Driving systems

Display messages Possible causes/consequences and Solutions
Based on specific criteria, ATTENTION ASSIST has determined that the Based on specific criteria, ATTENTION ASSIST has determined that the driver is tired or paying less attention. A warning tone also sounds.
– If necessary, take a break.
During long journeys, take regular breaks in good time so you get enough rest.
ATTENTION ASSIST has failed. ATTENTION ASSIST has failed.
– Visit a qualified specialist workshop.
You cannot change the vehicle level. Possible causes are: You cannot change the vehicle level. Possible causes are:
- you are driving too fast for the selected vehicle level.
- you are towing a trailer.
- the trailer-coupling socket is being used, e.g. for a bicycle rack.
– Drive more slowly and then select the desired vehicle level again.
– Observe the notes on towing a trailer.
You have selected a higher vehicle level. The compressor first needs You have selected a higher vehicle level. The compressor first needs to cool down because of frequent level changes.
– Drive in a manner appropriate for the current vehicle level.
– Make sure that there is sufficient ground clearance.
– Allow the compressor to cool down.
When the compressor has cooled down, the display message disappears. The vehicle then continues rising to the selected level.
AIRMATIC is malfunctioning. AIRMATIC is malfunctioning.
– Drive in a manner appropriate for the current vehicle level, but no faster than 50 mph (80 km/h).
– Make sure that there is sufficient ground clearance.
– Have the vehicle checked at a qualified specialist workshop.
The Active Curve System is faulty. The vehicle's handling characteristics may be affected.
– Do not drive faster than 50 mph (80 km/h).
– Have the vehicle checked at a qualified specialist workshop.
Risk of accidentThe Active Curve System is faulty. The vehicle's handling characteristics are severely impaired. Risk of accident

The Active Curve System is faulty. The vehicle's handling characteristics are severely impaired.
In addition, the vehicle level display appears between the vehicle icon and the display message, and a warning tone sounds.
– Do not drive faster than 12 mph (20 km/h).
– Adjust your driving style to the altered handling characteristics.
– Visit a qualified specialist workshop immediately.
DSR (Downhill Speed Regulation) is deactivated due to a DSR (Downhill Speed Regulation) is deactivated due to a malfunction.
– Have DSR checked at a qualified specialist workshop.
The HOLD function is deactivated. The vehicle is skidding. The HOLD function is deactivated. The vehicle is skidding.
A warning tone also sounds.
– Reactivate the HOLD function later.
The radar sensor system is deactivated. The radar sensor system is deactivated.
– Switch on the radar sensor system.
Lane Keeping Assist or Active Lane Keeping Assist is deactivated and Lane Keeping Assist or Active Lane Keeping Assist is deactivated and temporarily inoperative. Possible causes are:
- the windshield in the camera's field of vision is dirty.
- visibility is impaired due to heavy rain, snow or fog.
- there are no lane markings for a longer period.
- the lane markings are worn, dark or covered, e.g. by dirt or snow.
If the display message does not disappear:
– Pull over and stop the vehicle safely as soon as possible, paying attention to road and traffic conditions.
– Apply the electric parking brake.
– Clean the windshield.
If the system detects that the camera is fully operational, the display message disappears.
Lane Keeping Assist or Active Lane Keeping Assist is operational again.
Lane Keeping Assist or Active Lane Keeping Assist is defective. Lane Keeping Assist or Active Lane Keeping Assist is defective.
– Visit a qualified specialist workshop.
Blind Spot Assist or Active Blind Spot Assist is temporarily Blind Spot Assist or Active Blind Spot Assist is temporarily inoperative. Possible causes are:
- you have established the electrical connection between the trailer and your vehicle.
- the sensors are dirty.
- function is impaired due to heavy rain or snow.
- the radar sensor system is outside the operating temperature range.
- 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 also light up in the exterior mirrors. indicator lamps also light up in the exterior mirrors.
– When towing a trailer, confirm the display message with If you are driving without a trailer and the display message does not.
If you are driving without a trailer and the display message does not disappear:
– Pull over and stop the vehicle safely as soon as possible, paying attention to road and traffic conditions.
– Apply the electric parking brake.
– Clean the sensors.
– Restart the engine.
If the system detects that the sensors are fully operational, the display message disappears.
Blind Spot Assist or Active Blind Spot Assist is operational again.
Blind Spot Assist or Active Blind Spot Assist is defective. Blind Spot Assist or Active Blind Spot Assist is defective.
The yellow also light up in the exterior mirrors. indicator lamps also light up in the exterior mirrors.
– Visit a qualified specialist workshop.
The driver's door is open and the driver's seat belt has not been The driver's door is open and the driver's seat belt has not been fastened.
– 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.
– While steering intervention is active, make sure that the multifunction steering wheel is not touched unintentionally.
The vehicle has started to skid and ESP® has intervened.
– Use Active Parking Assist again later.
You have just carried out a large number of turning or parking You have just carried out a large number of turning or parking maneuvers.
Active Parking Assist will become available again after approximately 10 minutes.
– Pull over and stop the vehicle safely as soon as possible, paying attention to road and traffic conditions.
– Switch off and restart the engine.
If the display message continues to be displayed:
– Visit a qualified specialist workshop.
PARKTRONIC is defective.
– Visit a qualified specialist workshop.
The vehicle is parked. A warning tone also sounds. The vehicle is parked. A warning tone also sounds.
The display message disappears automatically.
DISTRONIC PLUS has been deactivated. If it was deactivated DISTRONIC PLUS has been deactivated. If it was deactivated automatically, a warning tone also sounds.
DISTRONIC PLUS is operational again after having been temporarily DISTRONIC PLUS is operational again after having been temporarily unavailable. You can now reactivate DISTRONIC PLUS.
DISTRONIC is deactivated and temporarily inoperative. Possible DISTRONIC is deactivated and temporarily inoperative. Possible causes are:
- the DISTRONIC PLUS cover in the radiator grille is dirty.
- function is impaired due to heavy rain or snow.
- the sensors in the bumpers are dirty.
- 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 system is outside the operating temperature range.
- The on-board voltage is too low.
A warning tone also sounds.
If the display message does not disappear:
– Pull over and stop the vehicle safely as soon as possible, paying attention to road and traffic conditions.
– Apply the electric parking brake.
– Clean the DISTRONIC PLUS cover in the radiator grille.
– Clean the bumpers.
– Restart the engine.
If the system detects that the sensors are fully operational, the display message disappears.

DISTRONIC is operational again.
DISTRONIC PLUS is defective. BAS PLUS (Brake Assist PLUS) and DISTRONIC PLUS is defective. BAS PLUS (Brake Assist PLUS) and PRE-SAFE® Brake may be inoperative as well.
A warning tone also sounds.
– Visit a qualified specialist workshop.
You have depressed the accelerator pedal. DISTRONIC PLUS is no You have depressed the accelerator pedal. DISTRONIC PLUS is no longer controlling the speed of the vehicle.
– Take your foot off the accelerator pedal.
An activation condition for DISTRONIC PLUS is not fulfilled. An activation condition for DISTRONIC PLUS is not fulfilled.
– Check the activation conditions for DISTRONIC PLUS.
Cruise control is defective. Cruise control is defective.
– Visit a qualified specialist workshop.
A condition for activating cruise control has not been fulfilled. A condition for activating cruise control has not been fulfilled.
You attempted to save a speed of less than 20 mph (30 km/h).
– If the situation allows, drive faster than 20 mph (30 km/h) and save the speed.
– Check the activation conditions for cruise control.
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