Security Set

Can someone please help me,I have a 1999 Town&Country it stalled in my drive way could not get it to start,I had a so called mechanic come over and he got underneath the van with a piece of grey wire and some how started it I ask him what he did he would not tell me he put a starter switch on and told me I would not get stalled the security system went off it was fine for 2 wks now i am back to square one,my security set is on it won't start won't turn over at all,it will turn over when I push in on the starter switch but won't start.can someone please tell me what he did or how it can be fixed.