After cleaning some filament from a bad print off my print head I can’t get the bed to line up with the head to clean or level. The bed moves all the way to the front of the unit and stays there, just a little too far forward so the head misses the washers completely and goes down until it starts to grind. In Cura I can’t home the bed or move it in either direction, it just says the endstop has been reached. I hope I didn’t somehow fry the control board when I was cleaning. I had heated the unit up but turned it off before rooting around with the forceps. How can I test to see what I need to replace on the unit? Thanks!
Move the bed to the center of the Y axis travel. Move the print head to the center of the X travel and run a M119 command. Post a screenshot here once you do that.
They should all be open or all be closed (I can’t remember if the switch is open or closed if it’s not touching anything) but either way, they should all be the same on the X and Y axis. If they’re not, you probably have a broken wire, bad switch, or a bad connection. At that point you need to take a continuity checker and work your way through that switch to find the issue.
Of course if you’re within your 1 year warranty window, definitely take advantage of that instead.
Just a follow-up for anyone experiencing the same. Replaced the RAMBO board and end-stops began working again.
I blew up the exact same Y sensor while doing maintenance on the nozzle (and fixed it by replacing the RAMBo). I think the heater resistor insulation together with the thermistor hold plate is a bad design choice of AO. I hate to repeat myself, but nevertheless feel obliged to mention my solution.
I got rid of the lower part of the thermistor hold plate and made sure the heater resistor leads are completely isolated from the hot-end by covering the bare leads in exhaust repair cement.
And yeah, I know general advice is to shut down the printer on hot-end maintenance and never touch it with conductive brushes. It’s just too easy to short the heater resistor wires IMHO.