Originally Posted by
Takwis
MCAS is powered through autopilot trim. Some time ago, in a thread far away, someone posted a wiring diagram showing MCAS trim running through the STAB TRIM OVRD relay, thereby bypassing the control column cutout switches.
I think that may have first appeared as post #737
https://www.pprune.org/rumours-news/621879-max-s-return-delayed-faa-reevaluation-737-safety-procedures.html#post10504031
Other, but not all, wiring diagrams on #750, #780 & #947