Some drivers consider the recommendation to replace the car bulbs in pairs to be an unnecessary investment. However, the health and even life of all road users can be at stake if small savings are made.
Modern car headlights are designed to improve visibility on the road. The revolutionary patent was the idea of the Philips brand, which introduced xenon bulbs for series production (on the BMW 7 Series models from 1991). Nowadays, more and more new cars are equipped with bulbs that are based on LED technology and even laser diodes (more on the development of light sources: link ).
However, cars that use old models of headlights and halogen bulbs are still mostly on the road. Their drivers often face a dilemma: to replace one light bulb witch is burned or both bulbs, including the light bulb that is still working. The answer is always the same: headlight bulbs should always be replaced in pairs. Why?
Each item is characterized by a certain technical lifespan. This is not always the same, but in the case of a pair of light bulbs, it can be assumed that when one burns, the other is also nearing the end of its life. In this situation, the driver must restore the efficiency of car bulbs, which is not a simple task for current models. In addition, the replacement of the bulbs may require the removal of the protective covers from the engine compartment and even the wheel spring covers. Efforts for this task will need to be repeated soon. And that’s not all.
“As it works, the halogen bulbs lose their lighting parameters. As a result, not only the lighting intensity decreases, but also the length of the light beam that falls on the road – ”says Wioletta Pasionek, Marketing Manager for Central Europe at Lumileds Poland, Philips’ only licensed manufacturer and distributor of car bulbs.
When replacing light bulbs, remember a few important principles. First of all, the light bulb should not be touched with bare fingers. Traces on the glass can lead to distortion of the light beam. Second, new light bulbs must be installed correctly. Reversing the position of the filament can lead to incorrect light reflection in the direction of the road, to the side of the road or even to the sky, leaving key areas in the dark. Thirdly, the structure of the headlight is adapted to the traffic on the left or right side, which means the asymmetry of the light beam – shorter at the axis of the road and longer at the sidewalk. This distribution allows the driver to obtain an optimal field of vision and, on the other hand, does not blind the other traffic participants. Replacing a single bulb does not allow these requirements to be met. Something else?
“After replacing the bulbs, the headlights must be adjusted accordingly. Even a small deviation can lead to blinding of other road users “- adds Wioletta Pasionek from Lumileds Poland -” It must be remembered that vision deteriorates with age. According to specialist research, every 12 years, our ability to cope with blinding light decreases by up to 50% ”.
The last argument for replacing bulbs in pairs is their version and manufacturer. We don’t always remember if we last installed a traditional light bulb or a version with a longer or more intense light beam. The use of different products with different specifications will further increase the disproportion of lighting properties and therefore reduce the level of road safety.
It is recommended to choose known car bulb manufacturers. They guarantee the use of high quality materials and the accuracy of performance specified in the applicable standards and approvals. In addition, it affects the life of light bulbs and therefore their frequency of replacement.