intern8tion9l Posted July 5, 2007 Report Posted July 5, 2007 alright i did do a search first....but here's the problem: the a/c compressor won't come on using the interior controls. however, if i jusp the relay it will. a mechanic friend of mine told me that the a/c system needs a signal from the IAT to be able to kick on....is this true? i disconnected the IAT from the ecm when i did the swap as it used the same pin as the wastegate actuator solenoid. i can rewire it if this is the actual problem. thoughts? Quote
cutty Posted July 5, 2007 Report Posted July 5, 2007 the compressor needs a certain amount of freon in the system for it to kick on, so it might just need re-filled. Quote
GPX Posted July 5, 2007 Report Posted July 5, 2007 Hey, I think I have this same problem! All my interior controls seem to work and the AC light even comes on, but the clutch never kicks in with the accompanying dimming and loss of power, and of course under the hood, it's clear that the clutch is not engaging. The only problem with my case is that I had this problem before my motor swap, but that doesn't mean it's not caused by the same problem. It would be nice to have some AC every now and again. How would I go about actuating this relay? Quote
Addicted To Boost Posted July 5, 2007 Report Posted July 5, 2007 You guys need more freon in your systems. If an AC system doesn't have enough freon in it, the ac compressor will refuse to turn on. Thats how it works. Quote
Crazy K Posted July 5, 2007 Report Posted July 5, 2007 You guys need more freon in your systems. If an AC system doesn't have enough freon in it, the ac compressor will refuse to turn on. Thats how it works. exactly. Quote
slick Posted July 5, 2007 Report Posted July 5, 2007 Gah, I hate the usage of Freon. It's refrigerant! Quote
slick Posted July 5, 2007 Report Posted July 5, 2007 IIRC, his car is an 89 International, hence his SN. Originally, his vehicle would be equipped with R-12. If it is still equipped, and has not been converted, hit up ebay for Freeze 12. If it has been converted, go to the parts store and buy more refrigerant. Quote
Crazy K Posted July 5, 2007 Report Posted July 5, 2007 IIRC, his car is an 89 International, hence his SN. Originally, his vehicle would be equipped with R-12. If it is still equipped, and has not been converted, hit up ebay for Freeze 12. If it has been converted, go to the parts store and buy more refrigerant. I know that! LOL I convert mine to R134. R134 is your friend! besides, I checked, the r134 and r12 cars use the same compressor, evaporator and everything, except the pipe has a different fitting. Quote
Addicted To Boost Posted July 5, 2007 Report Posted July 5, 2007 I bought 3 cans of Freeze 12 off Ebay for $20+shipping. Its pretty inexpensive and much colder than R-134. Quote
Crazy K Posted July 5, 2007 Report Posted July 5, 2007 I bought 3 cans of Freeze 12 off Ebay for $20+shipping. Its pretty inexpensive and much colder than R-134. touche! what else do you need to install it in your car? Quote
19Cutlass94 Posted July 5, 2007 Report Posted July 5, 2007 yeah inexpensive if the seller doesnt know what he/she has... the last can of r12 that we sold at work was $60 something for a 12oz can... r12 is not cheap anymore. Quote
Crazy K Posted July 5, 2007 Report Posted July 5, 2007 yeah inexpensive if the seller doesnt know what he/she has... the last can of r12 that we sold at work was $60 something for a 12oz can... r12 is not cheap anymore. you're confusing freeze 12 and r-12! Quote
intern8tion9l Posted July 5, 2007 Author Report Posted July 5, 2007 guys the system is fine. completely full of 134a. installed a new condenser last year. had it pressure tested and recharged. i confirmed this season that the system is still 100% full. so its got to be electrical. my biggest question was the truth in what i heard about the IAT Quote
slick Posted July 5, 2007 Report Posted July 5, 2007 No, there is not truth about it being controlled by the IAT to my understandings. The only readings it looks for are sufficient pressure, and asking to be turned on via the switch on the inside of the vehicle. You can test the system by giving the compressor 12v if you need to. Quote
cutlassdude96 Posted July 6, 2007 Report Posted July 6, 2007 I had my MAF and IAT disconnected while trying to recharge my ac and the compressor didnt come on. re hook them back up and it came on Quote
Crazy K Posted July 6, 2007 Report Posted July 6, 2007 now... there is one other issue, which is whether or not our cars are designed to disable the compressor when the temp is too cold, and with the IAT disconnected it can't tell how cold it is! could be. hmm Quote
slick Posted July 6, 2007 Report Posted July 6, 2007 now... there is one other issue, which is whether or not our cars are designed to disable the compressor when the temp is too cold, and with the IAT disconnected it can't tell how cold it is! could be. hmm If that is the case, then why can you turn on the AC in the winter? Quote
Crazy K Posted July 6, 2007 Report Posted July 6, 2007 now... there is one other issue, which is whether or not our cars are designed to disable the compressor when the temp is too cold, and with the IAT disconnected it can't tell how cold it is! could be. hmm If that is the case, then why can you turn on the AC in the winter? Have you verified that the A/C clutch was engaged? I did say whether or not... I know some newer GM cars disable the compressor below a set temp to prevent system damage. - my parents rented a buck with a faulty sensor in arizona in july, it had a bad sensor and thought it was cold outside, so it disabled the A/C. Quote
slick Posted July 6, 2007 Report Posted July 6, 2007 I know that my AC on several GM vehicles that I have owned will kick on in the winter. In fact, it says in my owners manual to turn it on so the o-rings don't dry out. Quote
1990lumina Posted July 6, 2007 Report Posted July 6, 2007 The compressor in my Lumina runs all winter when the Defrost is on. Quote
99RegalGS Posted July 6, 2007 Report Posted July 6, 2007 Many GM systems will not use the A/C compressor is the temp is below ~40*F, that is unless you hit defrost. Then the compressor kicks on no matter what. Anyway, back to topic.... If you know the system is fully charged, and the compressor is inop. I would check the refrigerant pressure switch (should be on the accumulator). you can do this simply by jumping the pins on the connector. If the A/C compressor turns on, you'll need to evacuate the system. Install the new sensor and recharge. If this doesn't work. Then you need to start checking the rest of the signal circuit for the A/C relay.. Quote
intern8tion9l Posted July 7, 2007 Author Report Posted July 7, 2007 useful info guys, thanks. i will try a couple things this weekend if i get a chance. supposed to be balls hot, and windows down only goes so far. especially in traffic Quote
RJansen658 Posted July 7, 2007 Report Posted July 7, 2007 Hmmm. My a/c system is fully charged w/134a, and blows COOLED but not cold air. I have checked the blend door, had the system evac'ed and recharged, and still it isnt cold at all. It holds a charge jusr fine, the compressor engages and runs as it should, the lines to the core up near the radiator get condensation on them, but it just blows slightly cooled air. I am lost on this one... it should be working fine.... Maybe I just need a new evaporatot, condenser, and orofice tube? If our systems even hae an orofice tube... Quote
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