UM2+ Error x or y switch broken

[Bzjammer 0]

I received an error on the UM2+ that says the x or y switch is broken. I went through some trouble shooting with fbrc8 and determined the end stops are triggering properly. That was figured out on wednesday and that was the last I have heard from them. Does anyone know any remedies or fixes for this?

[IRobertI 429]

Have you checked the pulleys? If one of the pulleys is loose so that the head isn't travelling as far as the firmware expects, it will also trigger this error.