What operares the selenoid on the starter?

I have a 1989 snapper riding mower model 3312x6s that is powered by a honda 340gxv engine. Snapper lawnmower is equipped with a selenoid under the seat. When I turn the key on to start the engine the selenoidunder the seat operates and applys 12v tothe selenoid on the starter of the honda engine. The starter will not engage. there is a spade punching on the starter with no wire attached. Is there supposed to be a wire there? I have lots of inf. on the snapper and on the honda engine. I have no inf.where honda and snapper communicate. HELP!