2012 MERCEDES-BENZ CLS COUPE check engine light

Problem Possible causes/consequences and
M Solutions
The engine cannot be
started using the key. the on-board voltage is too low.
X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 318).
or
X Jump-start the vehicle (Y page 319).
or
X Consult aqualified specialist workshop. The engine cannot be
started using KEYLESS-
GO. The key is in the
vehicle. Ad
oor is open. Therefore, the key cannot be detected as easily.
X Close the door and try to start the vehicle again. There is interferenc
efrom apowerful source of radio waves.
X Start your vehicle with the key in the ignition lock. Doors
Important safety notes
G
WARNING
Only for the United Kingdom: if the vehicle
has been locked with the key or with KEY-
LESS-GO, the double lock function is activa-
ted as standard. It is then not possible to open
the doors from inside the vehicle.
Therefore, do not leave any people behind in
the vehicle, particularly children, elderly peo-
ple or people requiring special assistance. As
ar esult, they may not be able to free them-
selves in the event of an emergency. They
could be seriously or even fatally injured by
prolonged exposure to extremely high or low
temperatures, for example. In this case, res-
cuing people from outside the vehicle is diffi-
cult.
Deactivate the interior motion sensor before
you lock the vehicle. The doors can then be
opened from the inside after the vehicle has
been locked from the outside. G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open adoor from inside the vehicle at any
time, even if it has been locked
R start the vehicle using akey which has been
left in the vehicle
R release the parking brake
They could thereby endanger themselves and
others. Never leave children unsupervised in
the vehicle. Always take the key with you
when leaving the vehicle, even if you are only
leaving it for ashort time. Unlocking and opening the doors
from the inside
For all countries except the United King-
dom: you can open adoor from inside the
vehicle even if it has been locked. If the vehi-
cle has previously been locked with the key
or with KEYLESS-GO, opening adoor from the
inside will trigger the anti-theft alarm system.
Switch off the alarm (Y page 71).82
DoorsOpening and closing

!
Never open the bonnet if awindscreen
wiper arm has been folded awayf rom the
windscreen.
Never fold awindscreen wiper arm without
aw iper bladeb ack onto the windscreen.
Hold the windscreen wiper arm firmly when
you change the wiper blade. If you release
the windscreen wiper arm without awiper
bladea nd it falls onto the windscreen, the
windscreen may be damagedbyt he force
of the impact.
Mercedes-Benz recommends that you have
the wiper blades changed at aqualified
specialist workshop.
! To avoi ddamaging th ewindscree nwiper
blades, mak esure that you touc honly the
wiper arm of the windscreen wiper.
Replacing th ewiper blades Removing th
ewiper blades
X Remove the key fro mthe ignition lock or
tur nthe key to position 0(KEYLESS-GO).
X Fold the wiper arm away from the wind-
screen until it engages. X
Firmly press release knob :and pull the
wiper blade upwards from the wiper arm in
the direction of the arrow. Fitting the wiper blades
X
Position the new wiper blade in the retainer
on the wiper arm and slide it into place in
the opposite direction to the arrow.
The wiper blade audibly engages.
X Make sure that wiper blade is seated cor-
rectly.
X Fold the wiper arm back onto the wind-
screen. Problems with the windscreen wipers
The windscreen wipers are obstructed X
For safety reasons, you should remove the
key from the ignition lock.
or
X Switch off the engine using the Start/Stop
button and open the driver's door.
X Remove the cause of the obstruction.
X Switch the windscreen wipers back on.
The windscreen wipers are inoperative The windscreen wiper drive is malfunctioning.
X
Select another wiper speed on the combi-
nation switch.
X Have the windscreen wipers checked at a
qualified specialist workshop. 122
Windscreen wipersLights and windscreen wipers

