check engine MERCEDES-BENZ C-Class SEDAN 2015 W205 Service Manual

Displaying service messages
X Switch on the ignition.
X Use 00E2 on the steering wheel to call up
the list of menus.
X Press the 0063or0064 button on the steer-
ing wheel to select the Service
Service menu and
press 0076to confirm.
X Press the 0063or0064 button on the steer-
ing wheel to select the ASSYST PLUS
ASSYST PLUS sub-
menu and press 0076to confirm.
The service due date appears in the multi-
function display. Information about Service
Resetting the ASSYST PLUS service
interval display !
If the ASSYST PLUS service interval dis-
play has been inadvertently reset, this set-
ting can be corrected at a qualified special-
ist workshop.
Have service work carried out as described in the Maintenance Booklet. This may oth-
erwise lead to increased wear and damage
to the major assemblies or the vehicle.
A qualified specialist workshop, e.g. an
authorized Mercedes-Benz Center, will reset
the ASSYST PLUS service interval display
after the service work has been carried out.
You can also obtain further information on
maintenance work, for example.
Special service requirements The specified maintenance interval takes only
the normal operation of the vehicle into
account. Under arduous operating conditions
or increased load on the vehicle, mainte-
nance work must be carried out more fre-
quently, for example:
R regular city driving with frequent intermedi-
ate stops
R if the vehicle is primarily used to travel
short distances R
use in mountainous terrain or on poor road
surfaces
R if the engine is often left idling for long peri-
ods
Under these or similar conditions, have, for
example, the air filter, engine oil and oil filter
replaced or changed more frequently. Under
arduous operating conditions, the tires must
be checked more often. Further information
can be obtained at a qualified specialist work- shop, e.g. an authorized Mercedes-Benz Cen-
ter.
Driving abroad An extensive Mercedes-Benz Service network
is also available in other countries. You can
obtain further information from any author-
ized Mercedes-Benz Center. Care
General notes
H
Environmental note
Dispose of empty packaging and cleaning
cloths in an environmentally responsible man- ner.
! For cleaning your vehicle, do not use any
of the following:
R dry, rough or hard cloths
R abrasive cleaning agents
R solvents
R cleaning agents containing solvents
Do not scrub.
Do not touch the surfaces or protective
films with hard objects, e.g. a ring or ice
scraper. You could otherwise scratch or
damage the surfaces and protective film.
! Do not park the vehicle for an extended
period straight after cleaning it, particularly after having cleaned the wheels with wheel
cleaner. Wheel cleaners could cause
increased corrosion of the brake discs and brake pads/linings. For this reason, you Care
329Maintenance and care Z

Flat tire
Preparing the vehicle
Your vehicle may be equipped with: R MOExtended tires (tires with run-flat prop-
erties) (Y page 341)
Vehicle preparation is not necessary on
vehicles with MOExtended tires
R a TIREFIT kit (Y page 340)
Information on changing/mounting a wheel
(Y page 381).
X Stop the vehicle on solid, non-slippery and
level ground, as far away as possible from
traffic.
X Switch on the hazard warning lamps.
X Secure the vehicle against rolling away
(Y page 174).
X If possible, bring the front wheels into the
straight-ahead position.
X Switch off the engine.
X Remove the SmartKey from the ignition
lock.
or, in vehicles with KEYLESS-GO start-func-
tion or KEYLESS‑GO
X Open the driver's door.
The on-board electronics now have status
0. This is the same as the SmartKey having
been removed.
X Remove the Start/Stop button from the
ignition lock (Y page 157).
X All occupants must get out of the vehicle.
Make sure that they are not endangered as
they do so.
X Make sure that no one is near the danger
area while a wheel is being changed. Any-
one who is not directly assisting in the
wheel change should, for example, stand
behind the barrier.
X Get out of the vehicle. Pay attention to traf-
fic conditions when doing so.
X Close the driver's door. MOExtended tires (tires with run-flat
properties)
General notes With MOExtended tires (tires with run flat
characteristics), you can continue to drive
your vehicle even if there is a total loss of
pressure in one or more tires. The affected
tire must not show any clearly visible damage.
You can recognize MOExtended tires by the
MOExtended marking which appears on the
sidewall of the tire. You will find this marking next to the tire size designation, the load-
bearing capacity and the speed index
(Y page 375).
MOExtended tires may only be used in con-
junction with an active tire pressure loss
warning system or with an active tire pressure
monitor.
If the pressure loss warning message
appears in the multifunction display:
R Observe the instructions in the display
messages (Y page 277).
R Check the tire for damage.
R If driving on, observe the following notes.
The maximum driving distance is approx-
imately 50 mile s(80 km) when the vehicle is
partially laden and approximately 18 miles
(30 km) when the vehicle is fully laden.
In addition to the vehicle load, the driving dis- tance possible depends upon:
R Speed
R Road condition
R Outside temperature
The driving distance possible in run-flat mode may be reduced by extreme driving condi-
tions/maneuvers, or it can be increased
through a moderate style of driving.
The maximum permissible distance which
can be driven in run-flat mode is counted fromthe moment the tire pressure loss warning
appears in the multifunction display.
You must not exceed a maximum speed of
50 mph (80 km/h). Flat tire
341Roadside Assistance

