Thanks Guy's: I Did as you suggested and jumpered the low pressure sensor on the AC and the compressor kicked in. It looks like I just need a re-charge and have talked to a couple of shops near where I live and have gotten quotes for R12 from $59 lb. to $159 lb. to recharge and one guy told me that I likely have a leak and should have it converted to R134 and the other says that the old systems just run low after several years. The bottom line it that I plan to take it in next week and if all it needs is a re-charge I will only be out $130-$160 unless there is a leak. What is your experience, are these systems prone to have leakes or is it likely that a re-charge will do it????? Thanks again for the help...PS: I'm still a few weeks out from having time to unhook the CAT.. I'll keep you posted....