i just bought a 2001 M3. the car has aftermarket angel eye rings in the headlight housing. The car is all wired up for them, and has a switch under the dash. The only way i can get any action out of them is if i turn the dome light on, and hit the switch. If i do that I get one side to blink? Anyone know how to trouble shoot these? Also only one of the ballast get really hot? The other stays ice cold... the one that gets hot doesnt turn on at all.

I know its a shot in the dark, but I want them to work... Or i need to get them the hell out of the car. :mad

Do you know which brand they are?

You could swap the ballasts to determine whether the one ballast that gets hot is actually bad (most likely it is). As far as the lights turning on only with the dome light, they could have been originally connected that way, or they were connected somewhere else as well (ECU, ignition, parking lights, fog lights, etc) and the fuse blew.

They are probably connected to the dome light so they do the fade in/out feature. The 'other' connector may have dropped off which explains why they only work with the dome light now.