One day the wife bumped it.
Inertia Switch, happens a lot, sometimes it doesn't even have to be a hard bump either.
In the old days if you knew about this it could be reset by pressing a button down, nowadays it has to go on Dealer Level Diagnostic Machine and be reset in several of the ECU's
Applies to lots of Marques, this is the shit I do for a living these days, (vehicle programming resetting etc) as well as regular stuff, as I have the eqpt and knowledge.