[zoner]

Does the light illuminate (off position) but the ASC+T is still functional or does the light not illuminate regardless of switch position? If it's the latter, I'd assume it's a faulty switch. Switch failure is not a common problem that I'm aware of but like any switch, it does have a lifespan and being that the newest models of our cars are closing in on twenty years old, it's not unexpected for things like that to start going out.