check engine MERCEDES-BENZ E-CLASS COUPE 2015 Owner's Guide

Display messages
Possible causes/consequences and
M
MSolutions j
Check Check
trailer
trailer hitch
hitch
lock
lock The trailer tow hitch is not correctly engaged.
A warning tone also sounds.
G WARNING
If the ball coupling is not engaged, the trailer may come loose. There
is a risk of an accident.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Apply the parking brake.
X Engage the trailer coupling's ball coupling in the end position
(Y page 203). &
inoperative inoperative
Battery
Battery
Low
Low The on-board voltage is too low. The auxiliary heating has switched
itself off or cannot be switched on (Y page 124).
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 Refuel inoperative Refuel
vehicle vehicle There is too little fuel in the fuel tank. The auxiliary heating cannot be
switched on (Y page 124).
X Refuel at the nearest filling station. &
inoperative inoperative
See
SeeOwn‐
Own‐
er's Man.
er'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 heating,
waiting several minutes between each attempt (Y page 124).
X If the auxiliary heating does not switch on, consult a qualified spe-
cialist workshop. Telephone Telephone
No
Noservice
service Your vehicle is outside the network provider's transmitter/receiver
range.
X Wait until the mobile phone operational readiness symbol appears
in the multifunction display. 244
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Ð
Power steering mal‐ Power steering mal‐
function See Own‐ function See Own‐
er's Manual er's Manual The power steering assistance is faulty.
A warning tone also sounds.
G WARNING
You will need to use more force to steer.
There is a risk of an accident.
X Check whether you are able to apply the extra force required.
X If you are able to steer safely: carefully drive on to a qualified
specialist workshop.
X If you are unable to steer safely: do not drive on. Contact the
nearest qualified specialist workshop. ¥
Top up washer fluid Top up washer fluid The washer fluid level in the washer fluid reservoir has dropped below
the minimum.
X Top up the washer fluid (Y page 287).Key
Display messages
Possible causes/consequences and
M
MSolutions Â
Key Key
does
does not
notbelong
belong
to vehicle
to vehicle You have put the wrong key in the ignition lock.
X Use the correct key. Â
Replace key Replace key The key needs to be replaced.
X Consult a qualified specialist workshop. Â
Change Change
key
keybatteries
batteries The battery of the KEYLESS-GO key is discharged.
X Change the replace (Y page 77).Â
Key not detected Key not detected
(red display message) The KEYLESS-GO key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle cen-
trally or start the engine.
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 150).
X Locate the KEYLESS-GO key. Display
messages
245On-board computer and displays Z

