wired them up and don't come on. took the pos of each wire and connected them together then spliced into the rev wire on the 7pin plug. connected both neg wires of the lights together then grounded to frame, sanded down to bare metal. any ideas??? took everything off then put the power and negative to a older 12v car battery and they both come on

 

I'm no electrician but I tied mine into the wires for my factory reverse lights and they work like a champ. Maybe see if that works for you.

 

Did you install the trailer fuses and relays into the engine compartment box?

When I installed mine I tied them into the trailer ground as well.