Headlamp Features and Replacment Bulbs

Automobiles have come a long way since the sealed beam headlights of the 70s. Now many base model cars and trucks are outfitted with automated light control systems and fancy adaptive headlights that help the driver see better and farther than ever before. This article will point out some interesting features found on today’s automobiles and talk about the service, maintenance and repair of specific headlamp systems.

Advanced Headlight Features

One of the handiest advanced features found on cars today is the automatic headlight dimming system. It also made my top 5 useful factory car accessories list. This function automatically switches the headlights from high to low beams when a grille mounted ambient light sensor detects oncoming headlamps from another automobile. This feature includes a sensitivity adjustment for when ambient light situations mimic oncoming traffic.

Another useful feature that found its way from luxury cars to the family sedan would be an automatic light system. This feature includes several smaller features that automatically turn on the headlights in low light situations. A sub feature of the system is it allows the headlamps to stay on for a period of time after the vehicle is stopped and the ignition is turned off. This can temporarily illuminate a dark driveway or entrance to a home. After the timer has run its course, it automatically turns off the headlights.

Still currently available on mostly luxury automobiles I expect the adaptive headlight system to also find its way onto regular passenger cars and trucks in the future. The adaptive headlamp attempts to illuminate bends and turns in the road. The system responds to steering angle sensors and actually swivels the headlamps that are controlled by bidirectional motors. Although the amount of movement is limited to less than 20 degrees, it can still help illuminate dark corners of the road providing the driver with additional reaction time.

Diagnosing Headlight Problems

Just like spark plugs and extended life engine coolant, headlamps seem to last longer than they did on automobiles from decades past. In fact, it is likely when it comes time to replace the first bulb on your new automobile it will be the daytime running light bulb. This is simply because the running lights average more hours of on time. With that said, if a headlamp fails to illuminate when turned on, the most likely cause will be a burned-out bulb.

This is especially true if one bulb lights and the other side does not. Although it’s possible to have a circuit malfunction in one side, it is more likely for it to be a burned out filament in the lamp itself. To verify this condition it’s recommended to check for voltage and ground at the headlamp connector or socket. Depending on the degree of difficulty to gain access to the bulbs, another quick test method is to switch the bulb out with the working side to determine if the bulb has failed. Be sure to hold the headlamp by the connector to avoid getting fingerprints on the glass as this can reduce longevity.

Headlamp Replacement Bulbs

Since gaining access to the individual, headlight bulb can vary greatly between year makes and models the scope of this article doesn’t allow us to cover exact procedures, but we can talk about best practices and include tips for replacing headlamp bulbs. Some vehicle manufacturers design quick disconnect housings that are hinged together with removable pins that make difficult looking replacement much easier. Car manufacturers that design these into the automobile will often include a paragraph in the owner’s manual that explains how to take advantage of these features.

As a professional mechanic my main recommendation is to avoid temptation in trying to improve the headlamps that are included on your automobile. In other words, make sure the replacement bulb is the same type and part number as the one being removed. Automotive manufacturers employ engineers to determine the wattage, style and mounting location of their headlight bulbs. It is designed to work in harmony with the gauge of the wiring and the power supplied from the alternator and battery. Although brighter bulbs might be available for purchase this will not always relate to improved vision and could hamper the vision of drivers you share the road with.

Automotive lighting maintenance is an important procedure that can help improve visibility, but more importantly can help you be seen by others. In the example of a burned-out left side headlamp, drivers may believe the single headlight indicates a motorcycle is approaching. For this reason, any problems should be diagnosed immediately. Take this a step further and purchase a replacement headlight bulb for your specific model and keep it in the glove box. Teach all drivers of this automobile exactly how to install it so everyone is prepared to take action.