Active Lane Keeping Assist does not detect
traffic situations or road users. An
inappropriate brake application may be
interrupted at any time if you:
R steer slightly in the opposite direction.
R use a turn signal.
R clearly brake or accelerate.
A lane-correcting brake application is
interrupted automatically if:
R a driving safety system intervenes, e.g.
ESP ®
, PRE-SAFE ®
Brake or Active Blind
Spot Assist.
R lane markings can no longer be recognized.
Switching on Active Lane Keeping AssistXSwitch on Active Lane Keeping Assist using
the on-board computer ( Y page 225).
Symbol : appears in the multifunction
display.
If your speed exceeds 40 mph (60 km/h)
and lane markings are detected,
symbol : is highlighted. Active Lane
Keeping Assist is ready for use.212Driving systemsDriving and parking
XTo show menu bar ;: press the =
or ; button on the steering wheel.
The following messages may appear in the
multifunction display:
X j YParking Guidance ( Y page 195)èRear window wiper ( Y page 125)_Adaptive Highbeam Assist
( Y page 118)ÀATTENTION ASSIST ( Y page 199)ÃLane Keeping Assist ( Y page 205) or
Active Lane Keeping Assist
( Y page 210)HOLDHOLD function ( Y page 187)ÄPRE-SAFE ®
Brake ( Y page 69)Displays and operation217On-board computer and displaysZ
XTo activate: press a again.
The å warning lamp in the instrument
cluster goes out.
Activating/deactivating PRE-SAFE ®
Brake
PRE-SAFE ®
Brake is only available in vehicles
with DISTRONIC PLUS.
XPress the = or ; button on the
steering wheel to select the DriveAssist
menu.XPress 9 or : to select PRE-SAFE
Brake .XPress a.
The current selection is displayed.XTo activate/deactivate: press a
again.
When PRE-SAFE ®
Brake ( Y page 69) is
activated, the multifunction display shows
the Ä symbol as long as the HOLD
function is not activated ( Y page 187).
Vehicles with Parking Guidance: if
PARKTRONIC is activated and you are driving
at a speed under 22 mph (35 km/h) the j
symbol for Parking Guidance is displayed
instead of the Ä symbol.
Activating/deactivating ATTENTION
ASSIST
XPress the = or ; button on the
steering wheel to select the DriveAssist
menu.XPress the 9 or : button to select
Attention Asst. .XPress a.
The current selection is displayed.XTo activate/deactivate: press a
again.
When ATTENTION ASSIST ( Y page 199) is
activated, the À symbol appears in the
multifunction display when the ignition is on.
Activating/deactivating Blind Spot
Assist
You can use the Blind Spot Asst. function
to activate or deactivate Blind Spot Assist
( Y page 203) or Active Blind Spot Assist
( Y page 207).
XPress = or ; on the steering wheel
to select the DriveAssist menu.XPress 9 or : to select Blind Spot
Asst. .XPress a.
If the function is activated, the monitored
areas are shown in red in the multifunction
display.XTo activate/deactivate: press a
again.
Activating/deactivating Lane Keeping
Assist
You can use the Lane Keep. Asst. function
to activate/deactivate Lane Keeping Assist
( Y page 205) or Active Lane Keeping Assist
( Y page 210).
XPress the = or ; button on the
steering wheel to select the DriveAssist
menu.XPress the 9 or : button to select
Lane Keep. Asst. .XPress a.
If the function is activated, the road
markings are shown in red in the
multifunction display.XTo activate/deactivate: press a
again.
If Lane Keeping Assist or Active Lane keeping
Assist is activated, the multifunction display
shows the à symbol when the ignition is
switched on.
Menus and submenus225On-board computer and displaysZ
Display messagesPossible causes/consequences and M Solutions$ (USA
only) J (Canada
only)
Release Parking
BrakeYou are driving with the parking brake applied. A warning tone also
sounds.XRelease the parking brake.$ (USA
only) J (Canada
only)
Check Brake Fluid
LevelGRisk of accident
There is not enough brake fluid in the brake fluid reservoir.
Additionally, the red $ (USA only)/ J (Canada only)
warning lamp lights up in the instrument cluster and a warning
tone sounds.
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.XEngage the parking brake.XConsult a qualified specialist workshop.XDo not add brake fluid. This will not rectify the malfunction.GWARNING
Driving with the message Check Brake Fluid Level displayed can result in an accident. Have
your brake system checked immediately.
Do not add brake fluid before checking the brake system. Overfilling the brake fluid reservoir can
result in spilling brake fluid on hot engine parts and the brake fluid catching fire. You can be
seriously burned.
Display messagesPossible causes/consequences and M SolutionsG
Tele Aid
InoperativeUSA only: one or more of the main functions in the mbrace system
are malfunctioning.
Canada only: one or more of the main functions of the TELEAID
system are malfunctioning.XUSA only: have the mbrace system checked at a qualified
specialist workshop.XCanada only: have the TELEAID system checked at a qualified
specialist workshop.PRE-SAFE
Inoperative See
Operator's ManualGRisk of injury
Important functions of PRE-SAFE ®
have failed. All other occupant
safety systems, e.g. air bags, remain available.
XVisit a qualified specialist workshop immediately.Display messages237On-board computer and displaysZ
Display messagesPossible causes/consequences and M SolutionsFront Passenger
Airbag Enabled
See Operator's
ManualThe front-passenger air bag is enabled during the journey, even
though:
R a child, a small adult or an object weighing less than the
system's weight threshold is located on the front-passenger
seat.
