The display informs you if the AdBlue level is too low or if a system malfunction occurs.
Low AdBlue level
You will be informed if the amount of AdBlue in the tank falls below a certain level:
AdBlue 
2,400 km Refill AdBlue. See owner's manual
2,400 km Refill AdBlue. See owner's manual
This message tells you the maximum distance that you can drive with the remaining amount of AdBlue. Refill AdBlue.
AdBlue 
1,000 km Refill AdBlue! No restart in 1000 km! See owner's manual
1,000 km Refill AdBlue! No restart in 1000 km! See owner's manual
This message tells you the maximum distance that you can drive with the remaining amount of AdBlue. Refill AdBlue. Otherwise, after driving the maximum distance and switching off the engine, you will not be able to restart the car.
AdBlue 
0 km Refill AdBlue! No restart! See owner's manual
0 km Refill AdBlue! No restart! See owner's manual
This message appears when there is no more AdBlue left in the tank. Refill AdBlue. Otherwise, you will not be able to restart the car after you switch off the engine.
When the AdBlue in the tank reaches the minimum level, you must add AdBlue
Link.
Filling the wrong fluid / system fault
If you fill the AdBlue tank with a fluid other than AdBlue and the system detects that the wrong fluid has been added or there is a system fault, a driver message will appear.
AdBlue 
1,000 km AdBlue: system fault. No restart in 1000 km! See owner's manual
1,000 km AdBlue: system fault. No restart in 1000 km! See owner's manual
This message tells you the maximum distance that you can drive. Drive to a qualified workshop and have the fault rectified. Otherwise, after driving the maximum distance and switching off the engine, you will not be able to restart the car.
AdBlue 
0 km AdBlue: system fault. No restart! See owner's manual
0 km AdBlue: system fault. No restart! See owner's manual
This message appears if the system detects that the tank has been filled with the wrong fluid or if there is a system fault. Drive to the nearest qualified workshop without delay and have the fault rectified. Otherwise, you will not be able to restart the car after you switch off the engine.