ignition MERCEDES-BENZ C-CLASS SALOON 2012 Workshop Manual

&
WARNING Risk of injury fromtouching
co mp onents under voltage
The ignition sy stem and the fuel injection
sy stem workunder high voltage. You could
re cei vean electric shoc k. #
Neverto uch co mponents of the ignition
sy stem or the fuel injection sy stem
when the ignition is switched on. &
WARNING Risk of burn s from hot com‐
ponent parts in the engine compartment
Cer tain component parts in the engine com‐
partment can be very hot, e.g. the engine,
th e cooler and parts of theex haust sy stem. #
Allow the engine tocool down and only
to uch co mponent parts described in
th efo llowing. &
WARNING Risk of injury from usingthe
windscreen wipers while the engine bon‐
net is open
When the engine bonn etis open, and the
windscreen wipers are set in motion, you can
be trapped bythe wiper linkage. #
Alw ays switch off the windscreen wip‐
ers and ignition before opening the
engine bonn et. *
NO
TEPlug-in hybrid #
Obser vethe no tes in the Supplement.
Yo u could otherwise failto recognise
dangers. Opens the bonnet
#
Torelease the bonn et, pull on handle 1. Maintenance and care
375
Internal use only

#
Drain off any excess engine oil that has been
added. Todo so, consult a qualified specialist
wo rkshop.
R For engine oil level turn on ignition #
Switch on the ignition tocheck the engine oil
le ve l.
R Engine oil level System inoperative : The oil
le ve l sensor is defective or not connecte d.#
Consult a qualified specialist workshop.
R Engine oil level System currently unavail. #
Close the bonn et.
To pping up engine oil &
WARNING Risk of burn s from hot com‐
ponent parts in the engine compartment
Cer tain component parts in the engine com‐
partment can be very hot, e.g. the engine,
th e cooler and parts of theex haust sy stem. #
Allow the engine tocool down and only
to uch co mponent parts described in
th efo llowing. &
WARNING Risk offire and injury from
engine oil
If engine oil comes into con tact with hot
component parts in the engine compart‐
ment, it may ignite. #
Make sure that no engine oil is spilled
next tothefiller opening. #
Allow the engine tocool off and thor‐
oughly clean the engine oil from compo‐
nent parts before starting theve hicle. *
NO
TEEngine damage causedbyan
incor rect oil filter, incor rect oil or addi‐
tives #
Do not use engine oils or oil filters
which do not cor respond tothe specifi‐
cations explicitly prescribed forthe
service inter vals. #
Follow the instructions on the service
inter val display forch anging the engine
oil and obser vethe prescribed change
inter vals. #
Do not use additives. *
NO
TEDama gecaused bytopping up too
much engine oil To
o much engine oil can damage the engine
or the catalytic con verter. #
Have excess engine oil remo ved at a
qu alified specialist workshop. %
Depending on driving style, theve hicle con‐
sumes up to0.8 litr e of oil pe r10 00 km. The
oil consum ption may be higher than this
when theve hicle is new or if you frequently
drive at high engine speeds. 378
Maintenance and care
Internal use only

-
oily products
R Do not use polish on matt decorative foil.
Po lishing will ha vethe ef fect of shining the
fo il-wrapped sur face.
R Do not treat matt or stru ctured deco rative
fo ils with wax.Pe rm anent stains may occur.
Sc ratches, cor rosive deposits, areas af fected by
cor rosion and damage caused byincor rect care
cannot al ways be comple tely re paired. In such
cases, visit a qualified specialist workshop.
Yo u can obtain more information on care and
cleaning products from the manufacturer.
In the case of foil-wrapped sur faces, optical dif‐
fe re nces may occur between the sur faces that
we renot pr otected bya decorative foil af ter
re moving a decorative foil.
% Have wo rkor repairs todecorative foils car‐
ri ed out at a qualified specialist workshop,
e.g. in a Mercedes-Benz Service Centre. Note
s on care of car parts &
WARNING Risk of entrapment if the
windscreen wipers are swit ched on while
th e windscreen is being cleaned
If th e windscreen wipers are set in motion
while you are cleaning the windscreen or
wiper blades, you can be trapped bythe
wiper arm. #
Alw ays switch off the windscreen wip‐
ers and the ignition before cleaning the
windscreen or wiper blades. &
WARNING Risk of burn s fromtheta il‐
pipe and tailpipe trims
The exhaust tailpipe and tailpipe trims can
become very hot. If you come into contact
with these parts of theve hicle, you could
burn yourself. #
Alw ays be particular lycareful around
th eta ilpipe and theta ilpipe trims and
supervise children especially closely in
th is area. #
Allow vehicle parts tocool down before
to uching them. To
avo id damage totheve hicle, obser vethe
no tes on cleaning and care of thefo llowing vehi‐
cle parts:
Wheels and rims
R Use wate r and acid-free alloy wheel cleaners.
R Do not use acidic alloy wheel cleaners to
re mo vebrake dust. This could damage wheel
bolts and brake components.
R Toavo id cor rosion of the brake disks and
brakepads, drive theve hicle for a few
minutes af ter cleaning before parking it. The
brake disks and brakepads warm up and dry
out.
Wi ndo ws
R Clean the windo wsinside and outside with a
damp clo thand with a cleaning agent recom‐
mended for Mercedes-Benz.
R Do not use dry clo ths or abrasive or sol vent-
based cleaning agents toclean the inside of
windo ws. 384
Maintenance and care
Internal use only

