mike1911 on the light base there is a small sliding switch that controls on/off. As for the FW tank drain, like Boso said, in the second from the back compartment on the right side ( passenger) there is a black panel ( held closed by two silver thumb tabs) behind this is the water filter housing,the water pump,and the drain valve.Not to sound mean, but did your dealer not show you this?If he didn't I'm sure he didn't show you were the slide control box is either.If he didn't, ask and we are all here to help you. Congrats on the new MH, I have the same one just a year older