Incandescent lamps are subject to wear. They must be replaced every 2 years, even if they are still intact. This does not apply to H4 lamps (halogen lamps) main headlights, they last much longer and are replaced only in case of failure. A lamp with reduced brightness is detected by a black coating on a glass bulb. Switch off the switch of the relevant consumer before replacing the lamp.
Attention! Do not touch the lamp glass with your fingers. Fingerprints darken the lamp and deposit on the reflector due to the heat. Be sure to use a lamp of the same design. If there are stains on the glass of the lamp, remove them with a cloth with alcohol.