#
Remo vethe cap from valve 7 onthefa ulty
tyre. #
Screw filling hose 8onto valve 7. #
Insert plug 4into a 12V soc ket in your
ve hicle. #
Switch on the ignition. #
Press on and off switch 3onthe tyre infla‐
tion compressor.
The tyre inflation compressor is switched on.
The tyre is inflated. Fir st, tyre sealant is pum‐
ped into the tyre. The pressure may brief ly
ri se toappr oximately 500 kPa (5 bar/73 psi). Do not switch off
the ty reinflation compres‐
sor during this phase! #
Let the tyre inflation compressor runfo r a
maximum of ten minu tes.
The tyre should then ha veattained a tyre
pressure of at least 200 kPa (2.0 bar/
29 psi).
If tyre sealant leaks out, make sure you clean the
af fected area as quickly as possible. It is prefera‐
ble touse clean water.
If yo uge t tyre sealant on your clo thing, ha veit
cleaned as soon as possible with per chloroe thy‐
lene.
If, af terte n minutes, a tyre pressure of
200 kPa (2.0 bar/29 psi) has not been
attained: #
Switch off the tyre inflation compressor. #
Unscr ew thefilling hose from theva lve of the
defective tyre.
Please no tethat tyre sealant may leak out when
unscr ewing thefilling hose. #
Very slowly drive forw ards or reve rse appr ox‐
imately 10m. #
Pump up the tyre again.
Af ter a maximum of ten minu testh e tyre
pressure must be at least 200 kPa (2.0 bar/
29 psi). &
WARNING Risk of accident due tothe
specified tyre pressure not being
attained
If th e minimum tyre pressure is not reached
af te rth e specified time, the tyre is too badly
damaged. The tyre sealant cannot repair the
tyre in this ins tance.
The braking and driving characteristics may
be great lyimpaired. #
Do not continue driving. #
Consult a qualified specialist workshop. 394
Breakdown assis tance
Internal use only

Obser
vethefo llowing points during starting
assis tance and when charging the battery:
R Only use undamaged jump lead/charging
cables with a suf ficient cross-section and
insula tedte rm inal clamps.
R Non- insulated parts of thete rm inal clamps
must not come into con tact wi thother me tal
parts while the jump lead/charging cable is
connected tothe battery/jump-s tart connec‐
tion point.
R The jump lead/charging cable must not
come into contact wi thany parts which may
mo vewhen the engine is running.
R Alw ays make sure that nei ther you nor the
battery is elect rostatically charge d.
R Keep away from fire and naked flames.
R Do not lean overth e batter y.
Obser vethe additional following points when
ch arging the battery:
R Only use battery charge rs tested and
appr oved for Mercedes-Benz.
R Read the battery charge r's operating instruc‐
tions before charging the batter y. Obser
vethe additional following points during
st arting assis tance:
R Starting assis tance may only be pr ovided
using vehicles, batteries or other jump start
devices with a nominal voltage of 12V.
R The vehicles must not touch.
R Vehicles with a petrol engine: jump-start
th eve hicle only when the engine and exhaust
sy stem are cold. St
arting assi stance and charging the12 V
battery Preparing
starting assi stance/charging #
Secure theve hicle byapplying the electric
parking brake. #
Automatic transmission: shiftthe trans‐
mission toposition j. #
Manual transmission: shiftthe transmis‐
sion toneutral. #
Switch off the ignition and all electrical con‐
sumers. #
Open the bonn et. #
Fold co ver1 up in the direction of the
ar row. 400
Breakdown assis tance
Internal use only

