Locate Your Lights
Step one is to find out just how many interior light bulbs your vehicle has and where they are located. Probably best to do this in the evening, early morning or, at the very least, someplace shady. Once you’ve got that dealt with, open the passenger door, see the lights come on, and start looking and counting.
Most newer vehicles have at least a dome light located somewhere in the headliner of the interior roof and a couple of map lights usually mounted close to where the rearview mirror is. But many newer and higher-optioned cars also have map lights for the rear seat passengers, as well as lights in the lower part of the inside of the doors, so that could be four or six more bulbs. And an increasing number of cars the past few years have stepped up their style game by including accent or ambient lighting that illuminates the footwells or the console in between the front seats.
You might have a dozen or more car interior light bulbs. It’s probably best to have a piece of paper and a pencil, or maybe use the “notes” feature on your phone, to keep track of how many you have and where they are. Once you’ve done that, you need to find out what kind of bulb you’re dealing with in each case.
Wedge Base vs. Festoon Bulbs
There are two basic types. The type with a silver cap on both ends, like the one pictured above, is called a “festoon” bulb. The other type only has metal at the bottom — looking kind of like the tip of a knife or of a pair of closed scissors. That’s a “wedge base” bulb. To find out what you have, you need to get a look at the bulbs themselves, so use your electrical hand tools to remove any covers, maybe use a flashlight for the under-dash lights and see which you have (you may have some of both — but in different places) — and then add those to your notes. You’ll need to know which is which and how many of which you need when you go shopping. They’re not interchangeable.
If your car has incandescent bulbs (and most older cars do), you’ll probably notice an improvement just by switching to new bulbs of the same type. But — this can also be an opportunity to upgrade to LED bulbs. They give brighter light and last longer. Knowing what interior light bulbs your car uses will also be helpful if you run into a problem with your car’s interior lights.
Check out all the electrical system products available on NAPA Online or trust one of our 17,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on your vehicle’s interior lighting needs, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.
Photo courtesy of Wikimedia Commons.
Mike Hagerty is an automotive journalist whose work has been featured on radio, TV, in print and online since 1997. He's the Publisher and Editor of MikeHagertyCars.com, and contributes car reviews to the Los Altos Town Crier and losaltosonline.com. Previous outlets have included KFBK and KFBK.com in Sacramento, California, the ABC television affiliates and Hearst-Argyle and Emmis radio stations in Phoenix, Arizona; AAA magazines for Arizona, Oklahoma, Northwest Ohio, South Dakota and the Mountain West and BBCCars.com.