I have a 94 80 series with 165K miles. The AC belt began squealing about 2 weeks ago. After removing the belt, it was obvious that the AC Compressor Clutch pulley was not turning(seized). My question is, can a clutch fail in such a way that it seizes? Or is the seized pulley a sure sign that the compressor has locked up? Obviously, one is a lot more expensive than the other. Thanks in advance.