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
M Solutions ÷
N
The yellow ESP ®
warning lamp flashes while the vehicle is in motion.
ESP ®
or traction control has intervened because there is a risk of skidding or at
least one wheel has started to spin.
Cruise control or DISTRONIC PLUS is deactivated.
X Only depress the accelerator pedal as far as necessary when pulling away.
X Accelerate more gently while the vehicle is in motion.
X Adapt your driving style to suit the road and weather conditions.
X Do not deactivate ESP ®
.
In rare cases (Y page 68) it may be better to deactivate ESP ®
.
Observe the important safety notes on ESP ®
(Y page 67). å
N
The yellow ESP ®
OFF warning lamp is lit while the engine is running.
ESP ®
is deactivated.
G WARNING
If ESP ®
is deactivated, ESP ®
is unable to stabilise the vehicle.
Further driving systems or driving safety systems are thus restricted, e.g. Active
Blind Spot Assist. The system does not perform course-correcting braking appli-
cations.
There is an increased danger of skidding and risk of an accident.
X Reactivate ESP ®
.
In rare cases (Y page 68) it may be better to deactivate ESP ®
.
Observe the important safety notes on ESP ®
(Y page 67).
X Adapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
X Drive on carefully.
X Contact a qualified specialist workshop immediately and have the ESP ®
system
checked. 250
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ֌
N
The yellow ESP ®
and ESP ®
OFF warning lamps are lit while the engine is running.
ESP ®
is faulty.
Other driving and driving safety systems may also be faulty.
G WARNING
The brake system continues to function normally, but without the functions listed above.
The braking distance may thus increase in an emergency braking situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased danger of skidding and risk of an accident.
X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Consult a qualified specialist workshop immediately. 6
N
The red restraint system warning lamp is lit while the engine is running.
The restraint system is faulty.
G WARNING
The airbags or belt tensioners may either be triggered unintentionally or, in the
event of an accident, may not be triggered.
This poses an increased risk of injury. X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Have the restraint system checked immediately at a qualified specialist work-
shop.
Observe the additional information on the restraint system (Y page 36).Warning and indicator lamps in the instrument cluster
251On-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 run-
ning.
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 (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 Consult a qualified specialist workshop immediately.
Vehicles with a diesel engine: the fuel tank has been run dry (Y page 150).
X After refuelling start the engine three to four times.
If the yellow engine diagnostics warning lamp goes out, emergency running
mode is cancelled. You do not need to have the vehicle checked. 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 scale.
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 conditions,
and switch off the engine. Do not continue driving under any circumstances.
X Safeguard the vehicle against rolling away (Y page 150).
X Consult a qualified specialist workshop. 252
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ?
N
The red coolant warning lamp comes on while the engine is running.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator may be blocked or the electric engine radiator fan may be malfunctioning.
The coolant is too hot and the engine is no longer being cooled sufficiently.
X Observe the additional display messages in the multifunction display.
X Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 150).
X Leave the vehicle and keep a safe 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 286).
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 Do not start the engine again until the coolant temperature is below 120 †. The
engine may otherwise be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid putting the engine under heavy load as you do so, e.g. driving in moun-
tainous terrain and stop-start traffic. ?
N
The red coolant warning lamp comes on while the engine is running. A warning
tone also sounds.
The coolant temperature has exceeded 120 †. The airflow to the engine radiator
may be blocked or the coolant level may be too low.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Never drive with an overheated engine. Driving when your engine is overheated
can cause some fluids which may have leaked into the engine compartment to
catch fire.
In addition, steam from an overheated engine can cause serious burns, which can
occur just by opening the bonnet.
There is a risk of injury.
X Observe the additional display messages in the multifunction display.
X Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 150).
X Leave the vehicle and keep a safe 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 286).
X If you have to top up the coolant frequently, have the engine cooling system
checked. Warning and indicator lamps in the instrument cluster
253On-board computer and displays Z

Even if the active bonnet has been triggered, you
can still continue driving and have it reset at a
qualified specialist workshop. If you pull the
bonnet release lever, you must reset the bonnet
before driving on.
Resetting G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. X
Open the bonnet (Y page 284).
X With both hands, lift the bonnet up in the
centre A. The bonnet is open wide enough
when both lids of bonnet lifter ;no longer
move.
If you push the lids back, you will notice resist-
ance.
X Release bonnet :.
X Check whether the lids of bonnet lifter ;are
resting on housings =(arrow).
X The lids of bonnet lifter ;
; are resting on
the housings: close bonnet:
(Y page 285).
or X The lids of bonnet lifter ; ;are not resting
on the housings: first, lift up bonnet :on
left-hand side ?and then on right-hand side B. Lift up bonnet
:until the respective lid of
bonnet lifter ;no longer moves.
The lids of bonnet lifter ;must rest on hous-
ings =(arrow).
X Close bonnet :(Ypage 285).
If you cannot close bonnet :or if the L
symbol appears in the multifunction display,
repeat the steps.
If the bonnet still does not engage correctly or
the L symbol appears in the multifunction
display, do not drive any further. Contact a quali- fied specialist workshop.
If active bonnet :has been triggered, it will be
raised at the back by about 50 mm. Lids ;will
then no longer rest on housings =. The active
bonnet is triggered by pyrotechnics.
Opening the bonnet G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. G
WARNING
When the bonnet is open, and the windscreen wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windscreen wipers and
the ignition before opening the bonnet.
! Make sure that the windscreen wipers are
not folded away from the windscreen. Other-
wise, you could damage the windscreen wip-
ers or the bonnet. 284
Engine compartmentMaintenance and care

