Tow bar electrics

[spiff]

Good evening Gentleman,

I have had a good read through the forum regarding trailer lights wiring, but could not find an answer to my question.

C5 2003 petrol estate, the car is fitted with a 7 pin in line socket, the trailer we have just obtained has the more normal round connector.

I have sorted the mounting of the new socket and the colour coding.

It is for a small garden type trailer not a caravan.

On removing the inline socket it was apparent that the cable at least towards the ends is corroded inside, the earth lead was so brittle outside and in that it snapped off quite short .

I could try soldering a length on, but as all the leads are in the same shape it would be best to replace the cable back to where it connects somewhere on the left hand rear.

I do not know if the cable is a properly fitted, one or has been installed DIY.

Is it likely that I could get at the spot it is connected into the wiring harness, by taking the LH rear light covers off then pulling the fittings out ?

Or will the panelling all have to come out of the boot area ?

My thoughts are that if it was DIY they would have tapped in just behing the lights. ?

The wires are thin more so than they look in the image, not all the pins on the original socket were connected, though the wires were all there cut short..

God Bless Spiff

[spiff]

Nothing heard so for the benefit of other searchers, two bolts to remove the rear light pods under pop in covers next to the tail lift.

The wiring to the lights is a lot thinner than I expected, it was also on the stiff side so I decided to use the original trailer socket wiring.

I soldered an extension on to the broken lead, it took a lot of scrapping.

Covered the join with heat shrink also the ends of the un-used wires.

Soldered some metal surround things to the end of the wires, so that they would make a better connection with the socket screws.

It all worked fine, one of the cables had faded from brown to a pinkie colour, something to watch out for, that was the one that broke..

Gods Bless Spiff

[MattBLancs]

Not seen one of those flat connectors before (only round 7 pin and the newer 13 pin trailer sockets/plugs) interesting, thanks for sharing.

I've recommissioned a trailer (that had lived in a field for who knows how long - long enough for the wooden floor to have disappeared anyway!) Trailer wiring and towbar wiring can both use the same 7 core cabling.

This old trailer's wiring was hard as you described. Another later trailer board had been added and the wiring on this at both light units and towbar socket end was tarnished. So stripped it back to expose "fresh copper" - still tarnished. And again, and again. Quite surprised that the copper was oxidisation for a good length along the (appeared undamaged) insulation.

Ended up chucking that wiring and starting with fresh new 7 core cable. Can buy it online and think better car shops will carry it?

Matt

[spiff]

Capillary action maybe.

I have found it on old radios that I have been renovating, probably been in a garage or shed for years before I found them.

Also on insulated wire that has been outside in use as an aerial, it travels many meters : )

This is not intended as a how to wire yours, just to show what we had to sort out, I was a radio engineer but it tried my understanding LOL

Picture attached a bit rough shows the old car inline socket wiring and our trailers wiring, all a bit confusing : )

We metered the wires while turning on side lights, indicators and brake lights and wired the new socket with that information.

There is loads online about the wiring, but watch out I came across an eBay listing with it wired backwards : )

On the old car inline socket only one rear light feed was used, we changed this on the new car socket ?

The wiring on the trailer itself was fine and a lot thicker, the trailer was free on FreeCycle, which is always good.

God Bless Spiff

[Rp0thejester]

Wow, that's alot of work. I definitely wouldn't have the patience to do that. I would of just bought an adapter.