Having some issues with a customers 1991 NA car and figured I'd explore options here. I'll try to give as much info as to what me and previous mechanic have done.
Basically his AC went out one day and he takes it to a shop and they say hes low on freon and has a bad compressor. So he has them put a new compressor and dryer on and add freon. That does not seem to do the trick and they tell him he needs the auto ac amp. This is where I come in. He brings it to me and I proceed to get a amp from a 92 parts car I have. I try it as well as the one from my 92 slicktop. All cars also had the auto ac but I do not know if ac worked in any of these cars. That did nothing. I went through the ac diagnostics and discovered a short in the ambient sensor and a open circuit in the sensor in the headliner. I replaced and plugged in the 2 sensors and now I get all good in diagnostics as far as the sensors go. I can turn on the compressor in diagnostic mode step 2. I can also turn the compressor on if I bypass the pressure switch plug and ground the jumper like with a test light. I get power at the ac relay. I also get all the correct power and grounds in the ac amp tests. I have switched out the switch pods 4 times with no success. The only 91 above ecu I have is out of my 92 NA which again never had ac hooked up. It did not help. I have checked continuity from ecu pin 9 thru the orange wire all the way to pressure switch and then checked LG/B wire coming from switch to the ac relay. All good. It still seems to me that one of the 2 computers in this chain are not telling ac relay to turn on. Yes I checked the green wire running to the compressor. Any help would be appreciated!!
Follow Ups
AC compressor wont kick on unless in diagnostic mode - DracoZ16:39:17 08/01/14
