MERCEDES-BENZ A CLASS 2012 Owners Manual
Manufacturer: MERCEDES-BENZ, Model Year: 2012, Model line: A CLASS, Model: MERCEDES-BENZ A CLASS 2012Pages: 356, PDF Size: 4.96 MB
Page 251 of 356

Display messages Possible causes/consequences and
M SolutionsPark Assist inoper‐
ative You have just carried out a large number of turning or parking
manoeuvres.
Active Parking Assist will become available again after approx-
imately ten minutes (
Y page 186).
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Switch off and restart the engine.
If the display message continues to be displayed:
X Visit a qualified specialist workshop. PARKTRONIC is faulty.
X
Visit a qualified specialist workshop. DISTRONIC PLUS off DISTRONIC PLUS has been deactivated (
Y page 173). If it was
deactivated automatically, a warning tone also sounds. DISTRONIC PLUS
available again DISTRONIC PLUS is operational again after having been tempo-
rarily unavailable. You can now reactivate DISTRONIC PLUS
(Y page 173).
DISTRONIC PLUS cur‐
rently
unavailable
See Owner's Manual DISTRONIC PLUS is temporarily inoperative. Possible causes:
R
the function is impaired due to heavy rain or snow.
R the sensors in the radiator trim are dirty
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
A warning tone also sounds.
Once
the causes listed above no longer apply, the display message
goes out.
DISTRONIC 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 Secure the vehicle against rolling away ( Y page 162).
X Clean the sensors in the radiator trim (Y page 294).
X Restart the engine. Display messages
249
On-board computer and displays Z
Page 252 of 356

Display messages Possible causes/consequences and
M SolutionsDISTRONIC PLUS
inoperative DISTRONIC PLUS is faulty. Adaptive Brake Assist may also have
failed.
A warning tone also sounds.
X
Visit a qualified specialist workshop. DISTRONIC PLUS
inactive You have depressed the accelerator pedal. DISTRONIC PLUS is no
longer controlling the speed of the vehicle.
X
Remove your foot from the accelerator pedal. DISTRONIC PLUS
--- km/h An activation condition for DISTRONIC PLUS is not fulfilled.
X
Check the activation conditions for DISTRONIC PLUS
(Y page 175). DISTRONIC PLUS and
SPEEDTRONIC inop‐
erative DISTRONIC PLUS and SPEEDTRONIC are faulty. A warning tone
also sounds.
X
Visit a qualified specialist workshop. Cruise control and
SPEEDTRONIC inop‐
erative SPEEDTRONIC and cruise control are malfunctioning.
A warning tone also sounds.
X
Visit a qualified specialist workshop. Limit
--- km/h While depressing the accelerator pedal beyond the pressure point
(kickdown), SPEEDTRONIC cannot be activated.
Cruise control
--- km/h A condition for activating cruise control has not been met.
You have tried to store a speed below
30 km/h, for example.
X If conditions permit, drive faster than 30 km/h and store the
speed.
X Check the activation conditions for cruise control
(Y page 169). 120 km/h
Maximum speed
exceeded Only for certain countries: the maximum speed has been excee-
ded.
In addition, the multifunction display shows
120 km/h.
X Drive more slowly.250
Display messages
On-board computer and displays
Page 253 of 356

Tyres
Display messages Possible causes/consequences and
M SolutionsTyre pressure
Check tyres The tyre pressure loss warning system has detected a significant
loss in pressure.
A warning tone also sounds.
G WARNING
With tyre pressures which are too low, there is a risk of the 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 162).
X Check the tyres and, if necessary, follow the instructions for a
flat tyre (Y page 300).
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 323). Check tyre pres‐
sures
then restart Run
Flat Indicator The tyre pressure loss warning system generated a display mes-
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 323). Run Flat Indicator
inoperative The tyre pressure loss warning system is faulty.
X
Visit a qualified specialist workshop. Display messages
251
On-board computer and displays Z
Page 254 of 356

Vehicle
Display messages Possible causes/consequences and
M SolutionsTo start engine,
shift to either P
or N You have attempted to start the engine with the transmission in
position R or D.
X
Shift the transmission to position P or N.Auxiliary battery
malfunction The auxiliary battery for the automatic transmission is no longer
being charged.
X
Visit a qualified specialist workshop at the next opportunity.
X Until then, set the automatic transmission to position P before
you switch off the engine.
X Before leaving the vehicle, apply the electric parking brake. Depress brake to
start engine You have attempted to start the engine with the transmission in
position N without depressing the brake pedal.
X
Depress the brake pedal. To shift out of P
or N
depress brake and
start engine You have attempted to shift the transmission to position
R or D
without starting the engine.
X Start the engine.
X Depress the brake pedal.
i It is only possible to shift the transmission from position P to
the desired position if you depress the brake pedal. Only then
can the parking lock be deactivated. If you do not depress the
brake pedal, the DIRECT SELECT lever can still be moved but
the parking lock remains engaged.
i At
transmission fluid temperatures below Ò20 † you can only
shift out of position P into another transmission position when
the engine is running. Apply brake to
deselect Park (P)
position You have attempted to move the transmission selector lever to
position R, N or D without depressing the brake pedal.
X
Depress the brake pedal. Risk of vehicle
rolling
Transmission not
in P The driver's door is open and the transmission is in position
R, N
or D.
A warning tone also sounds.
X Shift the transmission to position P.
X Secure the vehicle against rolling away ( Y page 162).252
Display messages
On-board computer and displays
Page 255 of 356

