I've seen it quite a few times with tail lights. Brake light filament falls onto the running light filament, hit the brakes and it back feeds the running light system.
I've been lucky. guess I have calibrated eyes. never had headlights aimed by a shop. even got a CHP sticker at a CHP roadside inspection on my first old car in 1967 in upland ca route 66. on level surface, low beam. just look at the pattern on the wall and slowly back up. the pattern should drop slowly the further the distance. STOP. adjust to match height left and right. then on high beam all 4 should be about the same level. no fancy aimers needed. factory LED headlights (like my prius) have a lot of glare and I get flashed sometimes even though they are adjusted correctly and I've checked the aim!
The Jalopy Journal
