[91must50]

Im trying to get my AC to work on my 91gt. when i run a wire from the battery to the compresser it turns on.otherwise it doesn't. im wondering if there is an in-line fuse that goes to the AC compresser. if so where is it? the guy who sold it to me said the AC didn't work because it had different pulleys or something and said i needed the original AC clutch pully. so i bought it but havent installed it yet because i got it to work when i rigged it with the wire to battery so im guessing its a bad wire, or fuse somewhere... any thoughts or help will be much appreciated,ty

[matt17]

does the compressor cycle on and off when you have your defrost on?if not is a wiring issue!if the freon is to low the compressor has a low presure switch that wont let it run but will cycle on and of with the defrost on! good luck

[STINGREY]

check the ac relay,passenger side just below the air meter.

[Quad]

It should never run if it's low on refridgerant regardless of what you do besides straightwire it. The low pressure switch is inline to any circuit that try's to energize the clutch. A clutch that engages with low or no coolant will end up in a seized compressor and one burnt belt. Now that's not saying something can't be altered to make it function differently.

However the best bet is when A/C Compressors haven't been used in a while you can pretty much bet there is no refridgerant in them. R12 Will be expensive and unless you know how to retro fit your car you will be paying some serious money for someone else to do it. It's gonna cost you a arm and a leg either way you look at it really.. either the retro fit or R12. However if the refridgerant isn't low it's a pretty simple circuit to diagnose.. but you will need a wiring diagram. Some vehicles use WOT's, some the computer grounds the circuit some don't, some use High side swithes, and relays etc. I don't know what comes on your car but to electrically fix it you'll need a wiring diagram and some kind of component location diagram. If it's low in refridgerant find the leak or you'll be wasting your money. There are some alternatives out there that replicate the function of R12. However I don't endorse anyone using them even though I have myself. Two reasons is I can't guarantee the life of any component when it's not designed for a specific refridgerant and when other shops have to deal with the vehicle for some reason some like freeze 12 actually contain propane and such. It's just not that great of an idea unless your the only person that will ever be working on it.