Display messages Possible causes/consequences and
M SolutionsWithout changing
gear,
consult workshop You cannot change the transmission position due to a malfunction.
A warning tone also sounds.
If transmission position
D is selected:
X Drive to a qualified specialist workshop without shifting the
transmission from position D.
If transmission position R, N or P is selected:
X Consult a qualified specialist workshop. Only select Park
(P) when
vehicle
is station‐
ary The vehicle is moving.
X
Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Shift the transmission to position P.Reversing not
poss.
Consult work‐
shop The automatic transmission is malfunctioning. You cannot drive in
reverse.
X
Visit a qualified specialist workshop. Transmission Mal‐
function The automatic transmission is malfunctioning.
X
Visit a qualified specialist workshop. Transmission mal‐
function Stop The automatic transmission is malfunctioning.
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 162).
X Consult a qualified specialist workshop. Stop vehicle Shift
to P Leave engine
running The automatic transmission has overheated.
X
Drive on carefully.
If the display message disappears, the automatic transmission
is available again.
If the display message continues to be displayed:
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 162).
X Wait until the automatic transmission has cooled off and the
display message goes out. Display messages
253On-board computer and displays Z
Page 256 of 356

Display messages Possible causes/consequences and
M SolutionsTrans. oil overhea‐
ted Drive on with
care AMG vehicles: the transmission oil has overheated.
Manual drive program
M and the temporarily active manual drive
program are no longer available. The engine power output is
reduced.
X Allow the vehicle to cool down. 4matic currently
unavailable 4MATIC (permanent all-wheel drive) has overheated. The vehicle
is only driven by the front wheels.
X
Drive on.
The airflow cools 4MATIC more quickly.
When
the display message goes out, 4MATIC is available again
and the vehicle is driven by all four wheels. 4matic inoperative 4MATIC is malfunctioning. The vehicle is only driven by the front
wheels.
X
Visit a qualified specialist workshop. A The tailgate is open.
G WARNING
When the engine is running, exhaust gases can enter the vehicle
interior if the tailgate is open.
There is a risk of poisoning.
X Close the tailgate. ? The bonnet is open.
A warning tone also sounds.
G WARNING
The open bonnet may then block your view when the vehicle is in
motion.
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.
X Apply the electric parking brake.
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 or because it has already been triggered.
X
Visit a qualified specialist workshop. C At least one door is open. A warning tone also sounds.
X
Close all doors.254
Display messages
On-board computer and displays
Page 257 of 356

Display messages Possible causes/consequences and
M Solutionsj
Check trailer
hitch lock The trailer tow hitch is not correctly engaged.
A warning tone also sounds.
X
Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Apply the electric parking brake.
X Engage the trailer coupling's ball coupling in the end position
(Y page 203).
Otherwise, the trailer may detach itself. Ð
Power
steering mal‐
function See Own‐
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. &
inoperative Bat‐
tery low You have attempted to switch on the auxiliary heating or to acti-
vate
a departure time using the on-board computer after operating
the auxiliary heating twice.
X Let the engine run for 10 seconds.
The auxiliary heating is operational again. The on-board voltage is too low. The auxiliary heating has switched
itself off or cannot be switched on
(Y page 134).
X Drive for a longer distance.
The
battery is being charged. The auxiliary heating is operational
again as soon as the on-board electrical system voltage is suf-
ficient. &
inoperative
Refuel
vehicle There is too little fuel in the fuel tank. The auxiliary heating cannot
be switched on (
Y page 134).
X Refuel at the nearest filling station. Display messages
255
On-board computer and displays Z
Page 258 of 356

Display messages Possible causes/consequences and
M Solutions&
inoperative See
Owner's Man. The auxiliary heating has a temporary malfunction or is 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 heat-
ing, waiting several minutes between each attempt
(Y page 134).
X If the auxiliary heating does not switch on, consult a qualified
specialist workshop. Telephone No
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. ¥
Top
up washer fluid The washer fluid level in the washer fluid reservoir has dropped
below the minimum.
i
If, during the winter months, you do not add antifreeze to the
washer
fluid, it may freeze in the washer fluid container. In this
case, the Top up washer fluid display message may appear
in the multifunction display.
X Top up the washer fluid ( Y page 289).Wiper malfunction‐
ing The windscreen wipers are defective.
X
Visit a qualified specialist workshop. Hazard warning
lamps malfunction‐
ing The hazard warning lamps are faulty.
X
Visit a qualified specialist workshop. Key
Display messages Possible causes/consequences and
M Solutions+
Key does not
belong to vehicle You have put the wrong key in the ignition lock.
X
Use the correct key. +
Replace key The key needs to be replaced.
X
Visit a qualified specialist workshop.256
Display messages
On-board computer and displays
Page 259 of 356

Warning and indicator lamps in the instrument cluster
Seat belts
Problem Possible causes/consequences and
M Solutionsü
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 46).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 46).
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 46).
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
intermittent audible
warning sounds. The driver or front passenger has not fastened their seat belt. At
the
same time, you are driving faster than 25 km/h or have briefly
driven faster than 25 km/h.
X Fasten your seat belt ( Y page 46).
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. Warning and indicator lamps in the instrument cluster
257
On-board computer and displays Z
Page 260 of 356

Safety systems
Problem Possible causes/consequences and
M SolutionsJ
The red brake system
warning
lamp is lit while
the engine is running. 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 162).
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.
BAS
(Brake Assist), COLLISION PREVENTION ASSIST, ESP ®
(Elec-
tronic Stability Program), PRE-SAFE ®
, the HOLD function, hill start
assist, the adaptive brake lights and ESP ®
trailer stabilisation are
also therefore 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 may 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 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 be unavailable. 258
Warning and indicator lamps in the instrument cluster
On-board computer and displays