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Headlamp Aiming Procedure

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  1. Align the left tires of the vehicle with the reference line extending from the screen with the headlamps aligned with the reference line.
  2. Remove any snow, ice or mud from the vehicle.
  3. The vehicle must be fully assembled and all other work stopped while the headlamp aiming is being done.
  4. The vehicle must contain one person or approximately 160 lb (73 kg).
  5. Tires should be properly inflated.
  6. Rock the vehicle to stabilize the suspension.
  7. Fig 1: Center Of Low Beam Bulb
    G01696753Courtesy of GENERAL MOTORS CORP.
  8. Measure from the floor to the center of the low beam bulb (2) on the vehicle.
  9. At the screen, measure from the floor and place the horizontal tape at the above measured distance.
  10. Fig 2: Measuring From Reference Line
    G01696754Courtesy of GENERAL MOTORS CORP.
  11. Measure from the reference line on the floor to the left headlamp bulb centerline.
  12. At the screen, measure from the reference line and place the vertical tape at the above measured distance.
  13. Measure from the reference line on the floor to the right headlamp bulb centerline.
  14. At the screen, measure from the reference line and place the vertical tape at the above measured distance.
  15. Turn the low beam headlamps ON.
  16. Fig 3: Vertical & Horizontal Adjustment
    G01696755Courtesy of GENERAL MOTORS CORP.
  17. The graphic shows the vertical (1) and horizontal (2) adjustments.

    Adjust the headlamps to the specifications required by state and local authorities.

    Ensure the horizontal adjustment scale is set to zero before adjusting the vertical aim.

  18. Fig 4: Beam Pattern
    G01696756Courtesy of GENERAL MOTORS CORP.
  19. The beam pattern must look as shown in the graphic.

    Important:  Do not place a cover directly in front of the headlamp assembly while the headlamp is ON.

  20. Adjust one headlamp at a time while blocking the light from the other. The cover must be away from the headlamp.

    The following list refers to the callouts in the graphic:

    • Distance from ground to low beam bulb centerline (1)
    • The ground line (2)
    • Horizontal centerline of the low beam headlamp (3)
    • Vertical centerline of the low beam headlamp (4)
    • Two degrees or 26.7 cm (10.5 in) (5) to the right of the vehicle centerline (4)