hey i was drivin my 2004 a6 2.7t today and the abs light and traction lights both came on but the car still drives fine. it has about 55,000 miles on it, does anyone know if this is gonna be a costly repair or is it just a sensor that needs to be fixed? its gonna snow here in a couple days so id like to make sure i can afford to fix it asap. thanks...

 

I don't know about the newer C5, but older ones had issues with brake switch which caused the lights to come on. It is a $20 fix if you DIY. I would try that before anything.