David:
Behind the driver's side headlight there is a small black metal AC fitting that has a little round window in the top where you can see Freon circularing. I am not sure where it is located on yours. One sign of a leak and low freon levels is iff you see bubbles through this window when the AC is turned on. Good luck!

__________________
John

2003 Firemist Red/grey leather SL 500
2015 Palladium Silver/black mbtex GLK 350
1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)

Click to see 87 300E