Have a tech check the level of the freon.
If you do it yourself, the readings should be as follows.
Clean the window on the sight glass of the drier.
Turn on the A>C and look into the glass. IF bubbles are seen, the system is low/ The bubbles should come in for a few seconds then the glass should clear for a while.
This cycle is the key to a properly charged system.
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS