2015 MERCEDES-BENZ E-CLASS COUPE check engine light

Display messages
Possible causes/consequences and
M
MSolutions J
Release parking Release parking
brake brake You are driving with the parking brake applied. A warning tone also
sounds.
X Release the parking brake. J
Check brake fluid Check brake fluid
level level There is insufficient brake fluid in the brake fluid reservoir.
In addition, the red Jwarning lamp lights up in the instrument
cluster and a warning tone sounds.
G WARNING
Braking efficiency may be impaired.
There is a risk of an accident.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
X Safeguard the vehicle against rolling away (Y page 150).
X Consult a qualified specialist workshop.
X Do not top up the brake fluid. This does not correct the fault. #
Check Check
brake
brakepad
padwear
wear The brake pads/linings have reached their wear limit.
X Consult a qualified specialist workshop. G
Inoperative
Inoperative One or more main features of the Mercedes-Benz Contact system are
malfunctioning.
X Consult a qualified specialist workshop. Collision Preven‐
Collision Preven‐
tion Assist Plus tion Assist Plus
currently unavaila‐ currently unavaila‐
ble ble
See
SeeOwner's
Owner's Man‐
Man‐
ual
ual COLLISION PREVENTION ASSIST PLUS is temporarily inoperative.
Possible causes:
R the radar sensor system is temporarily inoperative, e.g. due to elec-
tromagnetic radiation emitted by nearby TV or radio stations or
other sources of electromagnetic radiation
R the system is outside the operating temperature range
R the on-board voltage is too low
Once the causes listed above no longer apply, the display message
goes out.
COLLISION PREVENTION ASSIST PLUS is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Safeguard the vehicle against rolling away (Y page 150).
X Restart the engine. Collision Preven‐ Collision Preven‐
tion Assist Plus tion Assist Plus
inoperative inoperative COLLISION PREVENTION ASSIST PLUS is temporarily inoperative due
to a malfunction. Adaptive Brake Assist may also have failed.
X Consult a qualified specialist workshop. Display
messages
225On-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

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

occupants from suffering acid burns should the
battery be damaged in the event of an accident.
In order for the battery to achieve the maximum possible service life, it must always be suffi-
ciently charged.
Like other batteries, the vehicle battery may
discharge over time if you do not use the vehicle. In such cases, have the battery disconnected ata qualified specialist workshop. You can also
charge the battery with a charger recommended
by Mercedes-Benz. For more information,
please contact a qualified specialist workshop.
Have the battery charge checked more fre-
quently if you use the vehicle mainly for short
trips or if you leave it standing idle for a lengthy period. Consult a qualified specialist workshop
if you wish to leave your vehicle parked up for a
long period of time.
When you park the vehicle, remove the key if you do not require any electrical consumers. The
vehicle will then use very little energy, thus con- serving battery power.
If the power supply has been interrupted, e.g. if the battery was discharged, you will have to:
R set the clock. Information on setting the clock
can be found in the Digital Owner's Manual.
On vehicles with a multimedia system, the
time is set automatically.
R reset the function for folding the exterior mir-
rors in/out automatically, by folding the mir-
rors out once (Y page 103). 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, naked 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 breathe in any battery gases. Do not
lean over the battery. Keep the batteries out
of the reach of children. Immediately rinse off battery acid thoroughly with plenty of clean
water and seek medical attention at once. 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 maximum
charging voltage of 14.8 V.
! Only charge the battery using the jump-start
connection point.
The jump-starting connection point is in the
engine compartment (Y page 305).
X Open the bonnet.
X Connect the battery charger to the positive
terminal and earth point in the same order as
when connecting the donor battery in the
jump-starting procedure (Y page 305).
If the indicator/warning lamps do not light up at
low temperatures, it is very likely that the dis-
charged battery has frozen. In this case, you
may neither charge the battery nor jump-start
the vehicle. The service life of a battery that has been thawed may be reduced. The starting char-
acteristics may be impaired, especially at low
temperatures. Have the thawed battery
checked at a qualified specialist workshop.
Never charge a battery still installed in the vehi-
cle unless a battery charger unit approved by
Mercedes-Benz is being used. A battery charger unit specially adapted for Mercedes-Benz vehi-
cles and tested and approved by Mercedes-
Benz is available as an accessory. This device
permits charging of the battery in position. Con-
tact a Mercedes-Benz Service Centre for infor-
mation and availability. Read the battery charg- er's operating instructions before charging the
battery. 304
Battery (vehicle)Breakdown assistance

Jump-starting
For the jump-starting procedure, use only the jump-starting connection point, consisting of a pos- itive terminal and an earth 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 breathe in any battery gases. Do not lean over the battery. Keep the batteries out of the reach of children. Immediately rinse off battery acid
thoroughly with plenty of clean water and seek medical attention at once. G
WARNING
During charging and jump-starting, explosive gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, naked flames, creating sparks and smoking. Ensure there is sufficient
ventilation 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 jump leads.
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.
! Vehicles with a petrol engine:
avoid repeated and lengthy starting attempts. Otherwise, the
non-combusted fuel may damage the catalytic converter.
If the indicator/warning lamps do not light up at low temperatures, it is very likely that the dis-
charged battery has frozen. In this case you may neither jump-start the vehicle nor charge the
battery. The service life of a battery that has been thawed may be reduced. The starting charac-
teristics may be impaired, especially at low temperatures. Have the thawed battery checked at a
qualified specialist workshop. Jump-starting
305Breakdown assistance Z