Quick update.
Had the car in with MB for diagnostics, and apparently the AC condenser had become "permeable" and was slowly leaking the refrigerant. It wasn't stone chipped or cracked, but had just become porous!
Can't imaging that this is common, but MB covered it all under extended warranty so BIG to MB Tamworth for looking after me.
This is on a 62 plate car.
Had the 3 flashing lights on my SLK55 only a couple of days after buying it..
No Aircon working
Only 2 years old so took it in and they said it just needed a regas which they did under warranty.
I did ask if this was normal to need a regas at only 9700 miles and a little over 2 years old?
They said it was possibly down to the way it was used .!!!
Not too sure on there answer really as cars 10 years old have never needed regassing but hey ho..! See how it goes.
I have this problem too! Iv had my c63 3 months now with 14000 on the clock and the Air Con doesnt work. Going see what the problem is when i send it in for a service in the next few weeks