Looking at fitting a tow bar on our 307 hatchback so we can use a trailer for camping trips etc. Now there are loads of kits about for under £100 and i reckon i can cope with fitting……however i have a bit of a query most kits come with electrics but they say may need a 7 pin relay fitting for vehicle electrics. Anyone know or have experience of what/why this is?

2006 307HDi

Just had one fitted to my 307SW last week. Am as handy as the next guy and was all for getting a kit. Then I started reading up on the electrics.

Peugeots after 2004 have a weird centralised multiplex system which has feedback sensors and the like which in a nut shell means you cant just tap in to existing connectors like the old days.

I think you can get specific electric kits for about another fifty quid, but add to that some horror stories about 1k bills to replace the whole electrics and I decided to stump up the 185 the local towbar place was charging all in. Took them about an hour.

its a relay that stops you doing the above generally available on ebay 20 ish
http://cgi.ebay.co.uk/Universal-7-Way-Smart-Bypass-Relay-/260767965291?_trksid=p4340.m263&_trkparms=algo%3DDLSL%252BSIC%26its%3DI%26itu%3DUCI%252BIA%252BUA%252BFICS%252BUFI%252BDDSIC%26otn%3D8%26pmod%3D280630206310%252B280630206310%26po%3D%26ps%3D63%26clkid%3D8703564267588956777

The relay provides its own power direct from the car battery rather than via the existing wiring loom.

You still connect into the wiring, but the relay is just using this to sense which lights are operating so it can then provide power to the trailer lights, rather than the bulbs drawing power through the loom.

If you connect directly, some lights won’t work, you may get bulb failure warnings on the dash. Or you may cook the whole lot!