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 automat-
ically by the gas-filled strut.
Closing the bonnet X
Lower the bonnet and let it fall from a height
of approximately 20 cm.
X Check that the bonnet has engaged properly.
If the bonnet can be raised slightly, it is not
properly engaged. Open it again and close it
with a little more force. Radiator
Vehicles with a diesel engine: do not cover
the radiator. Do not use thermal mats, insect
protection covers or anything similar. Doing so
can cause the Onboard Diagnostics System to
display inaccurate values. Some of these values are legally required and must always be correct. Engine oil
General notes Depending on your driving style, the vehicle
consumes up to 0.8 litres of oil per 1000 km. The
oil consumption may be higher than this when
the vehicle is new or if you frequently drive at
high engine speeds.
Depending on the engine, the oil dipstick may be installed at a different location.
When checking the oil level:
R park the vehicle on a level surface
R the engine should be switched off for approx-
imately five minutes if the engine is at normal
operating temperature
R if the engine is not at normal operating tem-
perature, e.g. if the engine was only started
briefly, wait approximately 30 minutes before carrying out the measurement
Checking the oil level using the oil dip-
stick G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. Example: vehicles with a petrol engine
X Pull oil dipstick :out of the oil dipstick tube.
X Wipe off oil dipstick :. Engine compartment
285Maintenance and care Z

X
Slowly slide oil dipstick :into the guide tube
to the stop, and take it out again.
If the level is between MIN mark =and MAX
mark ;, the oil level is correct.
X If the oil level has dropped to MIN mark =or
below, top up with 1.0 lof engine oil.
Topping up engine oil G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. G
WARNING
If engine oil comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Make sure that engine oil does not spill out
over the filler neck. Allow the engine to cool
down and thoroughly clean the components
that have come into contact with engine oil
before you start the engine. H
Environmental note
When topping up the oil, take care not to spill
any. If oil enters the soil or waterways, it is
harmful to the environment.
! Only use engine oils and oil filters that have
been approved for vehicles with a service sys-
tem. You can obtain a list of the engine oils
and oil filters tested and approved in accord-
ance with the Mercedes-Benz Specifications
for Service Products at any Mercedes-Benz
Service Centre. Damage to the engine or exhaust system is
caused by the following:
R using engine oils and oil filters that have not
been specifically approved for the service
system
R changing the engine oil and oil filter after
missing the change interval required by the
service system
R using engine oil additives
! Do not add too much oil. Topping up with too
much engine oil can result in damage to the
engine or to the catalytic converter. Have
excess engine oil siphoned off. Example
X Turn cap :anti-clockwise and remove it.
X Top up the engine oil.
If the oil level is at or below the MIN mark on
the oil dipstick, top up with 1.0 lof engine oil.
X Replace cap :on the filler neck and turn
clockwise.
Make sure that the cap locks securely into
place.
X Check the oil level again with the oil dipstick
(Y page 285).
For further information on engine oil, see
(Y page 332). Other service products
Checking the coolant level G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment. 286
Engine compartmentMaintenance and care

As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. G
WARNING
The cooling system is pressurised, particu-
larly when the engine is warm. If you open the cap, you could be scalded if hot coolant
sprays out. There is a risk of injury.
Let the engine cool down before you open the
cap. Wear gloves and eye protection. Open
the cap slowly to release the pressure. X
Park the vehicle on a level surface.
Only check the coolant level if the vehicle is
on a level surface and the engine has cooled
down.
X Turn the key to position 2in the ignition lock
(Y page 132).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (Y page 132).
X Check the coolant temperature display in the
instrument cluster.
The coolant temperature must be below
70 †.
X Turn the key to position 0in the ignition lock
(Y page 132).
X Slowly turn cap :half a turn anti-clockwise
to allow excess pressure to escape.
X Turn cap :further anti-clockwise and
remove it.
If the coolant is at the level of marker bar =
in the filler neck when cold, there is enough
coolant in coolant expansion tank ;.
If the coolant level is approximately 1.5 cm
above marker bar =in the filler neck when
warm, there is enough coolant in coolant
expansion tank ;. X
If necessary, top up with coolant that has
been tested and approved by Mercedes-Benz.
X Replace cap :and turn it clockwise as far as
it will go.
Further information on coolant (Y page 334).
Topping up the windscreen washer sys- tem G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. G
WARNING
If windscreen washer concentrate comes into contact with hot components of the engine or
the exhaust system, it can ignite. There is a
risk of fire and injury.
Make sure the windscreen washer concen-
trate does not come into contact with the filler neck. X
To open: pull cap:upwards by the tab.
X Top up with the premixed washer fluid.
X To close: press cap :onto the filler neck
until it engages.
If the washer fluid level drops below the recom- mended minimum of 1 litre, a message appears in the multifunction display prompting you to
top up the washer fluid (Y page 245). Engine compartment
287Maintenance and care Z