R
if you push or pull the battery across the
carpet or other synthetic materials
R if you wipe the battery with a cloth G
WARNING
During the charging process, a battery produ- ces hydrogen gas. If a short circuit occurs or
sparks are created, the hydrogen gas can
ignite. There is a risk of an explosion.
R Make sure that the positive terminal of a
connected battery does not come into con- tact with vehicle parts.
R Never place metal objects or tools on a bat-
tery.
R It is important that you observe the descri-
bed order of the battery terminals when
connecting and disconnecting a battery.
R When jump-starting, make sure that the
battery poles with identical polarity are
connected.
R It is particularly important to observe the
described order when connecting and dis-
connecting the jumper cables.
R Never connect or disconnect the battery
terminals while the engine is running. G
WARNING
Battery acid is caustic. There is a risk of injury. Avoid contact with the skin, eyes or clothing.
Do not inhale any battery gases. Do not lean
over the battery. Keep children away from
batteries. Wash battery acid immediately with water and seek medical attention. H
Environmental note Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separately
and recycled to protect the
environment. Dispose of batteries in an
environmentally friendly
manner. Take discharged
batteries to a qualified spe- cialist workshop or a special
collection point for used bat-
teries.
! Have the battery checked regularly at a
qualified specialist workshop.
Observe the service intervals in the Main-
tenance Booklet or contact a qualified spe-
cialist workshop for more information.
! You should have all work involving the
battery carried out at a qualified specialist
workshop. In the exceptional case that it is
necessary for you to disconnect the battery yourself, make sure that:
R secure the vehicle to prevent it from roll-
ing away.
R you switch off the engine and remove the
SmartKey. Make sure the ignition is
switched off. Check that all the indicator lamps in the instrument cluster are off.
Otherwise, electronic components, such
as the alternator, may be damaged.
R you first remove the negative terminal
clamp and then the positive terminal
clamp. Never swap the terminal clamps.
Otherwise, the vehicle's electronic sys-
tem may be damaged.
R the transmission is locked in position P
after disconnecting the battery. The vehi-
cle is secured against rolling away. You
can then no longer move the vehicle.
The battery and the cover of the positive
terminal clamp must be installed securely
during operation.
Comply with safety precautions and take pro-
tective measures when handling batteries. Risk of explosion.
Fire, open flames and smoking are
prohibited when handling the bat-
tery. Avoid creating sparks. 346
Battery (vehicle)Roadside Assistance

Battery acid is caustic. Avoid con-
tact with skin, eyes or clothing.
Wear suitable protective clothing,
especially gloves, apron and face-
guard.
Rinse any acid spills immediately
with clear water. Contact a physi-
cian if necessary. Wear eye protection.
Keep children away.
Observe this Operator's Manual.
For safety reasons, Mercedes-Benz recom-
mends that you only use batteries which have been tested and approved for your vehicle by
Mercedes-Benz. These batteries provide
increased impact protection to prevent vehi-
cle occupants from suffering acid burns
should the battery be damaged in the event of
an accident.
In order for the battery to achieve the maxi-
mum possible service life, it must always be
sufficiently charged.
The vehicle battery, like other batteries, can
discharge over time if you do not use the
vehicle. In this case, have the battery discon- nected at a qualified specialist workshop. You
can also charge the battery with a charger
recommended by Mercedes-Benz. Contact a
qualified specialist workshop for further infor- mation.
Have the battery condition of charge checked
more frequently if you use the vehicle mainly
for short trips or if you leave it standing idle
for a lengthy period. Consult a qualified spe-
cialist workshop if you wish to leave your
vehicle parked for a long period of time.
Remove the SmartKey if you park the vehicle and do not require any electrical consumers. The vehicle will then use very little energy,
thus conserving battery power. Charging the battery
G
WARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, open flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over a battery. G
WARNING
Battery acid is caustic. There is a risk of injury. Avoid contact with the skin, eyes or clothing.
Do not inhale any battery gases. Do not lean
over the battery. Keep children away from
batteries. Wash battery acid immediately with water and seek medical attention. G
WARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing the vehicle or charging the battery, gases can escape from the battery. There is a risk of
an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
! Only use battery chargers with a maxi-
mum charging voltage of 14.8 V.
! Only
charge the battery using the jump-
starting connection point.
The jump-starting connection point is in the
engine compartment (Y page 349).
X Open the hood.
X Connect the battery charger to the positive
terminal and ground point in the same
order as when connecting the donor bat-
tery in the jump-starting procedure
(Y page 349). Battery (vehicle)
347Roadside Assistance Z