Problem Possible causes/consequences and
M Solutions
Vehicles with
apetrol
engine:
The engine is not run-
ning smoothly and is
misfiring. There is
amalfunction in the engine electronics or in amechanical
componentoft he 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 aqualified specialist
workshop. The coolant tempera-
ture display is showing
more than 120 †. The
coolant warning lamp
may also be lit 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 299). 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. Automatic transmission
Important safety notes
G
WARNING
If the engine speed is above the idling speed
and you engage transmission position Dor
R,t he vehicle could pull away suddenly. There
is ar isk of an accident.
When engaging transmission position Dor R,
always firmly depress the brake pedal and do
not simultaneously accelerate. Selector lever
Overview of transmission positions Selector lever in AMG vehicles with
Pbutton
j Park position with parking lock
k Reverse gear
i Neutral
h Drive 148
Automatic transmissionDriving and parking

tha
tstore dast he limi tspeed. You could oth-
erwise cause an accident.
You can only exceed the limit speed stored if
you deactivate variable SPEEDTRONIC:
R using the cruise control lever
R by depressin gthe accelerator pedal
beyond the pressure point (kickdown)
It is not possible to deactivate variable
SPEEDTRONIC by braking. X
Check whether LIM indicator lamp :is on.
If it is on, variable SPEEDTRONIC is already
selected.
If it is not ,press the cruise contro llever in
the direction of arrow ;.
LIM indicator lamp :in the cruise control
lever lights up. Variable SPEEDTRONIC is
selected.
Storing the current speed X
Briefly press the cruise contro llever
up : or down ;.
The curren tspeed is stored and shown in
the multifunction display. The segments in the multifunction display
light up from the start of the scale up to the
stored speed.
You can use the cruise contro llever to limit
the speed to any speed above 30 km/ hwhile
the engine is running.
Storing the current speed and calling up
the last stored speed G
WARNING
Only select astored speed if you know what
that speed is and whether it is suitable for the
current driving and traffic situation. Other-
wise, sudden braking could endanger you or
others. X
Briefly pull the cruise control lever towards
you :.
Setting aspeed X
To adjust the se tspeed in 10 km/h
increments: brieflypress the cruise con-
trol lever up :past the pressure point for Drivin
gsystems
169Driving and parking Z

X
Press the abutton.
The multifunction display shows Speed
Limit Assist.
X Press the :button.
The curren tselection is displayed.
X To activate or deactivate: pressa.
If the Speed Limit Assist message function
is activated, adetected speed limit is auto-
matically displayed for five seconds. Other
items in the multifunction display are not
shown during this time.
If Speed Limit Assist is operational and the
message function is activated, the multifunc-
tion display shows the Äsymbol when the
ignition is switched on.
Showing the distance display X
Press the =or; button on the steer-
ing wheel to select the Assist. menu.
X Press the 9or: button to select
Distanc edisplay .
X Press the abutton.
The DISTRONIC PLUS distanc edisplay
appears in the multifunction display
(Y page 176).
If the Sensors deactivated message
appears, the radar sensor system is deacti-
vated.
X Check whether or not the radar sensor sys-
tem is permitted to be activated
(Y page 368).
X Switc hont he radar sensor system
(Y page 225).
Deactivating/activating ESP ®G
WARNING
If you deactivat eESP®
,E SP ®
no longer sta-
bilises the vehicle. There is an increased risk
of skidding and an accident.
Only deactivat eESP®
in the situation sdescri-
bed in the following. Activating/deactivating ESP
®
on AMG vehi-
cles (Y page 66).
For further information about ESP ®
,s ee
(Y page 65).
X Start the engine.
X Press the =or; button on the steer-
ing wheel to select the Assist. menu.
X Press the 9or: button to select
ESP .
X Press the abutton.
The curren tselection is displayed.
X To activate/deactivate: press thea
button again.
ESP ®
is deactivated if the åwarning lamp
in the instrument cluster lights up continu-
ously when the engin eisrunning.
If the ÷ warning lamp and the åwarn-
ing lamp are lit continuously, ESP ®
is not
available due to amalfunction.
It may be best to deactivat eESP®
in the fol-
lowing situations:
R when using snow chains
R in deep snow
R on sand or gravel
Observe the information on warning lamps
(Y page 263).
Observe the information on display messages
(Y page 232).
Activating/deactivating PRE-SAFE ®
Brake PRE-SAFE
®
Brak eiso nly available in vehicles
with DISTRONIC PLUS.
X Press the =or; button on the steer-
ing wheel to select the Assist. menu.
X Press the 9or: button to select
PRE-SAF EBrake .
X Press the abutton.
The curren tselection is displayed.
X To activate/deactivate: press thea
button again. Menus and submenus
219On-boardcomputer and displays Z