R the front-passenger seat is unoccupied.
The system may detect objects or forces applying additional
weight on the seat.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XSwitch off the ignition.XOpen the front-passenger door.XRemove the child and the child restraint system from the front-
passenger seat.XIf necessary, secure the child in a child restraint system on a
suitable rear seat.XMake sure that there are no objects on the seat adding to the
weight.
The system may otherwise detect the additional weight and
interpret the seat occupant's weight as greater than it actually
is.XKeep the seat unoccupied, close the front-passenger door and
switch on the ignition.
Observe the 45(Y page 44) indicator lamp and the
multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 45 indicator lamp must light up and remain lit. When
the indicator lamp is on, OCS ( Y page 44) has deactivated the
front-passenger air bag.
R the Front Passenger Airbag Enabled See Operator's
Manual or Front Passenger Airbag Disabl'd See
Operator's Manual display messages must not appear in the
multifunction display. Wait for a period of at least 60 seconds
until the necessary system checks have been completed and to
make sure that the display messages do not appear in the
multifunction display.
If these conditions are fulfilled, the front-passenger seat can be
occupied again. Whether the 45 indicator lamp remains lit
or goes out depends on how OCS classifies the occupant.
If the conditions are not fulfilled, the system is not operating
correctly.
240Display messagesOn-board computer and displays
Display messagesPossible causes/consequences and M SolutionsXVisit a qualified specialist workshop immediately.GWARNING
If the 45 indicator lamp remains off even after performing the above corrective steps, do
not have any children 12 years old and under and other small individuals use the front-passenger
seat until the system has been repaired.
Display messagesPossible causes/consequences and M SolutionsFront Passenger
Airbag Disabl'd
See Operator's
ManualThe front-passenger air bag is deactivated during the journey even
though an adult or a person larger than a certain size is occupying
the front-passenger seat. If additional forces are applied to the
seat, the system may interpret the occupant's weight as lower
than it actually is.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XSwitch off the ignition.XHave the occupant get out of the vehicle.XKeep the seat unoccupied, close the front-passenger door and
switch on the ignition.
Observe the 45(Y page 44) indicator lamp and the
multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 45 indicator lamp must light up and remain lit. When
the indicator lamp is on, OCS ( Y page 44) has deactivated the
front-passenger air bag.
R the Front Passenger Airbag Enabled See Operator's
Manual or Front Passenger Airbag Disabled See
Operator's Manual display messages must not appear in the
multifunction display. Wait for a period of at least 60 seconds
until the necessary system checks have been completed and to
make sure that the display messages do not appear in the
multifunction display.
If these conditions are fulfilled, the front-passenger seat can be
occupied again. Whether the 45 indicator lamp remains lit
or goes out depends on how OCS classifies the occupant.
If the conditions are not fulfilled, the system is not operating
correctly.
XVisit a qualified specialist workshop immediately.Display messages241On-board computer and displaysZ
Driving systemsDisplay messagesPossible causes/consequences and M SolutionsÀ
Attention Assist:
Pause!Based on specific criteria, ATTENTION ASSIST has determined that
the driver is tired or paying less attention. A warning tone also
sounds.XIf necessary, take a break.
During long journeys, take regular breaks in good time so you get
enough rest.
À
Attention Assist
InoperativeATTENTION ASSIST has failed.XVisit a qualified specialist workshop.¨
Vehicle RisingYour vehicle is adjusting to the level you have selected.¨
Vehicle Rising
Please Wait The vehicle level is too low when the vehicle is stationary. A
warning tone also sounds.XDo not pull away.
The vehicle level is set when the display message disappears.¨
Pull Over Car Too
LowYou have pulled away while the vehicle level is still too low.
AIRMATIC sets the vehicle to the selected level after a short
period.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XApply the parking brake.XWait until the display message disappears before pulling away.GRisk of accident
AIRMATIC is defective. A warning tone also sounds.
XDo not drive faster than 50 mph (80 km/h).XMake only slight steering movements. Otherwise, the front
fender or the tires could be damaged if the steering movement
is too large.XListen for scraping sounds.XPull over and stop the vehicle safely, paying attention to road
and traffic conditions, and select a higher vehicle level.
Depending on the malfunction, it may be possible to raise the
vehicle.XVisit a qualified specialist workshop.Display messages249On-board computer and displaysZ
Display messagesPossible causes/consequences and M Solutionsh
Check Tire PressureGRisk of accident
The tire pressure in one or more tires has dropped significantly.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XIf necessary, change a wheel ( Y page 370).XCheck the tire pressure. If necessary, correct the tire pressure
( Y page 355).h
Correct Tire
PressureThe tire pressure is too low in at least one of the tires or the tire
pressure difference between the wheels is too great.XCheck the tire pressures at the next opportunity. If necessary,
correct the tire pressure ( Y page 355).
Vehicle
Display messagesPossible causes/consequences and M SolutionsShift to 'P' or 'N'
to Start EngineYou have attempted to start the engine with the transmission in
position R or D.XShift the transmission to position P or N.Auxiliary Battery
MalfunctionThe auxiliary battery for the automatic transmission is no longer
being charged.XVisit a qualified specialist workshop.Apply Brake to
Shift from 'P' You have attempted to move the transmission selector lever to
position D, R or N without depressing the brake pedal.XDepress the brake pedal.Door Open
Vehicle Not in 'P'The driver's door is open and the transmission is in position R, N
or D.
A warning tone also sounds.XShift the transmission to position P.XApply the parking brake.Display messages257On-board computer and displaysZ