Alright so i'm tired of my a/c not working in my black runner when the heat index is over 100...So far i've replaced the fuses, a/c relay, a/c amplifier and charged the compressor but it still will not kick on. I can however apply positive battery voltage to the compressor wire and she works but i dont like the idea of having 2 switches. If anyone has any ideas please help

 

hows about the low pressure switch?

you say you charged the compressor, what did your gauges read

 

There is an a/c relay under the dash, have you checked that ?.

 

also could be a blocked orifice in the evaporater under the dash.
means replacing that and regassing, check low pressure switch 1st.

 

well i figure its something electrical because i jumped the compressor from the battery and i got COLD air so i'm pretty sure the system is fine. The relay is brand new as of last week. I think now i should check the thermistor or pressure switch. During the resistance check the thermistor failed and the pressure switch was fine.

 

I had a 99 Saturn that the AC would only work when the temp was around 70 degrees. It worked fine when it did work. It turned out that the system psi was just a little low. When the tem warmed up it brought the system pressure up enough to work. Have your system psi checked and if not try the system psi switch and/or its wireing.

 

x2 replace pressure switch. let us know how it goes. tim.

 

check for voltage at your low pressure switch. it should be on the dryer/filter. most likely will have 2 wires on it. if you have power on one wire, the i would say the low pressure switch is bad. you should be able to change it without removing the freon.