#
Atowing dis tance of 50 km must not be
exc eeded. &
WARNING Risk of accident when towing
a ve hicle which is too heavy
If ano ther vehicle is tow- star ted or towed
aw ay, its weight must not exceed the permis‐
sible gross mass of your ow nve hicle, other‐
wise thefo llowing could occur:
R theto wing eye may become de tach ed.
R theve hicle/trailer combination may
swer veoreve nov erturn. #
If ano ther vehicle is tow- star ted or
to we daw ay, its weight must not exceed
th e permissible gross mass of your own
ve hicle. If a
vehicle must be tow- star ted or towe daw ay,
its permissible gross weight must not exceed the
permissible gross weight of theto wing vehicle. #
Information on the permissible gross mass of
th eve hicle can be found on theve hicle iden‐
tification plate (/ page 428). #
Vehicles with automatic transmission: do
not open the driver's door or front passenger
door, otherwise the automatic transmission
automatically shifts toposition j. #
Fittheto wing eye (/ page 406). #
Fasten theto w bar.
* NO
TEDama gedue toincor rect connec‐
tion of theto w bar #
Onlyconnect theto w rope or tow bar to
th eto wing eyes. #
Deactivate the automatic locking mechanism
(/ page 79). #
Do not activate the HOLD function. #
Deactivate tow- aw ay protection
(/ page 96). #
Deactivate Active Brake Assi st
( / page 210). #
Vehicles with automatic transmission:
shift the automatic transmission toposition
i. #
Release the electric parking brake. &
WARNING Risk of accident due tolimi‐
te d saf ety-re lated functions during the
to wing process
Saf ety-re lated functions are limited or no lon‐
ge rav ailable in thefo llowing situations:
R the ignition is switched off.
R the brake sy stem or po werst eering sys‐
te m is malfunctioning.
R the energy supply or the on-board electri‐
cal sy stem is malfunctioning.
When your vehicle is then towe daw ay, signif‐
icantly more ef fort may be requ ired tosteer
and brake than is norm allyrequ ired. #
Use a tow bar. #
Make sure that thesteering wheel can
mo vefreely before towing theve hicle
aw ay. 404
Breakdown assis tance
Internal use only

To
w starting theve hicle (eme rgency engine
st art) Ve
hicles with automatic transmission
* NO
TEDama getothe automatic trans‐
mission due to tow-starting The automatic transmission may be damaged
in
the process of tow- starting vehicles with
automatic transmission. #
Vehicles with automatic transmission
must not be tow- star ted. #
Vehicles with automatic transmission must
not be tow- star ted. Electrical fuses
Note
s on electrical fuses &
WARNING Risk of accident and inju ry
due to ov erloaded lines
If yo u manipulate or bridge a faulty fuse or if
yo ure place it with a fuse with a higher amperage,
the electric line could be overloa‐
ded.
This could result in a fire. #
Alw aysre place faulty fuses with speci‐
fi ed new fuses conta iningthe cor rect
amperage. *
NO
TEDama gedue toincor rect fuses Electrical components or sy
stems may be
damaged byincor rect fuses, or their func‐
tionality may be significant lyimpaired. #
Only use fuses that ha vebeen appr oved
by Mercedes-Benz and which ha vethe
cor rect fuse rating. Blown fuses mu
stbe replaced with fuses of the
same rating, which you can recognise bythe col‐
our and the labelling. The fuse ratings and fur‐
th er information tobe obser ved can be found in
th e fuse assignment diagram.
Fu se assignment diag ram: onthe fuse box in
th e boot (/ page 409). *
NO
TEDama geor malfunctions caused
by moisture Moisture may cause dama
getothe electrical
sy stem or cause it tomalfunction. #
When the fuse box is open, make sure
th at no moisture can enter the fuse
box. #
When closing the fuse box, make sure
th at the seal of the lid is positioned cor‐
re ctly on the fuse box. If
th e newly inser ted fuse also blo ws, ha vethe
cause traced and rectified at a qualified special‐
ist workshop.
Ensure thefo llowing before replacing a fuse:
R The vehicle is secured against rolling away.
R All electrical consumers are switched off.
R The ignition is switched off.
The electrical fuses are located in various fuse
bo xes:
R Fuse box in the engine compartment on the
driver's side (/ page 408) Breakdown assis
tance 407
Internal use only

R
Fuse box on the driver's side of the cockpit
(/ page 409)
R Fuse box in the front passenger foot we ll
(/ page 409)
R Fuse box in the boot on theright-hand side
of theve hicle, when vie wed in the direction
of tra vel (/ page 409) Opening and closing
the fuse box in the
engine compa rtment Re
quirements:
R A dry clo thand a sc rewdriver are available.
Obse rveth e no tes on electrical fuses
(/ page 407).
Opening &
WARNING Risk of injury from usingthe
windscreen wipers while the engine bon‐
net is open
When the engine bonn etis open, and the
windscreen wipers are set in motion, you can
be trapped bythe wiper linkage. #
Alw ays switch off the windscreen wip‐
ers and ignition before opening the
engine bonn et. #
Turn retaining clip 2on co ver1 aqu arter-
turn anti-clo ckwise. #
Fold co ver1 up in the direction of the
ar row. #
Remo veany existing moisture from the fuse
box using a dry clo th. #
Loosen scr ews3 and remo vefuse box lid
4 upwards.
Closing #
Che ckwhe ther the seal is positioned cor‐
re ctly in lid 4. 408
Breakdown assis tance
Internal use only

