So traced the wire from the switch and it goes to connector CN8 (its the green wire with the purple stripe). Might take the board off later and see where it goes from there.

Just above the connector I noticed a missing transistor at Q48. Crashramp when you look at your pin would you mind confirming if there should be a transistor there and if so what type? From the look of the board one has been removed. I've attached a picture of the location