See also:

Screw thread
Push out the cover by pressing on the top edge. ...

Checking the coolant level
1. Do not open the hood until the engine has cooled down. 2. Turn the expansion tank cap counterclockwise slightly to allow any accumulated pressure to escape; then continue turning to open. ...

BMW maintenance system
BMW maintenance system The maintenance system provides information on required maintenance measures and thus provides support in maintaining road safety and the operational reliability of the ...