My Cheapo Chineese 3020t mini CNC Build (more like improvements) leanring all the way

[Zeeflyboy]

ah I get you...

I would double check your soldering on the Y-axis input then and also double check however that inputs/outputs board connects to the motion controller is plugged in fully and all required wires are present and correct.

If you have a multimeter you can check for any shorts on the input side, continuity between any of the pins would show that you have a short in there which would present a permanently closed circuit, thus any opening of the circuit by the switch wouldn't have an effect, giving the result you are getting there. Worth a check. You can also check that you have continuity between the board and the motion controller on that line.

As an aside, while nice to have, limit switches certainly aren't a necessity on a machine this small with weak motors like that - it won't have the power to damage itself and you can just start it up in one corner and set soft limits if you like. My first machine never had any limit switches at all, my second machine only had one set for "home" and soft limits for the end stops. Nothing to stop you from using it "as is" while you figure out your limit switch issues.