Jump-starting
For the jump-starting procedure, use only the jump-starting connection point, consisting of a positive terminal and a ground point, in the engine compartment. G
WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with the skin, eyes or clothing. Do not inhale any battery gases. Do not lean over the battery. Keep children away from batteries. Wash battery acid immediately with water and seek
medical attention. G
WARNING
During charging and jump-starting, explosive gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, open flames, creating sparks and smoking. Ensure there is sufficient ven-
tilation while charging and jump-starting. Do not lean over a battery. G
WARNING
During the charging process, a battery produces hydrogen gas. If a short circuit occurs or sparks
are created, the hydrogen gas can ignite. There is a risk of an explosion.
R Make sure that the positive terminal of a connected battery does not come into contact with
vehicle parts.
R Never place metal objects or tools on a battery.
R It is important that you observe the described order of the battery terminals when connecting
and disconnecting a battery.
R When jump-starting, make sure that the battery poles with identical polarity are connected.
R It is particularly important to observe the described order when connecting and disconnecting
the jumper cables.
R Never connect or disconnect the battery terminals while the engine is running. G
WARNING
A discharged battery can freeze at temperatures below freezing point. When jump-starting the
vehicle or charging the battery, gases can escape from the battery. There is a risk of an explosion.
Allow the frozen battery to thaw out before charging it or jump-starting.
! Avoid repeated and lengthy starting attempts. Otherwise, the catalytic converter could be
damaged by the non-combusted fuel.
If, at low temperatures, the indicator lamps/warning lamps in the instrument cluster do not
light up, it is highly likely that the discharged battery has frozen. In this case, you may neither
charge the battery nor jump-start the vehicle. The service life of a thawed-out battery may be
shorter. The starting characteristics can be impaired, particularly at low temperatures. Have
the thawed-out battery checked at a qualified specialist workshop. Jump-starting
349Roadside Assistance Z

X
Slide cover 0083of positive terminal 0043in the direction of the arrow.
X Connect positive terminal 0043on your vehicle to positive terminal 0044of donor battery 0084
using the jumper cable. Always begin with positive terminal 0043on your own vehicle first.
X Start the engine of the donor vehicle and run it at idling speed.
X Connect negative terminal 0087of donor battery 0084to ground point 0085of your vehicle using
the jumper cable, connecting the jumper cable to donor battery 0084first.
X Start the engine.
X Before disconnecting the jumper cables, let the engine run for several minutes.
X First, remove the jumper cables from ground point 0085and negative terminal 0087, then from
positive clamp 0043and positive terminal 0044. Begin each time at the contacts on your own
vehicle first.
X Close cover 0083of positive clamp 0043after removing the jumper cables.
X Have the battery checked at a qualified specialist workshop.
Jump-starting is not considered to be a normal operating condition.
i Jumper cables and further information regarding jump-starting can be obtained at any
qualified specialist workshop. Towing and tow-starting
Important safety notes
G
WARNING
Functions relevant to safety are restricted or
no longer available if:
R the engine is not running.
R the brake system or the power steering is
malfunctioning.
R there is a malfunction in the voltage supply
or the vehicle's electrical system.
If your vehicle is being towed, much more
force may be necessary to steer or brake.
There is a risk of an accident.
In such cases, use a tow bar. Before towing,
make sure that the steering moves freely. G
WARNING
You can no longer steer the vehicle if the
steering wheel lock has been engaged. There is a risk of an accident.
Always switch off the ignition when towing the
vehicle with a tow cable or a tow bar. G
WARNING
When towing or tow-starting another vehicle
and its weight is greater than the permissible gross weight of your vehicle, the:
R the towing eye could detach itself
R the vehicle/trailer combination could roll-
over.
There is a risk of an accident.
When towing or tow-starting another vehicle,
its weight should not be greater than the per- missible gross weight of your vehicle.
! When COLLISION PREVENTION ASSIST
PLUS, DISTRONIC PLUS or the HOLD func- tion is activated, the vehicle brakes auto-
matically in certain situations. To avoid
damage to the vehicle, deactivate these
systems in the following or similar situa-
tions:
R when towing the vehicle
R in the car wash
! Make sure that the electric parking brake
is released. If the electric parking brake is
faulty, visit a qualified specialist workshop. Towing and tow-starting
351Roadside Assistance Z

