@mce15 said in Fried U3 chip on board out of warrenty:
I just checked the BL touch wiring, and im pretty sure i inverted 5V and GND
That's a common way to blow up the regulator.
You're not the first nor likely the last one to do this.
BUT, you got it working again!!! Nice job staying with it until you both found the cause of the problem and found a way around it.