I am very curious to know how does H7 type bulb run as both High beam and Low beam since I can only see one single filament. Which portion (top or bottom) of the bulb is running high/low beam? Also, I have heard the DRL in BMW is running as high beam, is that correct?
No mystery; 4-headlamp system with H7 bulbs in all 4 fixtures. The optics (reflectors. shielding) are different, is all. Many cars use the high beams as DRLs - but at reduced voltage when in DRL mode, greatly reducing the light intensity.