Evening one and all. I need your help. Recently purchased a 2005 Audi A6 avant sline. My first ever Audi. Spent a small fortune on it getting it right but one problem has completely stumped everyone. The rear passenger light! When the lights are off we have peace and quiet, everything works, however, turn the headlights on and all hell breaks loose! Firstly we get a warning saying rear light not working. This is followed by a brief flash then another beep saying brake light does not work. The indicator works and the reverse light works but nothing else and the light cluster on the boot itself is really dim. So far I have found the fuse and replaced it, traced the wiring and can not see any breaks and all bulbs are brand new. The unit works sometimes but then I beeps and the lot goes mad! Checked the power and when it works it’s great when the head lights are off but turn them on...... you guessed it.... beep and there off again. Can anyone think of anything I have not tried. Audi want to replace the entire rear lighting loom at £800 plus fitting!!!! 🥴