End stop shows triggered even when unplugged at board

I just got finished assembling my Primo and flashed the Rambo 1.4 to the latest firmware (Dual All the motors are moving in the correct direction. Now I’m testing the end stops. 3 of the four stops appear to be working correctly. Unfortunately the Y2 end stop showed triggered even when not touching the stop. I confirmed the connections at the switch and at the board. I even unplugged the switch from board and it still shows triggered.
I have rebooted the system twice with no change.
Any thoughts?

Maybe upload a picture of your wiring of the board and the endstops so we can take a quick look. Instead of asking you a ton of questions.

It should show triggered even when unplugged. It will show open when the circuit from ground to signal is closed.

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Expanding a bit on Jeff’s answer, the V1 maintained Marlin firmware expects the endstop switches to be wired normally closed (shorted) and will read “triggered” when they are open. This configuration means that if a wire is knocked loose and you attempt to home the machine, the stepper won’t move. If the firmware was set up for normally open switches and a wire was knocked loose, then the machine would attempt to drive itself beyond the endstops.

If you are seeing “triggerd” when your endstop is plugged in, that indicates you have a wiring or switch issue where the circuit is not being completed.

When all the other switches touch the end stops the state changes from Open to
Triggered. Y2 stays triggered no matter what I do.
So I may have 2 issues if they are supposed to change from triggered to Open at the end stops. Still does not explain Y2. First picture is Rambo. 2nd is Y1 and 3rd is Y2.

If you are careful not to touch the (+) pin, you can jumper between the (-) and (s) pins and M119 will show open.

I know you don’t think it is a wiring issue, but I still think the most likely is a wiring issue on the switch.

A broken wire somewhere would make the switch appear to be triggered all the time.


Ok. This makes sense. Thanks

OK. Understand better now. Basically from here I need to check continuity in the switch and then the wires.