Wiring for trailer coupling; help please!

[horrid1]

I am fitting a towbar on my XM but am wondering if the old standard way of hooking up the lights will interfere with the ecu. Is it necessary to fit relays? I was quoted $NZ1200 to make and fit a bar and lights ( with relays) to a car which cost $NZ1500! So I bought another car with a towbar for $NZ800, but it has no wiring connections so I have to find out for myself!!
I will make a bar myself (using one as a pattern), and will have to wire up the two cars. Some advice will be appreciated. Thanks, Ernie.

[JohnD]

I'm just in the process of fitting a bar and electrics to my C5 estate and I've met with the same dilemma - whether to fit relays or not. Some say not necessary, others that it is. I've decided to play safe and fit them. Citroen also do a plug-in kit, but at a big expense, so I'm going to use blue connectors on the back of the bulbs. In the UK, making and fitting a towbar is illegal. Since 1998 every towbar now has to conform to strict EU approval, hence the cost of a bar has doubled in price.

[cornishbx16v]

i got my local towbar man to fit my electrics and he didnt use any relays on the bx???? took him abut 5 minutes i think!

[JohnD]

[quote="cornishbx16v"]ihe didnt use any relays on the bx???? quote]

It's multiplexing and bulb failure detection that needs relays. My previous '98 Xantia didn't need them either. For the same reason, I don't think Ernie's XM will need them.

[Peter.N.]

If its of any help. I have a genuine Citroen towbar for my '96 XM estate which I havn't yet fitted but it has a loom with plugs on it that fit into the existing lights. No relays.

[NiSk]

Not even my late '98 XM Break has relays fitted to the towbar electrics.

//NiSk

[bxbodger]

, making and fitting a towbar is illegal. Since 1998 every towbar now has to conform to strict EU approval

Its still not illegal to FIT your own towbar, its just that it has to be an EU type approved one if the car is post 1998.
If your car is pre 98 you can still fit non approved bars, or make your own if you want to!!

[andmcit]

FWIW incidentally...

the XM's tail light plug-in pcb connections have a second parallel plug available where you can run another [spliced from a scrap yard donor] multi plug out of to connect the tow bar electrics/wiring. You may already know this, but I was well chuffed when I discovered it!!

- no nasty splicing of looms and awkward access etc...

Andrew

[horrid1]

8) I'm overwhelmed!!
Thanks for the prompt replies. I will hook them up without relays for a start, it will be easy enough to add them later if necessary. I have a spare fuse board and relays out of a BX which I may try and adapt. I didn't mention that both cars are series 1 V6's; 1991 and 1993 models.
We are allowed to build and fit our own bars on private vehicles, I have seen some pretty dodgy looking ones at times.

Thanks again, Ernie

[JohnD]

Talking of homemade towbars. Here's one a Frenchman made earlier!

[Gregg1100]

HI,
Found this in my Favs bin,

http://www.rydertowing.co.uk/trailer_to ... wiring.htm
Hope it is of help,
Greg