Look in 'Electrical Circuit Diagrams' under 'Trailer Socket' heading.
Printable View
Look in 'Electrical Circuit Diagrams' under 'Trailer Socket' heading.
Hi Mudguard,
I agree with sniegy's post, in the 6 years I've been building trailers ranging from small box trailers to trailers for large boats and vehicle recovery, I've always wired up to this method. Haven't had anyone complain yet either so it seems to be pretty standard.
As for your problem, the easyest option would be to get your mate with the caravan to plug his vehicle into your trailer and try the lights then; If the trailer lights work fine than the problem lies with the wiring in your vehicle. If this hasn't fixed the problem than there is a problem with the wiring on your trailer.
Possible things to check would be the bulbs again, even though they look fine this isn't to say that they are, for the price of some new bulbs it would be considered to be a quick, cheap fix. If it doesn't fix the problem than at least you can deffinately rule them out. Check the connection of the wiring in the plug, make sure the wires aren't loose. Check the quality of the contact between the bulbs and the metal contacts that they attatch to in the lights, ensure these are clean from dirt or rust. Check the quality of the earth wire and where it earths on the trailer. If all of these seem to be fine than it appears there would be a break in the wiring. You'll need to find where the wire is damaged and repair it by soldering them back together and insulating the soldered joint or crimping them together with insulated crimps. If the damaged section can't be found than you may need to replace the wiring.
Hopefully this helps you out & I have explained things clearly enough.
Best of luck.