1988 Camaro IROC - Installed this system: https://www.originalair.com/88-92-ca...RoCqKMQAvD_BwE

My air conditioning was ripped out of the car from the previous owner, I'm assuming he did this when he installed the FAST engine management system. In the directions it tells me to cut the wire harness going to the old compressor, connect the green wire to the new compressor and abandon the black wire. Mine has a switch behind the old compressor in which the directions told me to splice those green wires together.

Finishing up my installation and I am wondering what signal I should be receiving from that green wire when I try to engage my AC because as of now it seems to do nothing. My blower engages, but there doesn't seem to be a signal sent to the compressor. Just wanting to make sure my wiring is all in order before I take it in to get charged. Does this need pressure in the system to send a signal to that wire?

Question: Do those wires really just get put together, and how would I see if my compressor is getting power?

 

Nick, I can not answer for the "original air" system because I've never worked on it, but I can tell you for certain that the factory system won't send power to the compressor clutch if there is not enough refrigerant. I'd be inclined to believe that the aftermarket system also has some means of protecting the compressor from running dry, a pressure switch of some sort plumbed into it .

 

Yes, the aftermarket System in the Hyper-Link, does mention a "Pressure Cycling Switch".

 

Do you have an aftermarket ECU then? Also is the harness different. The factory system had a signal going to the computer when the a/c head was turned on. this would go through the whole a/c wiring (blowers, switches, etc.) to the compressor. If everything is still factory for your wiring, then yes, do exactly as the directions say. On the old compressor you had a pressure switch below the green and black wire (with diode) going to the compressor. that needs wired together to complete the circuit. The new compressor has an internal switch. If you do not have original wiring, you will need to figure out a way for that signal to go to your new ECU also, to tell it to turn on and off according to your logic you program the new computer with (WOT, idle bump, etc). Yes, it will also need to be in working order to function (charged). If you need ideas on the wiring, check out "what ever happened to Quiktrip's" car thread. He does have some options there, although it is a Holley ECU that he is using and shows the logic that he set up with it. I am not familiar with the Fast system (if it has the same capability or not), but the wiring of the A/C should/can be the same if you need to go that route.