Towbar Wiring

[888dee]

so first off, anyone who reckons modern cars aren't well engineered have never fitted a tow bar to an A4!!

seems the underlying ethos of the guy who designed the A4 was "why use 1 bolt when 6 will do"

the actual act of nail the bar to the car was dead easy but getting in there lol


anyway, to the point, I bought the bar off the bay of e and did come with a universal bypass relay, I've never been a big fan of these, always used dedicated kits in the past but the Audi needs coding?

anyone tell me what's involved there?

 

[EddyP]

I put a bypass relay in mine and it wasn't too hard. Found a diagram for the rear lighting and just worked from that.
I put the bypass relay on the nearside and then it only needed two cables over to the off side, one for the RH indicators and one for reverse or fog light IIRC.

The main issue with the wiring on the A4 is the same bulbs are used for the brake and rear lights, single filament bulb! It works at 5V for tail lights and 12V for brake lights, make sure your bypass relay can cope with this.

This might help

http://www.audizine.com/forum/showthread.php/493283-B7-avant-trailer-hitch-wiring-install