Trailer hook-up, wiring question.

Tell me how wrote: »

Why would canbus have issue with load from a trailer outlet which was put there for that reason?

Put there by who? it happens all the time with DIY scotchlok and cowboy installs.

OP may be talking about a relay to run caravan fridge, (attempt to) charge caravan battery or run.
I'm sure they will be along to tell us any minute.

Hamsterchops wrote: »

I have a towbar on my car with a 7way connection, question is where would I buy a cheap relay? It's only to tow a small trailer with a basic lighting board, so I don't want to be spending a lot. I think Halfords sell them for €40 or €50 which is too expensive (on top of the price of our tow bar), so who sells cheap basic relays?

Thanks in advance.

30-40 quid is about what you will pay for them. If your getting a towbar fitted the fitter may have a deal for lighting circuit if he’s not already fitting it ( they usually do)

Newer cars don’t take too kindly to tapping into the lighting circuit to power trailer lights an hence you need a relay unit that senses when the light is on and sends a signal to turn on the trailer lights. Might be worth checking with some of the towbar fitters, my car (BMW 5 series) needed a canbus connected system which was more expensive than the usual relay unit.

Unfortunately it’s the law to have lights on a trailer no matter how small it is so if you can get a kit for 30-50 quid then it’ll save you a lot of hassle and no doubt a fine if caught.