Checking Headlight Aim

SD DM 22.01.01
  1. Park the vehicle on a level surface, 25 ft (7.6 m) away from, and perpendicular to, a vertical screen or wall. Shut down the engine and set the parking brake. Chock the tires.
  2. Each headlight has a height adjusting dot. See Fig.. Measure the distance from the ground to the height adjusting dot on each headlight (see Fig., Item A). Note those distances.

    Measure beam height from the ground to the small dot roughly in the center of the headlight lens.

    Fig. 1, Headlight Beam Height Adjusting Dot

    • Measure the distance from the ground to the center of each headlight bulb.

    • Mark where the center of each headlight projection should appear.

    1. Screen or Wall

    2. Center of Right-Hand Headlight Projection

    3. Center of Left-Hand Headlight Projection

    Fig. 2, Headlight Aiming Screen/Wall

  3. On the screen or wall, mark the locations of each headlight bulb center using the distances found in step 2. See Fig., Items 2 and 3.
  4. Turn on the low-beam headlights.
  5. Check the vertical adjustment of the low beams. The center of each beam projection should fall on or near the marks made during step 3. See Fig..
    1. Low-Beam Angle Upper Limit

    2. Ideal Low-Beam Projection

    3. Low-Beam Angle Lower Limit

    Fig. 3, Vertical Low-Beam Headlight Variation Limits

  6. Use Table. to determine the maximum vertical distance allowable between the marks on the wall and the center of each low-beam projection. If the distance between either projection center and the mark made on the wall or screen is greater than the maximum distance given in Table., adjust the vertical positioning of that headlight.

    Table 1, Vertical Low-Beam Headlight Variation Limits

    Vertical Low-Beam Headlight Variation Limits

    Distance Between Ground and Headlight: in (mm)

    Desired Variation (see Fig., Item 2): in (mm)

    Upper Limit (see Fig., Item 1): in (mm) up

    Lower Limit (see Fig., Item 3): in (mm) down

    22–36 (560–900)

    0

    3.9 (100)

    3.9 (100)

    36–48 (900–1200)

    2 (50) down

    2 (50)

    6 (150)

    48–54 (1200–1400)

    4 (101.6) down

    1.6 (40)

    6.5 (165)

      Table 1, Vertical Low-Beam Headlight Variation Limits

    Note:
    Document Number: 0000123559
    Manual Publication Date: 2025-01-23
    Topic Publication Date: 2025-01-23