Why don't my backup lights work?

What is your question?

No backup lights on my 2002 Ford E250 V8 5.4 fuse is fine. Bulbs are new. What else could in be? I cut a wire several years ago, red and black and one end that was hanging under dash loose, has a phone jack looking thing. I'm sure they worked even after I cut that wire. This was a work van before I bought it and it had all kinds of work related stuff in it. Like and extra battery under side door and that beeping alarm when backing up. Does this wire sound like anything that would affect the backup lights? Won't pass inspection without those lights working and can't afford to bring it somewhere, so I'm trying to do this on my own. I am a 57 year old woman in disability and don't know much about cars

How long has your 2002 Ford E-250 Econoline had this problem?

A year or so