How to connect an electric socket for towing?

atr · Unread post by **atr** » 22 Oct 2010, 09:14

Hi
I'm a bit confused. I want to attach a towbar to my 2001 xantia. I've asked if there a need for relaies for the electrical socket or it can be connected directly parallel to the tail lamps, and I got contradictive answers. I think that an answer from people that have it installed in their car, are the best source for information.
Thanx.

jgra1 · Unread post by **jgra1** » 22 Oct 2010, 09:38

I am fairly sure on my 1999 that there are no relays, just a useful beeper for the indicator

if your using the other towing socket, for caravans, split charging etc then that would be a different matter.. but if just using the normal trailer socket I dont think you need them

John

JohnD · Unread post by **JohnD** » 22 Oct 2010, 09:44

Do you want both 12N and 12S sockets? I've wired my C5 and a previous Xantia with both sockets. I find the best way is to run a heavy cable directly from the battery via a fuse close to the battery. Then take the road lights directly from the rear light units into a Smart7 relay, and then to the socket. By law you need to have either a buzzer or a light to show when the trailer indicators are flashing.

If you're wiring for a 12S socket for battery charging and fridge, then use a self-switching combination relay. That will ensure the fridge only draws current when the engine is running.

Unread post by **RichardW** » 22 Oct 2010, 09:49

It depends on what you want to do.....

There are 2 sockets - 12N for lighting and 12S for additional services for caravans (battery charging, fridge etc).

For a 12N socket you don't need a relay (except that you need to fit a flasher repeater relay so you can hear if the trailer indicators are working) - this is all part of a standard wiring kit. You can just plice into the wiring loom (scotchlocks, or solder / heatshrink if you're a perfectionist!). The only slightly difficult part on a Xantia is picking up the fog light wiring - although I am led to believe there is a wire somewhere with a blank plug on that might be easier to access than doing as we did and taking the C pillar trim off. There is also some people that fit a relay to the fogs, so that when you are towing a large trailer (read caravan!) the fogs on the car don't come on and reflect on the trailer.

For a 12S socket you should fit a split charge relay so that the charging and fridge pins are only live when the engine is running, otherwise you risk flattening the car battery if you leave the 'van plugged in.

Towsure I think has a pretty good explanation on their website.

Unread post by **Old-Guy** » 22 Oct 2010, 12:44

Richard has covered it comprehensively - except to say that judging from the electrics fitted to my 96 Estate by the original dealership, it's necessary to take the O/S indicator from that side, the rest of the lights are connected on the N/S. It should be possible to connect up by doing no more than getting at the back of each rear light clusters as you would do for changing a bulb.

You may have to drill a hole in the floor to pass the cable through. Paint the bare edge and use a grommet that fits or a big blob of silicon sealer otherwise you'll get a wet boot and a big rusty hole in a year or two!

atr · Unread post by **atr** » 22 Oct 2010, 14:15

Thank you all for your answers. my only intention is to tow a small luggage trailer, so there are no complications to wire the socket up. I will connect the wires to the rear lights and thats that. Old Guy - I think that citroen made some progress, since in my xantia there is a hole at the center of the boot which seems that was made just for this.

Unread post by **RichardW** » 22 Oct 2010, 15:50

In theory, you should take the side lights from separate sides of the car too - so that if you have the facility to park at night with one side on (as VW and maybe Vauxhall can do) the trailer follows suit. I suspect in reality most fitters these days connect them together! Depending on the how the car's wired, you might be able to pick up the NS indicator on the OS.

atr · Unread post by **atr** » 22 Oct 2010, 16:22

Sorry for my ignorance, but what are the NS indicator and OS standing for?
Thanx.

Chris570 · Unread post by **Chris570** » 22 Oct 2010, 16:29

NearSide and OffSide (relative to the kerb, so on a Right Hand Drive car N/S is the passengers side)

wheeler · Unread post by **wheeler** » 23 Oct 2010, 10:41

RichardW wrote:In theory, you should take the side lights from separate sides of the car too - so that if you have the facility to park at night with one side on (as VW and maybe Vauxhall can do) the trailer follows suit.

I always assumed that you wire both tail lights independently as both tail lights are usually fused seperatly & joining them together would mean you would loose both tail lights if the fuse were to blow ??