So I guess that means, I should have used one of the 3.3V ground pins…like the one directly next to the signal pin I am using.
So the ground between the 3.3V and 12V is not common…I should have known that.
But you got me there. I can see the traces go straight to the chip but never put two and two together. Your comment somehow made me realize the 3.3V part. That is, if I am right about that.