So I'm looking for any information of additional electronics or sensors that may be involved in this ac system. I guess it would have to be some type of sensor or computer controlled system that cuts the compressor off if there is a problem.

On my compressor I have two ports for electrical connections. The one up front engages the clutch with a simple positive and negative connection. There is another in the back that I'm not sure what it does. I believe it is some type of safety shut off switch that turns the compressor off in case of some type of extreme temp somewhere that may cause damage to the ac system.

In short I'm not sure if my ac system can hold refrigerant though I am sure its empty as I've never really used it in 10 years. There is no pressure and the lines can be disconnected without any gasses escaping. No I did not release the gas into the atmosphere, my ac has never worked. The controls from the dash will not engage the clutch. Recently I've found out that this may be due to a low pressure or no refrigerant. Though the wires do not even put out 12v when the system is on. This is why I wonder if it is computer driven with some sensor somewhere. Maybe those wire leads at the back of the compressor tell the computer there is low pressure and not to supply 12v to the clutch to engage the compressor.

What do you think might happen if I put 12v to the clutch with refrigerant in the system? As long as there are no clogs, the compressor isn't seized up or making odd noises should the refrigerant then flow through the system and blow cold air despite any sensor issues?

Thanks for any info in advance. I'm looking for as much info on this ac system as possible.

1989 Firebird Formula ( original 5.0 TBI , carb but computer still hooked up )

 

there is a pressure switch on the back of the compressor and I think a high pressure cut-out switch in the liquid line. There is a low pressure switch on the accumulator. If there is not sufficient refrigerant, the compressor will cycle rapidly or not at all. These systems are independent of the computer so, make sure that your fuses and relays for the ac system are good.

 

Will do. Any idea of what that second set ( 2 ) of wires is that goes into the back side of the compressor?

 

If you jump the switch on the accumulator the ac clutch should turn on and draw in the refrigerant.