Halogen head lights flashing when cold????

[outsideline]

hi there since buying my audi b7 170dpf quattro i have has an underlieing problem with the head lights....

when the car is cold (been stood for quite a few hours outside work) i start the car, put the head lights on and for the first couple of minute the lights flash bright and dull??? ( just the headlights not interior lights, although you can tell something is not right they do flicker )

im not sure whether its connected to the brake light switch??? but for definate there is something clicking behind the headlight switch on the dash, possible relay??? seems to do it when i press the brake?????

once the car has run for a couple of minutes the problem goes and runs fine from there on in???

im a mechanic as trade so have pritty good knowledge of most manufactors but never come come across this???

any thought or help would be well appriciated. i have run numerous diognostic checks with car soft, vag com and nothing shows up.

thanks people.... chris

 

[Brennan]

Quite strange this, tonight, i noticed my passenger headlight (dipped beam) flicker a bit, going dull and then bright again, once i drove on down the road a bit it was fine. I have a B8, not sure if this would be the same issue. Thing that baffled me is that like yours, mine is also Halogen, i know that Xenon lights have a tendancy to flicker due to a failing ballast on them, not sure what it would be on a halogen headlight.

Worried me a bit, its never happened before