Runaway trim motor almost took out my knee last week

I was doing a preflight check on a King Air and the horizontal trim started moving on its own while my hand was near the jackscrew. It only moved maybe two inches before I hit the kill switch, but that was enough to make me jump back and bang my shoulder on the panel frame. Turns out the trim motor limit switch had a cracked solder joint that let it bypass the cutoff. I pulled the whole actuator apart and found the issue at the board level, not the switch itself. Took me three hours to tediously reflow every joint and bench test it through the full travel range. Anyone else had a trim servo go rogue on the ground or in the air? I always assumed those limit switches were bulletproof until now.

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