When you replace headlights, you must pay attention to the way you've aimed them. In other words, don't point your headlights to the side of the road because you won't be able to see a single thing (i.e. deer, car or pedestrian) in front of you. And, oncoming drivers will be totally blinded by your misdirected beam.
If you replace headlights underneath the bumper, you're probably installing new fog lights. Minimizing glare for you and for the oncoming driver is key, which means as much light as possible needs to be aimed at the road. Drive lights, on the other hand, are typically mounted above the front bumper to create extra high-beam light.
When you've completed the necessary steps to replace headlights, you'll want to test them for proper aiming. Get out your tape measure and park your car on a level surface 25 feet away from a wall. Shine those lights, then measure the distance between the center of the light to the ground. Mark that distance on the wall. Fog lights are aimed when the top of their beam is 4 inches below the center mark on the wall. Driving lights should be 1.5 inches below.
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