So, after investigating the reason behind my compressor not kicking in, checking all the relays, fuses, and wires, etc., I still can't seem to get it to come on when I want to.

Would it hurt it at all to run a wire from the battery to the compressor clutch itself, and wire it up to a toggle switch? I know for a fact that doing that works, just I don't know if I could do that and run it for longer than three seconds.

Theoretically, it should work. The wire will kick the clutch in, and thus turn the inside of the compressor like it normally does. But the high/low pressure cycling switches come into play. What are their actual purpose?

 

the purpose is to maintain the system in the right pressure. There is a fail safe vent valve in the compressor that will Vent out all your freon if compressor clutch stuck ON for what ever reason, or the Cycling switch failed.
The Hi side switch is to prevent your A/C blowing up, the Lo side switch is to prevent your evaporator becoming a block of Ice.
so, jumping the compressor more than 3 second is asking for trouble. You just have to get it diagnose. does the compressor comes ON at all? what is your exact problem, and what did you check?

 

It doesn't cycle on at all. The only way to get it to work is to jump it like previously described.

Thus far, I've changed the control switch, fuse, relay, and high pressure cycling switch.

 

I also replaced the control resistor, and it still won't kick in.

 

I'm not 100% sure on Neon's systems but there is a low pressure switch that is used to protect the compressor. Have you jumped over that switch with a paperclip yet or not?

 

The mechanic at a shop said he did, but that was with the old compressor. I'm getting it looked at tonight to see what can be done.

What if shorting the low pressure works? What if it doesn't? What is the entire procedure for diagnosing? What should I check after I check the low pressure sensor? The high?

 

I assume you charged the system.
It could be your low side switch.
Another thing to check is ambient temp sensor. ask you mechanic to hook up a scanner, and look at the Ambient temp data. If the Ambient temp is reading like -40 F, the A/C will not turn on because it thinks it is too cold outside.
if it is a wiring issue, there is not much I can say without writing an essay... there are pages of diagnosing instruction you can read up in repair manuals, your mechanic should have one(at least I hope you are going to a mechanic that has one).

 

I'll keep that in mind. I will have the low pressure and high pressure changed seeing as the system has to be discharged to do them. Might as well get them both out of the way.

 

Did you get it looked at or no?

 

Not yet. But I'm pretty sure it's the high pressure switch.