Rear light cluster - connection problem?

Hey guys,

Last time I asked for help with a problem it saved me about £500, so I'm hoping you'll come up trumps again.

When I test drove my A6 (56 plate) 6 months ago, the warning light came on for two bulbs on the rear n/s light cluster. The garage I bought it off said they tried changing the bulbs but that didn't fix it, so they had to change the whole cluster's circuit board or something. That was 6 months ago, the other day the warning light came on for two more bulbs in the same cluster. Mysteriously, the warning lights have stopped coming on now and the lights are all working again, without me doing anything.

Is this a common problem that I don't yet know about with these? Or is there another gremlin that's causing this intermittent problem that someone can suggest a solution to?

Check the bulb holder for corrosion. There's also a problem with bad earths on some cars aswell. (Do a search on here, there are some threads about it)

My '57 plate suffered from corroded holders and Were replaced under warranty.

The earth point is prone to burning on the 4F, I have done loads. I use contact cleaner and a small flat blade screw driver to clean the cluster fitting and I replace the terminal in the plug with a gold plated one which I keep in stock. Personally I think the size of terminal for the earth is too small for the current should the tail and fog lights be on for a long period. I have even seen these light units melt internally due to bulb heat and I have replaced many due to them being full of water that you cannot get out.

Thanks for that, I'll check them out tomorrow armed with some contact cleaner. There is some water/condensation in the cluster, not much, but possibly enough to cause corrosion over the course 5 years. I'll let you know if I spot anything untoward. Cheers.

I had a similar problem with intermittent failure of the rear indicator and the rear brake light. I went through the whole contact cleaning process without success (very frustrating). The front and front wing indicator worked fine but the rear was up the creek. Finally tracked it down to corrosion within the plug/socket which connects from the car to the back of the lamp holder. The pin that feeds the indicator and the brake light wad corroded. Cleaned it up and all is well again. It is yet another fault caused by the lack of waterproof sealing to the rear light assemblies. Thanks to all contributors who guided me towards the problem/solution.

Hi Guys
Ive got a similar problem to this. Intermittent NSR lamps (brake, light, indicator, reversing) all causing a warning light to come on. Turn the engine off and back on and its all fine again. I have replaced all the lamps with no success. Ive also checked for corrosion but found nothing. Ive seen somewhere about replacing the lamp holder? does anyone know where to get one and if so how much they are?

An outer tail light holder is about £30 from an Audi dealer but is is normally a burnt earth pin and socket.

Hi Crasher, i have the same earth problem in my rear lights (A6 2007) and every 3 or 4 months have file the black deposit off the earth connector to remedy. Where can I get some gold plated connectors and how do I fit them and does this provide a permanent fix?

I'd like to know that too. I've just had a first, successful, attempt at filing the corrosion off but I don't expect that I've effected a permanent solution!

I buy them from Wurth and VW door wires with terminals on them.