Help. Tow bar wiring A4 Avant

[RobsA4]

Can anyone point me in the direction of a retail outlet/web that sells a suitable "Clip in " wiring for use with my tow bar. Audi have quoted £250!! There must be an aftermarket supplier.
Thanks Rob

[GeorgeE]

Just fitted a towbar myself. Local dealer quoted £125 for the towbar (non removable swan neck version - turns out it is actually a Brink part) and £75 for the wiring kit. The wiring kit is an absolute bstd, on my 2003 A4 Avant it involved running cables to the front of the vehicle down the wiring channels under the floor on each side (translates to take all teh seats out and most of the side trim), so although it technically "clips in", it would have been far less hassle to do what all the towbar fitters do and stick a bypass relay in the back spliced into the existing lights.

After rigging it I discovered there was an additional ECU required to get it all to work at £130 and the dealer hadn't bothered to supply it or tell me about it!

[RobsA4]

Thanks...............
I will do the easy option!

[Graham Shill]

Hi, very interesting reading.

I used to fit towbars on my own cars years ago prior to the ECU days.
I now want to fit a towbar on my 02 Audi A4 quattro and trying to get to grips with all the wiring options and tales that go with it.
Audi dealers say they cannot advise on DIY fitting as they will become liable in the event of future problems.
Some people say that cutting into the wiring with scotch lock fittings can cause electrical fires and ECU problems so use a manufactures purpouse made wiring loom that costs 1million quid and then you have to take half the car apart to fit it.

All suggestions welcome

[Ben]

fitted my own to my golf 5. there is a how to guide and a research thread.

[GeorgeE]

Hi, very interesting reading.

I used to fit towbars on my own cars years ago prior to the ECU days.
I now want to fit a towbar on my 02 Audi A4 quattro and trying to get to grips with all the wiring options and tales that go with it.
Audi dealers say they cannot advise on DIY fitting as they will become liable in the event of future problems.
Some people say that cutting into the wiring with scotch lock fittings can cause electrical fires and ECU problems so use a manufactures purpouse made wiring loom that costs 1million quid and then you have to take half the car apart to fit it.

All suggestions welcome

OK, firstly, Scotchlocks are the work of the devil. For a really reliable connection solder and heatshrink are the way forward, as a backup a proper crimp connector. But NEVER scotchlocks.

OK, to your main point. Buy a 6 way (though they seem to be 7 way to allow for reverse if you are doing a secondary connector) bypass relay. This isolates your trailer from the vehicle electrics (you run a permenant live to the relay box and it uses that to power the trailer rather than the lighting loom on the car). This will also provide the warning beep for the indicators.

The only drawback with this method is that you get a warning beep for the indicators instead of a nice dash board display (for that you need the "proper" Audi loom). Having done it both ways I would never put in the Audi loom again, there is far more chance of damaging something with the amount of the vehicle you need to dismantle. The relay is all done behind the light cluster, quick and simple.

[avanted]

This is what i did on my A6,as i couldn't get a price to wire up from audi under 3-400 quid, i would prefer the dash lights but..........

[ray78dtv]

Sounds like a horendous job. I have a loom from mkek but no wiring instructions. Do not know what to do for the best now I have read your stories.

regards ray78dtv

[defever]

It seems that rear washer jet leak under the boot or by the tailgate compartment is quite common with VAG so just a little warning...

I recently bought B5 A4 Avant and it already had tow bar and its lighting bypass TAB7AS installed, I thought BONUS! On my way home from a dealer, I thought I'd try rear washer; didn't work. Tried again, didn't work. I left it.

But then this strange high pitch beep came on INSIDE the car randomly and I thought, I just bought this car...

It turned out that the bypass was swimming in the bottom of the tailgate compartment filled with washer fluid... I had to cut the wiring to make it shut up. My loyal garage said they'll rewire it FoC (5min job) if I manage to clear it from water ingress or buy another bypass (it's only £20.00 or so).

SO, I hope no one is as stupid as me, but just a little advice NOT TO LEAVE the bypass (or any electrical stuff) at the bottom of the boot or tailgate compartment in case you get a pool of fluid...!!

[ray78dtv]

Sounds like a horendous job. I have a loom from mkek but no wiring instructions. Do not know what to do for the best now I have read your stories.

regards ray78dtv

Got sorted in the end. If your car is an A4 i will send wiring instructions i got from mkek to you. All i need is your address. Having said that i still have their email so may be able to email them to you if you give me your email address. Do not know if you can pass this info on in private though as i have not used the forum before. instructions are very detailed and cover all A4 of my era.

regards ray78dtv