I have an '01 SE Xterra 4X4. I have the mirror with the temp readout and compass. There are two buttons on the mirror, the one on the pass side goes from celcius to farenhight. The one on the drivers side of the mirror just turns a little green dot on or off right beside the button. What the crap is that? It's not in my owners manual and i can't notice any difference with the green dot on or off. I am going insane!