I checked ground and it was fine, the power may be a problem as I don't have a specific fuse I plug into because so far all of them haven't worked even the circuit breakers. The wire seems to be a good gauge but then again Im not really sure.

When i fixed the splice mid wire it stopped smoking there and moved to the switch. Earlier I got the windows to move, this Is a universal harness on a car not meant to have power windows, and they never did before. Once they moved the wires got very hot and I shut the car off.

What could be the cause of this

 

Bad ground somewhere

 

Yep, not likely the ground . If you have a properly sized circuit breaker in there (pretty sure the window circuit uses a 30A breaker) , and your using an aftermarket "universal" harness, and the window motors will in fact move while the wire is roasting , , , , , then the wire is too small to supply enough current to the window motor

 

Im actually thinking of changing ground and cleaning the surface for it just to be safe

 

ok thank you, like i said I plan to move ground to its proper location and clean it up as every ground is a bit rusted but i do have an old wiring harness the previous owner gave me that I didn't trust entirely so I can use the wire from that