Long story short - I smashed up my 7-pin plug on a BuzzRack platform bike rack and stupidly stripped the wires from the broken plug without noting down how they were wired.
I now have a new 7pin plug but I'm not sure how to wire it up as most diagrams I see have at least 6 wires to connect.
Does anyone know how to wire a 7pin plug with just 5 wires?
I know, I know, I'm an idiot....
Just google for n socket/plug wiring diagram.
You need to identify the pins as some diagrams will view it from the back of the plug, and some from the front.
The missing wires will probably be positive and negative for caravan battery charging/fridge
thanks spooky - I have all wires except black and blue. I'll look later today
Sounds to me as if you need to use a standard wiring diagram and connect your five wires for
Neutral = white = poition 3
Brake = red = 6
LH indicator = yellow = 1
RH indicator = green = 4
Tail= black or brown = 5 or 7
Normally the 2 tail lights have a separate wire for each side but this is not necessary so you can stick your tail wire in either of the 2 positions on the plug. I guess your tail board is also missing a fog light, which would be the 7th wire on a normal trailer plug (blue in position 2).
http://www.westerntowing.co.uk/acatalog/Trailer_wiring_diagram.html
Blue is fog light so I assume your rack doesn't have one - so can be ignored.
Black is LH side light so I'm guessing your rack has a single wire for both tail lights - brown.
So I would suggest using a 7 pin wiring diagram and simply ignore blue and black.
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OK just read your 2nd post. So nothing in position 2 (Fog), and the brown wire can go in position 5 or 7, it won't matter.
The spares will be fog and possibly reverse? [edit] [i]beaten to it, and not quite right[/i] [/edit]
There are rules about what lights are required based on the width of the trailer, as a minimum (i.e. what most bike racks have*) it'll be indicators (x2), tail, bake and the neutral wire.
*not quite sure why, as 'trailers' go bike racks are quite wide. Probably get away with it as the rack is considerably narrower and the bikes overhang, dubious but cheaper than a full light board.
Managed to strip the wires out of the plug on my trailer on Sunday by not unplugging before unhitching.
After 2 failed attempts at rewiring I've just realised my mistake - I was looking at the wiring diagram and applying it to the back of the plug not the front.
Still only lost an hour whilst I waited for the RAC to rig up a couple of temp sidelights to get me back home 🙂
DOH!
Thanks everyone