I just noticed that my 2012 Edge M18 has an exhaust fan under the kitchen sink.. it's kind of hidden behind stuff so I never saw it before. It has an electrical wire connection, but I have no idea how to actually turn it on. I don't see a button anywhere.. does it turn on automatically when I turn on something else? I figured that it was there because of Grey water tank fumes that can come up.. but no idea how it is actuated.