pressure
tothere commended cold tyre pressure
suitable forth e operating situation.
In most cases, the tyre pressure monitoring sys‐
te m will auto maticallyupdate the new refere nce
va lues af teryo u ha vechanged the tyre pressure.
Yo u can, ho wever,also update there fere nce val‐
ues byrestarting the tyre pressure monitoring
sy stem manually (/ page413).
Sy stem limits
The sy stem may be impaired or may not function
particular lyin thefo llowing situations:
R the tyre pressure has been set incor rectly
R sudden pressure loss caused byafo re ign
object penetrating the tyre, forex ample
R there is a malfunction caused byano ther
ra dio signal source
Checking the ty repressure with the tyre
pressure moni toring sy stem
Re quirements:
R The ignition is switched on. On-board computer:
4 Service 5
Tyres
One of thefo llowing displa ysappears:
R Cur rent tyre pressure and tyre temp erature
of the individual wheels: R
Tyre pressures will be displayed after a few
minutes of driving
R Tyre pressure monitor active: thete ach-in
process of the sy stem is not yet compl ete.
The tyre pressures are already being moni‐
to re d. #
Compare the tyre pressure with there com‐
mended tyre pressure forth e cur rent operat‐ ing condition (/
page 412). Observ ethe
no tes on tyre temp erature (/ page411).
% The values displa yed in the on-board com‐
puter may deviate from those of the tyre
pressure gauge as they referto sea le vel.At
high ele vations, the tyre pressure values
indicated bya pressure gauge are higher
th an those shown bythe on-board computer.
In this case, do not reduce the tyre pressure.
Re starting the ty repressure moni toring sys‐
tem
Re quirements:
R The recommended tyre pressure is cor rectly
set forth ere spective operating status on all
of the wheels (/ page411).
Re start the tyre pressure monitoring sy stem in
th efo llowing situations:
R The tyre pressure has changed.
R The wheels or tyres ha vebeen changed or
newly fitted. Wheels and tyres
413
Internal use only

R
brake fluid
R windsc reen washer fluid
R climate cont rol sy stem refrigerant
Only use products app rove dby Mercedes-Benz.
Damage caused bythe use of products that ha ve
not been appr oved is not co veredby the
Mercedes-Benz warranty or goodwill gestures.
The operating fluids appr ovedby Mercedes-Benz
can be identified bythefo llowing insc ript ions on
th e conta iner:
R MB- Freigabe (e.g. MB-Fr eigabe 229.51 )
R MB-Appr oval (e.g. MB-App rova l 229.51)
Fu rther information on appr oved operating flu‐
ids:
R inthe Mercedes-Benz Specifications for
Operating Fluids byentering the designation
- at https://be vo.mercedes-benz.com
- inthe Mercedes-Benz BeVo App
R at a qualified specialist workshop &
WARNING Risk offire or explosion from
fuel
Fu els are highly flammable. #
Fire, naked flames, smoking and crea‐
tion of spar ksmust be avoided. #
Swit choff the ignition and, if available,
th est ationary heater, before and while
re fuelling theve hicle. &
WARNING Risk of injury from fuels
Fu els are poisonous and hazardous to your
health. #
Do not swallow fuel or let it come into
contact with skin, eyes or clo thing. #
Do not inhale fuel vapour. #
Keep children away from fuel. #
Keep doors and windo wsclosed du ring
th ere fuelling process.
If yo u or other people come into contact with
fuel, obser vethefo llowing: #
Immediately rinse fuel off your skin with
soap and water. #
If fuel comes into contact with your
ey es, immediately rinse them thor‐
oughly with clean water.Seek medical
attention immediately. #
Ifyo u swallow fuel, seek medical atten‐
tion immediatel y.Do not induce vomit‐
ing. #
Change immediately out of clo thing that
has come into con tact with fuel. Flexible-fuel
vehicles can be refuelled with the
fo llowing fuel types:
R unleaded petrol
R E85 fuel
R a mixture of E85 fuel and unleaded petrol
Flexible-fuel vehicles can be identified bythe
Ethanol up toE85 sticke r on the inside of the
fuel filler flap.
Depending on the count ry,th e fuels you can use
in your vehicle may dif fer from the information in
th e Owner's Manual. The fuels that ha vebeen Te
ch nical da ta431
Internal use only