high intensity discharge
H4 twin filament.
On a four headlight system there are two filaments for the inner lights. They have a filament for a high beam and one for a low beam.
It sounds like your low beam filament in the headlight bulb is gone. Try replacing the headlight bulb.
One filament of bulb burned out (double filamented bulb) Replace bulb
A.C. in your home and D.C. in your car.
Hi beam lights only the High brightness filament of the headlight.Lo beam lights only the Low brightness filament of the headlight.DRL lights only the High brightness filament of the headlight, but at reduced current.Do you see the pattern?
Depending on the model year, you probably have one low beam bulb and one high beam bulb in each headlight.... unlike 90-94 323s that had one 2-filament bulb in each headlight.
Yes, but not more than 13 - 15 volts, or the headlight filament will burn out.
Probably the low beam filament in the dual beam headlight lamp is burnt out. See sources and related links below for more information on the headlight lamp.
There are two filaments in a car headlight. One is higher than the other. When you dip the lights, one filament turns off and the other turns on.
The headlight has two filaments. One for the high beam and one for the low beam. The most likely reason the high beam is out is because the high beam filament is broken. Replace the bulb and it should fix it.
The Filament