W211 Aircon won't switch off - any ideas?

[Diesel Benz]

sorry just to clarify.......when i press "auto" on the climatic, the red light on the "ac off" button goes off. when i hit the "ac off" button the red light comes on - but you say this means the ac is actually ON??!!

rushing off to read manual as very confused!

Sorry, I should have searched for some good figures. If the light goes off from "auto", then you must have the old "Economy" light. In this case the light indicates the AC is off.

Owners have been pretty confused with this and that is why the design was changed. It isn't any more an Economy mode light but an "AC on light". In this case the light comes on when you press "auto".

It is very visible from the AC buttons and the text there. I'll see if I can find example figures.

Edited: this is from the current user manual:

 

[s60r]

many thanks.

so if my light is on on the "ac off" button and the air is still refrigerated then there must be a fault?