I have to replace the rocker switch on my bunn b10's warmer plate it is a three terminal switch and I have the hot to feed the switch then I have the hot to feed the warmer, with a nuteral. The switch is marked 1, 2, 3, how are the conections made to what terimnal?

I need a wiring diagram for a Bunn GRX-B coffee maker. I have a problem with the upper switch that tights when on... Can you help?----Ray.