Sometimes they sin on the generator and voltage regulator, there is some truth in it: malfunctions of these devices are noticeable by "movement" luminous flux, as if obeying the number of engine revolutions. It is clear that the unimportant operation of the generator and voltage regulator affects not only the efficiency of the headlights - first of all, the battery suffers, either not receiving a full charge, or vice versa - receiving it in excess, from which "boils" electrolyte. Headlights in this case play only the role of an indicator, although excess voltage greatly reduces the life of the lamps. Constant dim radiation occurs for other reasons: either the reflector is heavily polluted or corroded, or the inner surface of the lamp bulb is covered with a dark coating.
If the durability of the reflector depends on many factors, which we will talk about later, then even a perfectly serviceable lamp "gaining" dark plaque for some 30-50 thousand kilometers. Its effectiveness in this case is 20 percent lower than the new one.
Reflector "lives" longer. In modern cars, the reflector and headlight glass are, so to speak, an indivisible whole, which, of course, first of all provides the most optimal light beam, and secondly - tightness. It was the lack of tightness that contributed to the penetration of dust into the headlight, which then burned on the reflector and reduced its light output. The same thing happened with moisture, which actively condensed on the reflector, which caused corrosion.
About five years ago, they tried to fight corrosion in some incredible way, pouring red brake fluid into the headlight. The fashion for this rather harmful than useful undertaking has passed, but another extreme has appeared - plexiglass "glasses" on glass. In addition to the fact that such protection reduces light output, "smearing" the direction of the rays, it causes strong heating and burning of the reflector. In this case, what is the use of glass protected from stones, if the reflector suffers - it is not clear, especially, as already mentioned, glass and reflector now represent an indivisible whole? By the way, so there is no point in buying "lens" separately: good light from such a headlight can never be achieved.
Finally, with regard to adjustments. Even the best headlights equipped with halogen lamps can be useless on the road if they are adjusted anyhow. Not everyone, and not always, has the opportunity to make adjustments on the stand. Therefore, very good results are given by old, well-tested methods "home" adjustments. The car is installed on a flat area, 30 meters are measured and put on a mark, say, a brick. One of the headlights, switched on to the dipped beam, is hung with something, and in the second, the adjusting screws are rotated so that the illumination border is vertically brought to the delivered brick. Do the same with the other headlight. The main beam is adjusted in the horizontal direction, but already without a brick: it is important to ensure that the beams from both headlights do not bifurcate and converge in the middle.
Halogen lamps
The main reason for the rapid failure of halogen lamps in cars is the large current flowing through the lamp at the moment of switching on, since the resistance of its filament in a cold state is many times less than when it is heated.
In this regard, it is recommended to limit the starting current with the help of an additional resistor connected in series with the filaments of halogen lamps. After turning on the lamp, this resistance is short-circuited using a voltage relay installed in parallel with the lamp.
The disadvantage of such devices is the need to use one or two electromagnetic parts, which are not sufficiently reliable, especially in the conditions of a car experiencing vibration. In addition, at the moment of switching on, there is still an abrupt increase in current, although to a smaller value than with conventional lamp switching circuits.
Specialists have developed a non-contact device that does not require the use of a relay and provides a smooth increase in current in the lamp. The device consists of an additional resistor R1, two diodes VD1 and VD2 and an electrolytic capacitor C.
When the dipped beam filament is turned on, a positive potential is applied to clamp 1. In this case, the VD1 diode connects the capacitor C in parallel with the lamp filament, and the resistor R1 in series with it.
When the high beam thread is turned on, a positive potential is applied to terminal 2 and capacitor C is connected in parallel to the high beam thread through the VD2 diode.
With this connection scheme, the voltage on the lamps EL1 and EL2 increases smoothly.
The resistance of the cold filaments of ordinary automobile low and high beam lamps is approximately an order of magnitude lower than their resistance in a heated state. The heating time constant of the lamp filament is 0.0014-0.003 s.
To eliminate an unacceptably high current during the lamp on, it is necessary that the rate of increase in the resistance of the lamp filament be greater than the rate of voltage increase. This is achieved by installing electrolytic capacitors with a capacity of 4000-6000 microfarads, a nominal voltage of 25 V.
If you use these tips, then along with an increase in the life of the lamps, the life of the battery will also be extended due to a decrease in the starting current and an increase in the smoothness of its increase.