Have just fitted a Witter swan neck detachable and paid for the dedicated electrics set from pfjones. Fitting was relatively straight forward and I hoped that by buying the plug in kit that the electrics would be a breeze too.

Followed all instructions provided but for some reason the brake lights on my trailer board refuse to work. The trailer board works as I have tested it on another car.

The system is presumbaly connected to the CANbus as there are only 5 wires taken from the dedicated plug into the (presumably) CAN bus unit

I haven't had the dealer set up the computer to know about the trailer yet but I'd have thought that the brake lights would work anyway,

All other lights work OK and the fog light is disbaled if I have the trailer plugged in, though the trailer board doesn't have a fog light so I don't know if that will be working.

Any idea what the problem might be ?

think it needs a software update informing the vehicle that a towbar is fitted.

It was a bent pin in the freelander socket, all works fine now.

Question is now is it necessary to get it re-programmed at the main dealer ? By which I mean is there any other benfits/safety features than turning off the rear parking sensors whan a trailer is connected ?

if it all works then leave well alone