DIY – A guide to buy perfect bulb for your car headlights

So, you are driving in the pitch black night without the street lights and the visibility is negligible thanks to the age-old halogen lights which are asking for replacements. You go to the mechanic only to hear the exorbitant prices of the lights he suggested! Wouldn't it be better if you yourself know which bulb is better for your car and what wattage bulb do you actually need?

In our pursuit to hand-out all the necessary information related to cars, be it buying it or be it maintenance, we bring you a guide to select the right car bulb for your car headlights under our do-it-yourself/how-to series. Here are three things to consider when choosing a headlight bulb.

Types of bulb

While the basic setting of a car headlight is common across manufacturers, it's the bulb inside the headlights that makes the difference. Here are three different types of bulb that can be fitted inside a car headlight:

The most common type of bulb can be found in most of the automobile headlights. A halogen is made on the principle of a common household bulb and has a filament inside a glass element which burns in the vacuum to produce the light. The reason such bulbs are widely used is low cost and low maintenance.

The obvious choice for anyone looking for a bulb upgrade is the HID (High Intensity Discharge) lights. The HID was first introduced to the automotive segment in the mid 1990s and are widely used as the factory option for high end cars like BMW, Mercedes and Audi. So if your vehicle comes with a HID lamp, you have to replace if with HID light only. And if you are looking for an upgrade to HID from halogen, you need to fit a conversion kit as the HID bulbs require a different current.

As for the functioning, unlike the halogen bulbs, an HID bulb do not have any filament. Instead, they emit light by burning the xenon gas inside the glass, hence the name Xenon lights. The light produced by HID is much brighter as compared to the halogen with a statistically longer use life, and require less wattage while running.

 The latest addition to the list of bulbs are the LEDs or the Light emitting diodes. Although in use from 1900's, the LED technology never found its way to illuminate our roads, but was widely used as cabin lights, tail lights and other applications, commonly referred as the 'non-projection applications. It's only after the 2000 that the LEDs gain much popularity in projection applications like headlights.

LEDs are the simplest way of illumination and do not require any ballast, or any other special wiring. LEDs are simple diodes that are much more durable than both the halogen and HID bulbs. Similar to the HID bulbs, you need a conversion kit to install the LEDs if doesn't come as a factory equipment. LEDs are generally your most expensive bulb option.

Wattage

Be it the halogen bulb or be it the HID lamps, you need electricity to get them operational, which means they have a wattage associated with them. Simply put, the higher the wattage, more will be its intensity. A standard halogen bulb fitted car will have 55 watts and so you will need to replace it with a 55 watt bulb only.

If you decide to go higher, like a 120-150 watt bulb, you need a relay to supply the power, as higher watt means more strain on the car's electrical system, that can overheat the wires and hence cause damage. A standard HID bulb, on the other hand, runs at around 35 watts. It is not advised to increase the wattage in a HID system as it can easily blind the oncoming traffic. There is a restriction on the maximum wattage for your headlights in some countries.

Kelvin Rating

Ever heard your mechanic to replace a yellow bulb with a white light (or tube, as they commonly call it)? Well, the color of the light that a bulb emits is determined by the Kelvin rating. While we generally don't give it much consideration, it is of utmost importance for safety reasons and also for legal issues, depending on local motor laws.

Here's what different Kelvin ratings emit-

While the Kelvin rating has no effect on brightness, the change in color may make it appear brighter, like in the case of white light. But higher you go on the Kelvin scale, like the blue/ purple bulbs, they will not be as bright as the mid-range bulbs like yellow/white. As mentioned above, for safety and legal issues, most headlight bulbs are in the 3400K to 5000K range.

We hope you now know your headlights better!