So I had my A/C diagnosed, and he was really no help at all. He just said "well, it might be a, b, c, or q, or it might be your computer". Irritating as hell. Anyway, would a bad computer cause it? The compressor, fuses, relays, all work, but still no A/C. So I'm thinking it's a wiring problem or I have a faulty radiator relay that just doesn't realy the a/c part of the deal.

If so, would it have to be flashed/programmed? Can I just get one from a junkyard from a 2000 mtx Neon and swap it in?

Also, there are no codes other than "IAT voltage high" which has been fixed.

 

I don't know how common it is for the car's computer (ECU) to cause a problem but I know it it's a very reliable part in your car. Only if the people who programmed it, they wrote error codes. But not very likely, because I drive a 2005 Dodge neon myself, and I never had/has a problem with it.

For engine tuners, they can reprogram the ECU to make the car runs richer, ...
But I don't think you can reprogram the ECU for the A/C only because there are no software/flashed like that available in the market. You would have to buy a new ECU.

 

There are no radiator relays. If you mean the radiator fan relays then yes, one or both of those fans need to turn on when the A/C is on.

I remember you from another thread. You still have the same problem with your A/C.
You should take your car to another shop.

 

If I knew how to read a wiring diagram any better I would have already had it fixed. The problem is that power isn't getting to the A/C wire in my control switch, and thus nothing is getting sent to the compressor.

And yes, I was talking about the radiator fan relay.

 

If I had the diagram in front of me I would probably be more useful.

The BEST advice I can give you is find the last spot on the circuit were voltage (power) is present and then find what component or wire voltage was lost and that will usually be your problem.

So if you have no power to your switch go to the next thing up the line and see if voltage is present there.

 

I don't even know which direction it runs. Obviously from the battery to the next thing, but like I said. I have no idea how to read a wiring diagram this complex. I haven't needed to since high school.

 

Upon further reading in the wiring diagram, there is a "Diode 1" that runs between the compressor clutch and radiator fan. What/where would this be? It's not any of the fuses or relays...