Step 1: Replace the bulb
1 of 1
Start with the obvious suspect
Many new car bulbs are easily accessed from under the hood by turning a retaining ring and pulling the bulb socket out, but if you have to access the bulb by removing a lens (see your owner's manual), you may need to buy a “torxrdquo tip screwdriver. Remove the old bulb and insert the new bulb. Don't touch the glass of the bulb with your bare hands because the oils on your skin can cause the bulb to fail. Reinsert the socket into the headlamp housing and turn on your lights. If they work, you're done; if they don't, go on to the next step.
When a headlight goes out, the problem is usually a bad bulb, which is easily replaced. However, the problem could also be a corroded socket or a bad wire. Keep in mind that when several lights are out, such as both headlamps or both taillights, the problem is most likely a fuse. If the fuse is bad, you can replace it and most likely be on your way.
In this article, we'll show you how to replace the bulb, and if that fails, we'll show you how to diagnose a bad socket and probe the wiring with a simple 12-volt automotive test light.