shifts into secondgear; ifRis
selected, the transmission shifts into reverse gear.
X Have the transmission checked at a qualified specialist work-
shop immediately. Problems with hybrid operation (Y
page 282).Transfer case
This section only applies to vehicles with all-
wheel drive (4MATIC). The front and rear
axles are constantly driven.
! Performance tests may only be carried
out on a two-axle roller dynamometer. Oth-
erwise, the braking system or the transfer
case could be damaged. Contact a qualified
specialist workshop for more information
on performance tests.
! Since ESP ®
engages automatically, the
ignition must be switched off (the key or
Start/Stop button must be in position 0or
1) if:
R the electric parking brake is being tested
using a brake dynamometer.
R the vehicle is being towed with only one
axle raised (not permitted for vehicles
with 4MATIC).
The brake system could otherwise be dam-
aged. !
Vehicles with 4MATIC must not be towed
with the front or rear axle raised; otherwise,
the transmission may be damaged. Refuelling
Important safety notes
G
WARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and explo-
sion.
You must avoid fire, naked flames, creating
sparks and smoking. Switch off the engine
and, if applicable, the auxiliary heating before refuelling. G
WARNING
Fuels are poisonous and hazardous to health. There is a danger of injury.
Do not swallow fuel or let it come into contact
with skin, eyes or clothing. Do not inhale fuel 200
RefuellingDriving and parking

time, the driver has adopted the most eco-
nomical driving style for the selected settings
and prevailing conditions. The ECO display
border lights up.
The ECO display does not indicate the actual fuel consumption. The additionally achieved
range displayed under Bonus fr. start Bonus fr. start
does not indicate a fixed consumption reduc-
tion.
In addition to driving style, the actual con-
sumption is affected by other factors, such
as:
R load
R tyre pressure
R cold start
R choice of route
R the use of electrical consumers
These factors are not included in the ECO dis-
play.
An economical driving style involves driving at a moderate engine speed.
To achieve a higher value in the categories
"acceleration" and "smooth driving":
R observe the gearshift recommendation
R drive the vehicle in drive program E(vehi-
cles with the AGILITY SELECT switch)
On long journeys at a constant speed, e.g. on the motorway, only the outer area for "con-
stant" will change.
The ECO display summarises 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. Dur- ing a prolonged driving time, these changes
are smaller. For more marked changes, per-
form a manual rest (Y page 299).
Further information on the ECO display
(Y page 298). Brakes
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.
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 and
when towing a trailer.
This also applies if cruise control, DISTRONIC
PLUS or SPEEDTRONIC are activated.
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. Driving
tips
213Driving an d parking Z

R
avoid sudden steering movements
R brake carefully
Driving on flooded roads !
Bear in mind that vehicles travelling in
front or in the opposite direction create
waves. This may cause the maximum per-
missible water depth to be exceeded.
These notes must be observed under all
circumstances. You could otherwise dam-
age the engine, the electronics or the trans- mission.
If you must drive on stretches of road on
which water has collected, please bear in
mind that:
R the water level, in the case of still water,
may not exceed a maximum point of the
lower edge of the vehicle body
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 Vehicles with manual transmission:
shift to neutral.
X Vehicles with automatic transmission:
shift 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. The vehicle could skid if you fail to adapt your
driving style. Always adapt your driving style
and drive at a speed to suit the prevailing
weather conditions.
You should pay special attention to road con-
ditions when temperatures are around the
freezing point.
Further information on driving with snow
chains (Y page 431).
Further information on driving with summer
tyres (Y page 430).
Observe the notes in the "Winter operation"
section (Y page 430). Driving tips
215Driving and parking Z

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 thevehicle occupants and that of other road
users.
Further information on driving safety systems
(Y page 74). 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 and when
towing a trailer. 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 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 to 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. 216
Driving syste
msDriving and parking

Cruise control is automatically deactivated if:
R you apply the electric parking brake
R you are driving at less than 30 km/h
R ESP ®
intervenes or you deactivate ESP ®
R while driving a vehicle with manual trans-
mission, you shift into neutral or depress
the clutch pedal for longer than six seconds
R on vehicles with manual transmission, you
shift to a gear that is too high, and as a
result the engine speed is too low
R on vehicles with automatic transmission,
you shift into position Nwhile 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 The last speed stored is cleared when you
switch off the engine. SPEEDTRONIC
General notes SPEEDTRONIC brakes automatically so that
you do not exceed 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.
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. You can set a variable or permanent limit
speed:
R variable for speed limits, e.g. in built-up
areas
R permanent for long-term speed restric-
tions, e.g. when driving with winter tyres
fitted (Y page 221)
i The speed indicated in the speedometer
may differ slightly from the limit speed
stored.
Variable SPEEDTRONIC General notes
:
To store the current speed or a higher
speed
; LIM indicator lamp
= To store the current speed and calling 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. Driving systems
219Driving and parking Z