I bought a used (2005) A4 Avant 2.0TDI last June. It seemed to be in good nick, but my first problem started when I got back from a fortnight's holiday in August to a dead battery. My usual independant Audi garage couldn't find a fault, so I soldiered on for a few weeks, until I left it a few days and it nearly didn't start again.

I took the car to an independent auto-electrician, who said there was a 1/4A current drain, and that it was probably a fault with the "onboard supply control" or an associated unit, which would have to be repaired by an Audi service centre.

My last dealings (several years ago) with Bradford Audi were not good. They charged me £200 for a service which turned out to be just an oil/filter change. I found this out because my car developed a rattle during the service, and I asked what they'd done. They tried to charge me £660 to fix the rattle, which they thought might be worn engine mountings. It turned out to be a bent truss rod, resting against the engine's underside, presumably because they'd dropped it on something. They pleaded innocent. You can see why I now use an independant garage.

So, you can imagine that I wasn't keen to take my new car to Bradford Audi. But I had no choice, wthout a long journey to another town.

After a day, they told me that they'd tried another car's onboard supply control in my car and this had worked. I was told that the old unit had failed to shut down the lighting circuit, hence the current drain. I would have to wait another day for a replacement unit. The repair cost £365 in parts and labour (about 50/50).

The car seemed fine. It certainly started much brighter. But, 10 days later, while driving at night, the skid indicator came on for no reason, the LED displays flickered, the dial backlights went out, and the air-con turned itself off. The car seemed otherwise okay.

As this was just before Christmas, I carried on driving it for a couple of weeks - every time it starting up fine and the system failure usually starting after about 10 minutes' driving (more usually with the headlights on).

Last week, I took it back to Audi, expecting their onboard supply control to be in need of replacement. However, they told me the fault was now with the dash, and estimated a further cost of £640!


Sorry for the epic tale. I'm really lost for what to do. Does it seem likely that another fault has developed so soon after their repair? Am I at the mercy of whatever Audi decides? Do I just bend over, and give them my wallet?

Advice would be gratefully accepted!