override the laws of physics. Driving safety
systems are merely aids designed to assist
driving. You are responsible for maintaining
the distance to the vehicle in front, for vehicle
speed, for braking in good time, and for stay- ing in lane. Always adapt your driving style to
suit the prevailing road and weather condi-
tions and maintain a safe distance from the
vehicle in front. Drive carefully.
The driving safety systems described only
work as effectively as possible when there is
adequate contact between the tires and the
road surface. Please pay special attention to
the notes on tires, recommended minimum
tire tread depths, etc. (Y page 300).
In wintry driving conditions, always use winter
tires (M+S tires) and if necessary, snow
chains. Only in this way will the driving safety
systems described in this section work as
effectively as possible. ABS (Anti-lock Braking System)
General information ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the vehi- cle when braking.
The ! ABS warning lamp in the instrument
cluster lights up when the ignition is switched on. It goes out when the engine is running.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 62). G
WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid- ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop. When ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information
on the ABS warning lamp (Y page 230) and
display messages which may be shown in the
instrument cluster (Y page 201).
ABS works from a speed of about 5 mph
(8 km/h) , regardless of road-surface condi-
tions. ABS works on slippery surfaces, even
when you only brake gently.
Braking X
If ABS intervenes: continue to depress the
brake pedal vigorously until the braking sit- uation is over.
X To make a full brake application:
depress the brake pedal with full force.
If ABS intervenes when braking, you will feel a pulsing in the brake pedal.
The pulsating brake pedal can be an indica-
tion of hazardous road conditions, and func-
tions as a reminder to take extra care while
driving. BAS (Brake Assist System)
General information BAS operates in emergency braking situa-
tions. If you depress the brake pedal quickly,
BAS automatically boosts the braking force,
thus shortening the stopping distance.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 62). G
WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of an accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking. Driving safety systems
63Safety Z
Safety systems
Display messages
Possible causes/consequences and
M
MSolutions !÷
Currently Unavail‐ Currently Unavail‐
able See Opera‐ able See Opera‐
tor's Manual tor's Manual ABS (Anti-lock Braking System), BAS (Brake Assist), ESP
®
(Elec-
tronic Stability Program), the HOLD function, RBS (Recuperative
Brake System) and hill start assist are temporarily unavailable.
COLLISION PREVENTION ASSIST PLUS may also have failed.
The !, ÷, åandé (USA only)/ J(Canada only),
warning lamps in the instrument cluster may also light up.
ATTENTION ASSIST is deactivated.
Possible causes are:
R self-diagnosis is not yet complete.
R the on-board voltage may be insufficient.
G WARNING
The braking performance of the electric motor using recuperative braking may be either reduced or not effective. If you do not make
an additional effort to apply the brake yourself, the braking effect may not be sufficient. If necessary, counteract the reduced regen-erative braking effect by applying the brake yourself.
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 stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Carefully drive a short distance on a suitable stretch of road,
making slight steering movements at a speed above 12 mph
(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 Inoperative See
Operator's Manual Operator's Manual ABS, BAS, ESP
®
, the HOLD function, RBS and hill start assist are
not available due to a malfunction.
COLLISION PREVENTION ASSIST PLUS may also have failed.
The !, ÷, å,é(USA only)/ J(Canada only) and
$(USA only)/J(Canada only) warning lamps in the instru-
ment cluster may also light up. Display messages
201On-board computer and displays Z
Display messages
Possible causes/consequences and
M
MSolutions ÷
Inoperative See Inoperative See
Operator's Manual Operator's Manual ESP
®
, BAS, the HOLD function, RBS and hill start assist are not
available due to a malfunction.
COLLISION PREVENTION ASSIST PLUS may also have failed.
The ÷, åandé (USA only)/ J(Canada only) warning
lamps in the instrument cluster may also light up.
ATTENTION ASSIST is deactivated.
G WARNING
The braking performance of the electric motor using recuperative braking may be either reduced or not effective. If you do not make
an additional effort to apply the brake yourself, the braking effect may not be sufficient. If necessary, counteract the reduced regen-erative braking effect by applying the brake yourself.
The brake system continues to function normally, but without the functions listed above.
The braking distance in an emergency braking situation can thus
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Drive on carefully.
X Visit a qualified specialist workshop. 204
Display
messagesOn-board computer and displays
Display messages
Possible causes/consequences and
M
MSolutions T!
