My spindle crashed and then wouldn't turn back on after the crash. (I suspect the crash was due to ESD problems -- where it crashed the dust collection hose brushed up against one of the unshielded end stops).
I found the problem on the KStep board (transistor Q6), which I replaced with a regular 3904 transistor.
At any rate, I made a video and figured I'd share it here in case anyone else runs into this.
https://www.youtube.com/watch?v=MPcCB0yV4Nc
KStep Debug and Repair
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