2012 MERCEDES-BENZ E-CLASS COUPE ECU

Tyres
Display messages Possible causes/consequences and
M Solutions
Tyre pressure
Check tyres The tyre pressure loss warning system has detected a significant
loss in pressure.
Aw
arning tone also sounds.
G WARNING
With tyre pressures which are too low, there is a ris kofthe fol-
lowing hazards:
R the tyres may burst, especially as the load and vehicle speed
increase.
R the tyres may wear excessively and/or unevenly, which may
greatly impair tyre traction.
R the driving characteristics, as well as steering and braking, may
be greatly impaired.
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
manoeuvres. Pay attention to the traffic conditions as you do
so.
X Secure the vehicle against rolling away (Y page 177).
X If there is a flat tyre, inspect the tyres (Y page 324).
X Check the tyre pressures and, if necessary, correct the tyre
pressure.
X Restart the tyre pressure loss warning system when the tyre
pressure is correct (Y page 345).Check tyre pres‐
sures
then restart Run
Flat Indicator The tyre pressure loss warning system generated a displaym
es-
sage and has not been restarted since.
X Set the correct tyre pressure in all four tyres.
X Restart the tyre pressure loss warning system (Y page 345).Run Flat Indicator
inoperative The tyre pressure loss warning system is faulty.
X
Visit a qualified specialist workshop. Display messages
269On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
M? The bonne
tis open. Awarning tone also sounds.
CLS Shooting Brake: the bonnet is open. A warning tone also
sounds.
G WARNING
The open bonne tmay then bloc kyour view when the vehicle is in
motion.
There is a risk of accident.
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 177).
X Close the bonnet.
If the active bonnet (pedestrian protection) has been triggered:
X Reset the bonnet (Y page 306).
X Close the bonnet. Active bonnet mal‐
function See Own‐
er's Manual The active bonnet (pedestrian protection) is not active due to a
malfunction.
The active bonnet (pedestrian protection) is not active due to a
malfunction or because it has already been triggered.
X Visit a qualified specialist workshop. C At least one door is open.
Awarning tone also sounds.
X Close all doors. _
Rear left seat
backrest not
locked or
Rear right seat back‐
rest not locked The backres
tinthe rear is not engaged on the left-hand and/or
right-hand side. Awarning tone also sounds.
X Push the backres tback until it engages. _
Front left seat
backrest not
locked or
Front right seat back‐
rest not locked The driver's or front-passenger seat backres
tis not engaged. A
warning tone also sounds.
X Push the backrest back until it engages. Display messages
271On-board computer and displays Z

Key
Display messages Possible causes/consequences and
M Solutions
Â
Key does not
belong to vehicle You have put the wrong key in the ignition lock.
X
Use the correct key. Â
Replace key The key needs to be replaced.
X
Visit a qualified specialist workshop. Â
Change key batter‐
ies The batteries of the KEYLESS-GO key are discharged.
X
Change the batteries ( Ypage 79). Â
Key not detected
(red display message) The KEYLESS-GO key is not in the vehicle.
Aw
arning tone also sounds.
If the engine is switched off, you can no longer loc kthe vehicle
centrally 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 177).
X Locate the KEYLESS-GO key. The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
Aw
arning tone also sounds.
X Pull ove rand stop the vehicle safely as soo nas possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 177).
X Operate the vehicle with the key in the ignition lock if necessary. Â
Key not detected
(white display mes-
sage) The KEYLESS-GO key cannot be detected at present.
X
Change the location of the key with the KEYLESS-GO functions
in the vehicle.
If the KEYLESS-GO key is still not detected:
X Operate the vehicle with the key in the ignition lock if necessary. Â
Key still in vehi‐
cle The KEYLESS-GO key has been detected inside the vehicle during
locking.
X
Remove the KEYLESS-GO key from the vehicle. 274
Display messagesOn-board computer and displays