Brake fluid
G
WARNING
The brake fluid constantly absorbs moisture
from the air. This lowers the boiling point of
the brake fluid. If the boiling point of the brake fluid is too low, vapor pockets may form in the brake system when the brakes are applied
hard. This would impair braking efficiency.
There is a risk of an accident.
You should have the brake fluid renewed at
the specified intervals.
When handling brake fluid, observe the
important safety notes on service products
(Y page 397).
The brake fluid change intervals can be found
in the Maintenance Booklet.
Only use brake fluid approved by Mercedes-
Benz according to MB Approval 331.0.
Information about approved brake fluid can
be obtained at any qualified specialist work-
shop or on the Internet at
http://bevo.mercedes-benz.co m.
i Have the brake fluid regularly replaced at
a qualified specialist workshop 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 Service Products, MB BeVo 310.1, e.g.
on the Internet at
http://bevo.mercedes-benz.com. Or con-
tact 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
replacement confirmed in the Maintenance Booklet.
The coolant is a mixture of water and anti-
freeze/corrosion inhibitor. It performs the
following 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 cool-
ant 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 no t exceed 55% (antifreeze protection
down to -49 ‡ [-45 †]). Otherwise, heat
will not be dissipated as effectively.
Mercedes-Benz recommends an antifreeze/
corrosion inhibitor concentrate in accord-
ance with MB Specifications for Service Prod- ucts 310.1.
The coolant is checked with every mainte-
nance interval at a qualified specialist work-
shop.
i When the vehicle is first delivered, it is fil-
led with a coolant mixture that ensures Service products and filling capacities
401Technical data Z

adequate antifreeze and corrosion protec-
tion.
i The coolant is checked with every main-
tenance interval at a qualified specialist
workshop.
Filling capacities Model Capacity
C 300
C 300 4MATIC
8.5 US qt (8.0 l)
C 400 4MATIC
11.5 US qt (10.9 l)
i
Use MB 325.0 or MB 326.0 corrosion
inhibitor/antifreeze. Windshield/headlamp cleaning sys-
tem
Important safety notes G
WARNING
Windshield washer concentrate could ignite if it comes into contact with hot engine compo-
nents or the exhaust system. There is a risk of
fire and injury.
Make sure that no windshield washer con-
centrate is spilled next to the filler neck.
! Only use washer fluid that is suitable for
plastic lamp lenses, e.g. MB SummerFit or
MB WinterFit. Unsuitable washer fluid
could damage the plastic lenses of the
headlamps.
! Do not add distilled or de-ionized water to
the washer fluid container. Otherwise, the
level sensor may be damaged.
! Only MB SummerFit and MB WinterFit
washer fluid should be mixed together. The spray nozzles may otherwise become
blocked. At temperatures above freezing:
X Fill the washer fluid reservoir with a mixture
of water and windshield washer fluid, e.g.
MB SummerFit.
Add 1 part MB SummerFit to 100 parts water.
At temperatures below freezing:
X Fill the washer fluid reservoir with a mixture
of water and washer fluid, e.g. MB Winter-
Fit.
For the correct mixing ratio refer to the
information on the antifreeze reservoir.
i Add windshield washer fluid, e.g. MB
SummerFit or MB WinterFit, to the washer
fluid all year round. Climate control system refrigerant
Important safety notes The climate control system of your vehicle is
filled with refrigerant R‑
134a.
The instruction label regarding the refrigerant type used can be found on the radiator cross
member.
! Only the refrigerant R‑134a and the PAG
oil approved by Mercedes-Benz may be
used. The approved PAG oil may not be
mixed with any other PAG oil that is not
approved for R-134a refrigerant. Other-
wise, the climate control system may be
damaged.
Service work, such as topping up refrigerant
or replacing components, may only be carried out by a qualified specialist workshop. All
applicable regulations must be adhered to,
SAE standard J639 included.
Always have work on the climate control sys-
tem carried out at a qualified specialist work-
shop. 402
Service products and filling capacitiesTechnical data