Problem Possible causes/consequences and
M Solutions
J
The red brake system
warning lamp comes on
while the vehicle is
moving.
Awarning tone
also sounds. You are driving with the parking brake applied.
X
Release the parking brake.
The warning lamp goes out and the warning tone ceases. 6
The red SRS warning
lamp is lit while the
engine is running.
There is
amalfunction in the SRS (Supplemental Restraint Sys-
tem).
G WARNING
The airbags or belt tensioners may either be triggered uninten-
tionally or, in the event of an accident, may not be triggered.
This poses an increased risk of injury.
X Drive on carefully.
X Have SRS checked at aqualified specialist workshop immedi-
ately.
For further information about the Supplemental Restraint System,
see (Y page 41). Engine
Problem Possible causes/consequences and
M Solutions
;
The yellowe
ngine diag-
nosticsw arning lamp
lights up while the
engine is running. There may be
afault, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system (for vehicles with petrol engines)
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 aqualified
specialist workshop. Vehicles with
adiesel engine: the fuel tank has been run dry
(Y page 158).
X Start the engine three to four times after refuelling.
If the yellow engine diagnostics warning lamp goes out, emer-
gency running mode is cancelled. The vehicle need not be
checked. 266
Warning and indicator lampsint
he instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
X
Leave the vehicle and keep asafe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and top up the coolant, observing the
warning notes (Y page 299).
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
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. Driving systems
Problem Possible causes/consequences and
M Solutions
·
The red distance warn-
ing lamp lights up while
the vehicle is in motion.
The distance to the vehicle in front is too small for the speed
selected.
X
Increase the distance. ·
The red distance warn-
ing lamp lights up while
the vehicle is in motion.
Aw
arning tone also
sounds. You are approaching
avehicle or astationar yobstacle in your line
of travel at to ohigh aspeed.
X Be prepared to brak eimmediately.
X Pay careful attentio ntothetraffic situation. You may have to
brak eort akee vasive action.
Further informatio nonDISTRONICPLUS(Ypage 170).
Further informatio nonPRE-SAFE ®
Brake (Y page 68). Warning and indicator lamps in th
einstrumen tcluster
269On-boar dcomputer and displays Z

X
Make sure that the windscreen wipers are
switched off.
X Pull release lever :on the bonnet.
The bonnet is released. X
Reach into the gap, pull bonnet catch han-
dle ;up and lift the bonnet.
If you lift the bonnet by approximately
40 cm, the bonnet is opened and held open
automatically by the gas-filled strut.
Closing the bonnet G
WARNING
Make sure that nobody can become trapped
as you close the bonnet.
X Lower the bonnet and let it fall from a
height of approximately 20 cm.
X Check that the bonnet has engaged prop-
erly.
If the bonnet can be raised slightly, it is not
properly engaged. Open it again and close
it with alittle more force. Radiator
Vehicles with adiesel engine: do not cover
the radiator .Donot use thermal mats, insect
protection covers or anything similar. Doing
so can cause the Onboard Diagnostics Sys-
tem to display inaccurate values. Some of
these values are legally required and must
always be correct. Engine oil
General notes Dependin
gonyour driving style, the vehicle
consumes up to 0.8 lofoil per 1,000 km. The
oil consumption may be higher than this when
the vehicle is new or if you frequently drive at
high engine speeds.
Dependin gonthe engine, the oil dipstick may
be installed at adifferent location.
When checking the oil level:
R park the vehicle on alevel surface.
R the engine should be switched off for
approximately five minutes if the engine is
at normal operating temperature.
R if the engine is not at normal operating
temperature, e.g. if the engine was only
started briefly: wait about 30 minutes
before carrying out the measurement. Engine compartment
297Maintenance and care Z