None - Trailer Lighting

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Mon 24 Jun 2013 20:54
None - Trailer Lighting - kerbed enthusiasm

Hi all. I'm seeking some advice before shredding my wiring! I created a lighting board for a trailer using plyboard. The tail, brake and indicators all work without a problem. The foglight doesn't work at all and when I switch it on it takes power off the number plate light. I've chained the earth wire around the lights. In sequence it goes to the indicators, the brake/tail lights, foglight and then the numberplate light. So, what's going on? Too many connections to the earth wire perhaps? Incidentally, turning on the foglight also blew the car's foglight fuse; I'm pretty relieved that that's all it did!

Thanks in advance!

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Mon 24 Jun 2013 21:01
None - Trailer Lighting - Cyd
sounds like you've effectively wired the lights in series rather than parallel. wire all the negatives to a common point and then connect that to vehicle negative.
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Mon 24 Jun 2013 21:08
None - Trailer Lighting - kerbed enthusiasm

Thank you. So plyboard off the trailer, rip out the mastic that has been used to protect the wires and start again! Thought I might be able to get away with a series circuit - obviously not!

Thanks for the advice.

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Mon 24 Jun 2013 21:27
None - Trailer Lighting - Collos25

Is your vehicle canbus if so its slightly different you will need a relay if not carry on,wiring diagrams available on the internet.

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Mon 24 Jun 2013 22:07
None - Trailer Lighting - elekie&a/c doctor

Are you using regular 7 core cable,or something more homemade?If you have wired the circuits in series,nothing would work correctly

Edited by elekie&a/c doctor on 24/06/2013 at 22:08

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Mon 24 Jun 2013 22:43
None - Trailer Lighting - kerbed enthusiasm

No, fortunately not canbus and yes :-[ earth wiring was in series. In my defence, I'd taken this from an internet source and made an assumption that as it was only the earth thath was wired in series then it would be fine. Patently not!. For the record, yes, it's standard 7 core cable. Easily rectified with a bit of soldering and probably a chocolate block connector though I don't like to use these.

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