Ymin homing, but not

Mostly Printed CNC - MPCNC Troubleshooting
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I’m not sure if this is a brand new issue or not, but I feel I’ve been running fine for the most part. I had not noticed this issue till just now and only because it acted up as described below. It may have been this way all along, but I am not sure.

When I home the machine, the X axis goes to the endstops fine, i.e., moves to contact the switches, moves out and then back slower to hit switches again. All good. The Y axis however, moves to the switches, then back out, but the return does not seem to be making contact with the Ymin switch the second time. M119 shows it not triggered. The other three are. Now just prior to this, I experienced an issue with the Y1 motor not moving at all when I went to home. Thus causing a big torque across the machine as Y2 would be trying, but skipping. After hitting e-stop and cycling the power to everything, the Y1 motor seems to be responding to move commands correctly but on home it is definitely not sitting on the switch like the other three.

Any thoughts on all this? bad motor? finicky switch? main board going?

I’m running on a Rambo 1.4 w/ dual end stop firmware.

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Did you find and resolve the issue with the Y1 not moving? If it is an intermittent connection, either open circuit or short circuit, then it could still be occurring and presenting as a different symptom. For homing, the second touch will only try a certain distance I think, after which it gives up even if the switch is not triggered.

Try moving Y back and forth and see if you still have a motor problem. If so, that’s very likely to be the cause of the other problem.

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Mystery solved. The Ymin switch died. m119 was showing always triggered when I cam back to it this evening, so I guess it thought it was already home. It must be intermittently bad, because last night it was showing as not triggered when it should have been, go figure.

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