How to Adjust HID Headlightsby Steve Bradley
HID headlights provide a more powerful focus and long-lasting light beam than traditional headlight bulbs. These newer light bulbs are easily recognized by their blue tint and strong shine. Because of their strength, though, it is important to have them properly aligned. If a headlight is not adjusted in the correct manner, not only will your line of sight be diminished, but oncoming traffic my be blinded. Luckily, fixing this problem isn't much more difficult than taking a few measurements and adjusting a few screws.
Load the automobile with enough weight to approximate the normal nighttime driving weight. Weight will affect the angle of the light beams, so it is important that this is correct. Things to consider are the trunk, back and passenger seats as well as having a partner sit in the driver's seat representing you.
Pull the automobile within a foot of a large wall, with 25 feet of room to back up. Mark the wall with the masking tape along the vertical and horizontal axis points of the headlights. Start with a 6-foot strip of tape from the center point of the driver's side headlight to the center of the passenger's side light. Then take two 6-inch pieces of tape and put a vertical mark in front of each light, creating a cross-shaped mark that will act as a bull's eye.
Back the auto up 25 feet. Turn the HID headlights on so that they shine against the wall. Inspect the light beams. Both headlights should land 2 inches below the 6-foot strip of tape. The passenger's side headlight should also land directly on the shorter strip, but the driver's side should hit 2 inches to the right. This indicates that the beam will not hit oncoming traffic.
Open the hood and go to the rear of the headlight assembly. At the top and center of the headlight will be a small adjusting screw that controls the light's vertical axis. Use a screwdriver to adjust this until the light hits the desired spot. Along one of the sides will be a second screw for the horizontal axis. Adjust this screw as well.
Items you will need
- Masking tape
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