Park so that both the left and right headlights are precisely 25 feet from the wall.
Using your tape measure, find the exact middle of both the windshield & rear window and mark them with strips of tape, creating vertical center lines, front & rear.
Standing behind the car, now sight along those center lines, as if you were lining up sights on a rifle in a carnival shooting gallery. When center lines are aligned, you can locate the headlight centerline on the wall. Mark this with another strip of tape.
Now measure the distance between the headlight lenses, center to center. Divide this distance in half and measure that distance to the right of the centerline on the wall. Mark it with a vertical strip of tape. Do the same on the left side.
Finally, measure the distance from the ground to the center of each headlight lens; mark that distance on the wall with a horizontal strip of tape.
You should now have two crosses on the wall, with centers that correspond exactly to the center of each headlight lens.
Testing Your Beams:
Turn your headlights on low beam. The left edge of the bright spots on the wall should just touch the vertical bars of the crosses in the lower right quadrants. The top edge should just touch the horizontal bars.
Need a Show Me?
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