Safety
Seat belts Problem Possible causes/consequences and
M Solutions
ü
Only for certain coun-
tries: the red seat belt
warning lamp lights up
for six seconds after
the engine starts. The seat belt warning lamp reminds the driver and front passenger
to fasten their seat belts.
X
Fasten your seat belt (Y page 50).ü
Only for certain coun-
tries: the red seat belt
warning lamp lights up
after the engine starts.
In addition, a warning
tone sounds for up to
six seconds. The driver's seat belt is not fastened.
X
Fasten your seat belt (Y page 50).
The warning tone ceases. ü
The red seat belt warn-
ing lamp lights up after
the engine starts, as
soon as the driver's or
the front-passenger
door is closed. The driver or front passenger has not fastened their seat belt.
X
Fasten your seat belt (Y page 50).
The warning lamp goes out. There are objects on the front-passenger seat.
X
Remove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out. ü
The red seat belt warn-
ing lamp flashes and an
intermittenta udible
warning sounds. The driver or passenger has no
tfastened their seat belt .Atthe
same time, the car is being driven faster than 25 km/h or has been
briefly driven faster than 25 km/h.
X Fasten your seat belt (Y page 50).
The warning lamp goes out and the intermittent warning tone
ceases. There are objects on the front-passenger seat. At the same time,
you are driving faster than 25 km/h or have briefly driven faster
than 25 km/h.
X
Remove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out and the intermittent warning tone
ceases. 276
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Safety systems
Problem Possible causes/consequences and
M Solutions
J
The red brake system
warning lamp comes on
while the engine is run-
ning. A warning tone
also sounds. There is insufficient brake fluid in the brake fluid reservoir.
G WARNING
The 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 Secure the vehicle against rolling away (Y page 177).
X Do not top up the brake fluid. Topping up will not rectify the
fault.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. !
The yellow ABS warning
lamp is lit while the
engine is running. ABS (Anti-lock Brake System) has been deactivated due to a fault.
For this reason, BAS (Brake Assist), BAS PLUS, ESP ®
(Electronic
Stability Program), PRE-SAFE ®
,P RE-SAFE ®
Brake ,the HOLD func-
tion, hill start assist, the adaptive brake lights and ESP ®
trailer
stabilisation are also deactivated, for example.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop.
If the ABS control unit is faulty, there is also a possibility that other
systems, such as the navigation system or the automatic trans-
mission, will not be available. Warning and indicator lamps in the instrument cluster
277On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
8
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning.
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. ?
The red coolant warn-
ing lamp lights up while
the engine is running
and the coolant tem-
perature 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 traf-
fic conditions, and switch off the engine. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away (Y page 177).
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
281On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
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 mal-
functioning.
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 traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 177).
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 310).
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
under 120 †. The engine may otherwise be damaged.
X Drive 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. ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. 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.
Steam from an overheated engine can cause serious burns, which
can occur just by opening the bonnet.
This poses a risk of injury.
X Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 177).282
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Useful information
i This Owner's Manual describes all mod-
els, series and optional equipment for your
vehicle that were available at the time of
going to press. National variations are pos-
sible. Note that your vehicle may not be
equipped with all of the functions descri-
bed. This is also the case for systems and
functions relevant to safety.
i Read the information on qualified special-
ist workshops: (Y page 23). Stowage areas
Loading guidelines (Coupé)
G
WARNING
Secure and position the load as described in
the loading guidelines.
Otherwise, vehicle occupants could
be injured by the load being thrown around in
the even tofsharp braking, a sudden change
in direction or an accident.
You will find further information in the "Secur-
ing a load" section.
Even if you follow all the loading guidelines,
the load will increase the risk of injury in the
event of an accident. G
WARNING
Keep the boot lid closed while the vehicle is
in operation. Otherwise, you could be pois-
oned by exhaust fumes entering the vehicle.
The handling characteristics of a laden vehi-
cle are dependent on the distribution of the
load within the vehicle. For this reason, you
should observe the following notes when
transporting a load:
R when transporting a load, never exceed the
maximum permissible gross vehicle weight or the permissible axle loads for the vehicle
(including occupants).
R position heavy loads as far forwards as pos-
sible and as low down in the boot as pos-
sible.
R the load must not protrude above the upper
edge of the seat backrests.
R always place the load against the rear or
front seat backrests. Make sure that the
seat backrests are securely locked into
place.
R always place the load behind unoccupied
seats if possible.
R secure the load with sufficiently strong and
wear-resistant lashing material. pad sharp
edges for protection.
i Load restraints are available at any quali-
fied specialist workshop, e.g. a Mercedes-
Benz Service Centre. Stowage compartments
Important safety notes G
WARNING
The stowage compartments must be closed
when items are stored in them. Luggage nets
are not designed to secure heavy items of
luggage.
You or other vehicle occupants could be
injured by objects being thrown around if you:
R brake sharply
R change direction suddenly
R are involved in an accident
Sharp-edged and fragile objects must not be
placed in the luggage net.
Do not place hard objects in the map pockets.
Objects must not protrude from the map
pockets. 286
Stowage areasStowing and features