towbar electrics

hi chaps, i know this has benn asked many times before, i have done a search but cant find what im looking for.
i fitted a towbar to my v8, the electrics had a moulded plug which i simply plugged in, great, every thing works except for the brake lights.
now not being good with electrics, but will have a go, can anyone point me in the right direction as where to look,
thanx in anticipation

I would look at the brake wiring.

You should not have a problem if you have used a genuine wiring loom as that just plugs into an existing socket behind the o/s rear load space/boot panel, other than that go the where ever the traile socket witing is terminated to the vehicle wiring and start testing circuits.

every thing works except the brake lights..... does that mean the vehicle brake lights no longer work or just the trailer brake lights?

if its just the trailer brake lights id suspect the trailer itself first off... can you try another trailer or light board on yours and try your trailer on another vehicle.... then youll know whether its your trailer or your vehicle thats got the problem

corrosion / dirt on the pins in the towball socket and plug are often the problem

there are people that think that as long as the rhs indicater works anything else is a bonus...