There really is no alternative but to take it to a trustworthy air con dealer for an evacuate and refil. Then checks can be made to see why yours stopped working. Could be a holed condenser radiator or compressor shaft seal - this should be revealed as a fluorescent die is added to detect leaks with a fluorescent lamp. Could be that it just needs this vital service. Cost me around £70.00 at a non BMW garage.
Don't be tempted to waste money on aerosol air con aids you can get from a certain national car & cycle parts dealer as you can make it worse (as I did) where my compressor stalled and nearly broke the driving belt. A replacement compressor is really expensive and you will still need an evacuate & regas.
xyzbird
October 2008
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