Kitchenaid cooktop - combo burner only works as big

Thanks. How could it be the burner as both of the elements of the burner do work (though not at the right time)? Seems as though it’s either a stuck switch contact as noted in the video link or perhaps incorrect wiring (seems unlikely).

I can’t easily diagnose as it’s at a vacation home that’s a couple hours away, thus I’d like to narrow it down as much as possible and order parts before I go there next.