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Display messagesPossible causes/consequences and M Solutionsb
Check Left Daytime
Running
Light or Check
Right Daytime
Running LightThe left or right-hand daytime running lamp is defective.XCheck whether you are permitted to change the bulb yourself
( Y page 256).
or
XVisit a qualified specialist workshop.b
Active Headlamps
InoperativeThe active light function is defective.XVisit a qualified specialist workshop.b
Malfunction See
Oper. ManualThe exterior lighting is defective.XVisit a qualified specialist workshop.b
AUTO Lamp Function
InoperativeThe light sensor is defective.XVisit a qualified specialist workshop.
USA only:
XSwitch off the daytime running lamps in the on-board computer
( Y page 349).XSwitch the lights on and off using the light switch.b
Please Switch Off
LightsThe lights are still switched on when you leave the vehicle. A
warning tone also sounds.XTurn the light switch to $ or c .
or
XIf the rear fog lamp is switched on: press the light switch in to
the stop.Adaptive High-beam
Assist InoperativeAdaptive Highbeam Assist is faulty.XVisit a qualified specialist workshop.370Display messagesOn-board computer and displays
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Driving systemsDisplay messagesPossible causes/consequences and M SolutionsÀ
Attention Assist:
Drowsiness
DetectedBased 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.Á
Night View Assist
InoperativeNight View Assist Plus is defective.XVisit a qualified specialist workshop.Á
Night View Assist
Currently
UnavailableThe temperature of the camera is too high.XWait until you see the Night View Assist Available
Again display message.
You can also:
XFold the camera cover down ( Y page 432).XAdjust the air distribution of the automatic air conditioning
upwards.Á
Night View Assist
Lights Must Be Set
To AUTO or ONA condition for activating Night View Assist Plus has not been
fulfilled.XTurn the light switch to c or L .Á
Night View Assist
Not In Reverse GearA condition for activating Night View Assist Plus has not been
fulfilled.XShift the transmission to P, N or D.Á
Night View Assist
Lights ON or AUTO,
Not in R GearA condition for activating Night View Assist Plus has not been
fulfilled.XTurn the light switch to c or L .XShift the transmission to P, N or D.Display messages375On-board computer and displaysZ
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Display messagesPossible causes/consequences and M SolutionsRadar Sensors
Deactivated See
Oper. ManualThe radar sensor system is deactivated.XSwitch on the radar sensor system ( Y page 350).Active Lane
Keeping Assist
Currently
Unavailable See
Oper. ManualActive Lane Keeping Assist is deactivated and temporarily
inoperative. Possible causes are:
R the windshield in the camera's field of vision is dirty.
R visibility is impaired due to heavy rain, snow or fog.
R there are no lane markings for a longer period.
R the lane markings are worn, dark or covered, e.g. by dirt or snow.
If the display message does not disappear:XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XSecure the vehicle against rolling away ( Y page 289).XClean the windshield.
If the system detects that the camera is fully operational, the
display message disappears.
Active Lane Keeping Assist is operational again.
Active Lane
Keeping Assist
InoperativeActive Lane Keeping Assist is defective.XVisit a qualified specialist workshop.378Display messagesOn-board computer and displays
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Display messagesPossible causes/consequences and M SolutionsActive Blind Spot
Assist
Currently
Unavailable See
Operator's ManualActive Blind Spot Assist is temporarily inoperative. Possible
causes are:
R the sensors are dirty.
R function is impaired due to heavy rain or snow.
R the radar sensor system is outside the operating temperature
range.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio
stations or other sources of electromagnetic radiation.
The yellow 9 indicator lamps also light up in the exterior
mirrors.
If the display message does not disappear:
If the display message does not disappear:XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XSecure the vehicle against rolling away ( Y page 289).XClean the sensors ( Y page 431).XRestart the engine.
If the system detects that the sensors are fully operational, the
display message disappears.
Active Blind Spot Assist is operational again.
Active Blind Spot
Assist
InoperativeActive Blind Spot Assist is defective.
The yellow 9 indicator lamps also light up in the exterior
mirrors.XVisit a qualified specialist workshop.Parking Guidance
InoperativeParking Guidance is malfunctioning ( Y page 315).XRestart the engine.
If the display message continues to be displayed:
XVisit a qualified specialist workshop.Display messages379On-board computer and displaysZ
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Display messagesPossible causes/consequences and M SolutionsDISTRONIC PLUS
Currently
Unavailable See
Operator's ManualDISTRONIC is deactivated and temporarily inoperative. Possible
causes are:
R the DISTRONIC PLUS cover in the radiator trim is dirty
R function is impaired due to heavy rain or snow.
R the sensors in the bumpers are dirty.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio
stations 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.
If the display message does not disappear:XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XSecure the vehicle against rolling away ( Y page 289).XClean the DISTRONIC PLUS cover in the radiator trim
( Y page 431).XClean the bumpers ( Y page 431).XRestart the engine.
If the system detects that the sensors are fully operational, the
display message disappears.
DISTRONIC is operational again.
DISTRONIC PLUS
InoperativeDISTRONIC PLUS is defective. BAS PLUS (Brake Assist PLUS) and
PRE-SAFE ®
Brake may be inoperative as well.
A warning tone also sounds.XVisit a qualified specialist workshop.DISTRONIC PLUS
OverrideYou have depressed the accelerator pedal. DISTRONIC PLUS is no
longer controlling the speed of the vehicle.XRemove your foot from the accelerator pedal.DISTRONIC PLUS
--- mphAn activation condition for DISTRONIC PLUS is not fulfilled.XCheck the activation conditions for DISTRONIC PLUS
( Y page 298).Display messages381On-board computer and displaysZ
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Display messagesPossible causes/consequences and M SolutionsCruise Control
InoperativeCruise control is defective.
A warning tone also sounds.XVisit a qualified specialist workshop.Cruise Control
--- mphA condition for activating cruise control has not been fulfilled.
You have tried to store a speed below 20 mph (30 km/h), for
example.XIf conditions permit, drive faster than 20 mph (30 km/h) and
store the speed.XCheck the activation conditions for cruise control
( Y page 296).
Tires
Display messagesPossible causes/consequences and M Solutionstire pressures
displayed after
driving a few
minutesThe tire pressure monitor is measuring the tire pressure.XDrive on.
The tire pressures appear in the multifunction display after you
have been driving for a few minutes.tire press. monitor
inoperativeThe tire pressure monitor is faulty.XVisit a qualified specialist workshop.tire press. monitor
inoperative No
wheel sensorsThe wheels mounted do not have a suitable tire pressure sensor.
The tire pressure monitor is deactivated.XMount wheels with suitable tire pressure sensors.
The tire pressure monitor is activated automatically after driving
for a few minutes.382Display messagesOn-board computer and displays