We don't usually drive it in the summer. I have the feeling that it gradually stopped working but I could be wrong. It's my wife's car (she only lets me drive it when it needs gas!). Also, in our climate (Calgary, Canada) the EC setting is all we need most of the time.

When we tried to charge it (with friendly backyard mechanic) it showed about 100 psi but seemed to be all air - no fog, no condensation, no cooling of the skin as it escaped. Learned a bit since then. Took it to an A/C place who checked it out and re-charged it but couldn't do more because they are not MB experts. They powered the compressor directly to make sure everything was working before charging. The pressure switch seems to be OK so I am hoping that wasn't a waste of money!