2012 MERCEDES-BENZ A CLASS sat nav

Safety systems
Display messages Possible causes/consequences and
M Solutions!÷
currently unavail‐
able See Owner's
Manual ABS (Anti-lock Braking System), ESP
®
(Electronic Stability Pro-
gram), BAS (Brake Assist), PRE-SAFE ®
, the HOLD function, hill
start assist and ESP ®
trailer stabilisation are temporarily unavail-
able.
The adaptive brake lights and COLLISION PREVENTION ASSIST
may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster.
ATTENTION ASSIST is deactivated.
Possible causes:
R self-diagnosis is not yet complete.
R the on-board voltage may be insufficient
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 Carefully drive on a suitable stretch of road, making slight steer-
ing movements, at a speed above

20 km/h.
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
X Drive on carefully.
X Visit a qualified specialist workshop. !÷
inoperative See
Owner's Manual ABS, ESP
®
, BAS, PRE-SAFE ®
, the HOLD function, hill start assist
and
ESP®
trailer stabilisation are unavailable due to a malfunction.
The adaptive brake lights and COLLISION PREVENTION ASSIST
may also have failed.
In addition, the J, ÷, å and ! warning lamps light
up in the instrument cluster.
ATTENTION ASSIST is deactivated.
G WARNING230
Display messages
On-board computer and displays

Display messages Possible causes/consequences and
M SolutionsThe 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 Drive on carefully.
X Visit a qualified specialist workshop immediately. ÷
currently unavail‐
able See Owner's
Manual ESP
®
, BAS, PRE-SAFE ®
, the HOLD function, hill start assist and
ESP ®
trailer stabilisation are temporarily unavailable.
The adaptive brake lights and COLLISION PREVENTION ASSIST
may also have failed.
In addition, the ÷ and å warning lamps light up in the
instrument cluster.
ATTENTION ASSIST is deactivated.
The self-diagnosis function, for example, may not be complete.
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 Carefully drive on a suitable stretch of road, making slight steer-
ing movements, at a speed above

20 km/h.
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
X Drive on carefully.
X Visit a qualified specialist workshop. Display messages
231
On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions÷
inoperative See
Owner's Manual ESP
®
, BAS, PRE-SAFE ®
, the HOLD function, hill start assist and
ESP ®
trailer stabilisation are not available due to a malfunction.
The adaptive brake lights and COLLISION PREVENTION ASSIST
may also have failed.
In addition, the ÷ and å warning lamps light up in the
instrument cluster.
ATTENTION ASSIST is deactivated.
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 Drive on carefully.
X Visit a qualified specialist workshop. T!
÷
inoperative See
Owner's Manual EBD (electronic brake force distribution), ABS, ESP
®
, BAS, PRE-
SAFE ®
,

the HOLD function, hill start assist and ESP ®
trailer stabi-
lisation are unavailable due to a malfunction.
The adaptive brake lights and COLLISION PREVENTION ASSIST
may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster and a warning tone sounds.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The front and rear wheels could therefore
lock, for example, if you brake hard.
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 Drive on carefully.
X Visit a qualified specialist workshop immediately.232
Display messages
On-board computer and displays

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

Problem Possible causes/consequences and
M Solutions!
The
yellow ABS warning
lamp is lit while the
engine is running. ABS is temporarily unavailable. Therefore, BAS, COLLISION PRE-
VENTION
ASSIST, ESP ®
, EBD (electronic brake force distribution),
PRE-SAFE ®
, the HOLD function, hill start assist, the adaptive brake
lights and ESP ®
trailer stabilisation, for example, are also deacti-
vated.
Possible causes:
R Self-diagnosis is not yet complete.
R the on-board voltage may be insufficient
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The front and rear wheels could therefore
lock, for example, if you brake hard.
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 a risk of an accident.
X Carefully drive on a suitable stretch of road, making slight steer-
ing movements at a speed above 20 km/h.
The functions mentioned above are available again when the
warning lamp goes out.
If the warning lamp is still on:
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
259
On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions֌
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. ESP
®
, BAS, COLLISION PREVENTION ASSIST, PRE-SAFE ®
, the
HOLD function, hill start assist, the adaptive brake lights and
ESP ®
trailer stabilisation are not available due to a malfunction.
ATTENTION ASSIST is deactivated.
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 Visit a qualified specialist workshop. ֌
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. ESP
®
, BAS, PRE-SAFE ®
, the HOLD function, hill start assist and
ESP ®
trailer stabilisation are temporarily unavailable.
The adaptive brake lights and COLLISION PREVENTION ASSIST
may also have failed.
ATTENTION ASSIST is deactivated.
Self-diagnosis is not yet complete.
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 Carefully drive on a suitable stretch of road, making slight steer-
ing movements at a speed above 20 km/h.
The functions mentioned above are available again when the
warning lamp goes out.
If the warning lamp is still on:
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop.262
Warning and indicator lamps in the instrument cluster
On-board computer and displays