÷
Inoperative See Inoperative See
Operator's Manual Operator's Manual EBD (electronic brake force distribution), ABS, BAS, ESP
®
, the
HOLD function, RBS and hill start assist are not available due to a malfunction.
COLLISION PREVENTION ASSIST PLUS may also have failed.
A warning tone sounds.
The ÷, å,!andé (USA only)/J (Canada only)
warning lamps in the instrument cluster may also light up.
G WARNING
The braking performance of the electric motor using recuperative braking may be either reduced or not effective. If you do not make
an additional effort to apply the brake yourself, the braking effect may not be sufficient. If necessary, counteract the reduced regen-erative braking effect by applying the brake yourself.
The brake system continues to function normally, but without the functions listed above. The front and rear 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 stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. F(USA
only)!
(Canada
only)
Turn On the Igni‐ Turn On the Igni‐
tion to Release tion to Release
the Parking Brake the Parking Brake The red
F(USA only)/! (Canada only) indicator lamp lights
up.
You attempted to release the electric parking brake while the igni-
tion was switched off.
X SmartKey: turn the SmartKey to position 1in the ignition lock.
X KEYLESS-GO: switch on the ignition. F(USA
only)!
(Canada
only)
Please Release Please Release
Parking Brake Parking Brake The red
F(USA only)/! (Canada only) indicator lamp
flashes and a warning tone sounds. A condition for automatic
release of the electric parking brake is not fulfilled (Y page 155).
You are driving with the electric parking brake applied.
X Release the electric parking brake manually. The red
F(USA only)/! (Canada only) indicator lamp
flashes and a warning tone sounds.
You are using the electric parking brake for emergency braking
(Y page 155). Display
messages
205On-board computer and displays Z
Display messages
Possible causes/consequences and
M
MSolutions Blind Spot Assist
Blind Spot Assist
Inoperative Inoperative Blind Spot Assist is defective.
The yellow
9indicator lamps also light up in the exterior mir-
rors.
X Visit a qualified specialist workshop. Park Assist Can‐ Park Assist Can‐
celed celed The driver's door is open and the driver's seat belt has not been
fastened.
X Repeat the parking process with the seat belt fastened and the
driver's door closed. You have inadvertently touched the multifunction steering wheel
while steering intervention was active.
X While steering intervention is active, make sure that the multi-
function steering wheel is not touched unintentionally. The vehicle has started to skid and ESP
®
has intervened.
X Use Active Parking Assist again later (Y page 168).Park Park
Assist
Assist Inoper‐
Inoper‐
ative
ative You have just carried out a large number of turning or parking
maneuvers.
Active Parking Assist will become available again after approx-
imately ten minutes (Y
page 168).
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Switch off the drive system and start it again.
If the display message continues to be displayed: X Visit a qualified specialist workshop. PARKTRONIC is defective.
X Visit a qualified specialist workshop. Park Assist Fin‐ Park Assist Fin‐
ished ished The vehicle is parked. A warning tone also sounds.
The display message disappears automatically.220
Display
messagesOn-board computer and displays
Display messages
Possible causes/consequences and
M
MSolutions Cruise Control
Cruise Control
Inoperative Inoperative Cruise control is malfunctioning.
A warning tone also sounds.
X Visit a qualified specialist workshop. Cruise Control Cruise Control
- - - mph - - - mph A condition for activating cruise control has not been fulfilled.
You have tried to store a speed below 20 mph
(30 km/h), for
example.
X If conditions permit, drive faster than 20 mph (30 km/ h)and
store the speed.
X Check the activation conditions for cruise control (Y page 162).Tires
Display messages
Possible causes/consequences and
M MSolutions Please Correct
Please Correct
Tire Pressure Tire Pressure The tire pressure is too low in at least one of the tires, or the tire
pressure difference between the wheels is too great.
X Check the tire pressures at the next opportunity (Y page 307).
X If necessary, correct the tire pressure.
X Restart the tire pressure monitor (Y page 309).Check Tires
Check Tires The tire pressure in one or more tires has dropped significantly.
The wheel position is displayed in the multifunction display.
A warning tone also sounds.
G WARNING
Tire pressures that are too low pose the following hazards:
R they may burst, especially as the load and vehicle speed
increase.
R they may wear excessively and/or unevenly, which may greatly
impair tire 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
maneuvers. Pay attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away (Y page 153).
X Check the tires and, if necessary, follow the instructions for a
flat tire (Y page 280).
X Check the tire pressure (Y page 307).
X If necessary, correct the tire pressure. Display messages
221On-board computer and displays Z