GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1998 🢒 Camaro 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Headlamp Aiming

Headlamp Aiming Screen Method

Aiming By Screen Method
   • 
  • To correct the horizontal aim use the adjusting screw located on the outer side of the headlamps.
    •    • 
  • To correct the vertical aim by use the adjusting screw located in the top center of the headlamps.
    •    • 
  • Use a specific aiming area in a darkened location. Ensure that the aiming area meets the followings:
    •    - The area used must accommodate the vehicle with a space of 7.6 m (25 ft) left over.
       - Measure the additional 7.6 m (25 ft) from the face of the headlamps to the front of the screen.
       - The floor that the vehicle rests on is level with the bottom of the screen.
       - If the floor is not level, then compensate for the unlevel floor.
       • 
    Object Number: 294749 Size: SH
  • Ensure that the aiming screen meets the following:
    •    - The screen (2) is 1.5 m (5 ft) high and 3.6 m (12 ft) wide.
       - The surface of the screen (2) is a matte white.
       - The screen (2) is well shaded from outside light.
       - The screen (2) is correctly adjusted to the floor on which the vehicle stands.
       - The following items are present:
       • A vertical center line (2)
       • A horizontal center line (4) for the center line of the lamps
       • A horizontally adjustable horizontal tape (3)
       • 2 laterally adjustable vertical tapes (9)

            Important: Adjust the horizontal lines or tape (3) on the screen (2) for each vehicle that you inspect. Vehicles of the same model and year may have different standing height for the headlamps.

       • 
  • Make provisions for moving the aiming screen in order to align the aiming screen parallel with the rear axle of the vehicle.
    •    - This will allow for a horizontal line (4) drawn to pass through the center point between the two headlamp capsules.
       - The horizontal line (4) will be drawn perpendicular from the center line of the screen (2).
       • 
  • Once you set up the screen (2) in a permanent location, paint a reference line (7) on the floor. The reference line (7) will identify the proper location of the headlamps when the headlamps are being aimed.
    •    • 
  • If a regular commercial aiming screen is not available, the screen may consist of the following items:
    •    • 
  • A vertical wall that has a clear, uninterrupted area.

    • Ensure that the area is 1.8 m (6 ft) high and 3.6 m (12 ft) wide

       • 
  • Ensure that the area is finished with a washable, nongloss white paint.

    • Vehicle Preparation

    Prepare the vehicle for inspecting the headlamp beam aim.

    1. Perform the following to ensure an accurate headlamp aim.
      2. 1.1. Completely assemble all of the components on the vehicle.
      1.2. Ensure that the fuel load is ½ tank or less.
      1.3. Ensure that the only other load in the vehicle is the driver.
      1.4. Mark the center of the front and rear windows with narrow tape.

      Use these sights to locate the center of the vehicle.

      1.5. Do this by moving the vehicle or the screen until the center line (2) of the screen comes into alignment with the two points.
      1.6. Close the doors.
      1.7. Rock the vehicle sideways in order to stabilize the suspension.
    2. Position the vehicle so that the vehicle is square with the aiming screen.
    3. Position the headlamps directly over the reference line (7) that you painted on the floor.
    4. Locate the vertical line (4) on the aiming screen so that the vertical lines meets the following criteria:
      5. • The vertical line is aligned with the center of the rear window.
      • The vertical line is over the hood.

    Domestic Low Beam

    Check the following for the low beam headlamps.


      Object Number: 294751 Size: SH
    1. With the low beams on, observe the beam's high intensity zone on the screen.
    2. To adjust the headlamp aim perform the following:
      3. • For the horizontal aim the left edge of the high intensity zone should be on the vertical axis (1), or within +102 mm (+4.0 in) (3), or (4) -102 mm (-4.0 in) of the vertical axis (1).
      • For the vertical aim the top edge of the high intensity zone should be on the horizontal axis (2), or within -63.5 mm (-2.5 in) (5), or +51 mm (+2.0 in) (6) of the horizontal axis (2).
    3. If the above specifications are not met adjust the headlamps accordingly.

    European Low Beam (Right Hand Rule of Road) (Export Only)

    Check the following for the European low beam headlamps.


      Object Number: 379384 Size: SH
    1. With the low beams on, observe the beam's high intensity zone on the screen.
    2. To adjust the headlamp aim perform the following:
      3. • For the horizontal aim the center beam's break point (3) should be on the vertical axis (1), or within -38.1 mm (-1.5 in) (5) or 38.1 mm (1.5 in) (4) of the vertical axis (1).
      • For the vertical aim set the beam's break point (3) at -92.25 mm (-3.75 in) (7) below the horizontal axis (2), or within -57.15 mm (-2.25 in) (8) or -171.45 mm (-6.75 in) (6) below the horizontal axis (2).
    3. If the above specifications are not met adjust the headlamps accordingly.

    United Kingdom (UK) and Japanese Low Beam (Left Hand Rule of Road) (Export Only)

    Check the following for the UK and Japanese low beam headlamps.


      Object Number: 379385 Size: SH
    1. With the low beams on, observe the beam's high intensity zone on the screen.
    2. To adjust the headlamp aim perform the following:
      3. • For the horizontal aim the center beam's break point (8) should be on the vertical axis (1), or within +38.1 mm (+1.5 in) (6) or -38.1 mm (-1.5 in) (7) of the vertical axis (1).
      • For the vertical aim set the beam's break point (3) at -92.25 mm (-3.75 in) (4) below the horizontal axis (2), or within -57.15 mm (-2.25 in) (3) or -171.45 mm (-6.75 in) (5) below the horizontal axis (2).
    3. If the above specifications are not met adjust the headlamps accordingly.

    Domestic and Export High Beam

    Check the following specifications for the high beam headlamps.


      Object Number: 294753 Size: SH
    1. With the headlamps on high beam, observe the center of the high intensity zone on the screen.

      2. Important: With composite headlamps (Chevrolet) it may not be necessary to aim the high beam lamps, the low beam adjustment may have taken care of the high beams.

    2. To adjust the headlamp aim perform the following:
      3. • For the horizontal aim the center beam's high intensity zone should be on the vertical axis (1), or within +102 mm (+4.0 in) (3), or (4) -102 mm (-4.0 in) of the vertical axis (1).
      • For the vertical aim the center beam's high intensity zone should be on the horizontal axis (2), or within -63.5 mm (-2.5 in) (5), or +51 mm (+2.0 in) (6) of the horizontal axis (2).

    Headlamp Aiming Alternate Procedure

    Tools Required

    J 25300-D Headlamp Aimer (Mechanical Type), or equivalent

    Important: When using headlamp aiming equipment which attaches to the headlamps with a suction cup type devise, DO NOT leave the headlamps on while the equipment is attached. On vehicles with plastic headlamps (body styled composite or sealed beam) having the headlamps illuminated when the equipment is attached, may cause heat build-up combined with the suction cup may cause the plastic headlamp lens to become distorted, requiring lamp replacement.

    1. Prepare the vehicle for checking beam aim as follows:
      2. • Place the vehicle on a flat surface.
      • Remove large amounts of mud or ice from the underside of the fenders, if necessary.
      • Check whether tires are noticeably deflated and inflate if necessary.
      • Ensure there is no load in the vehicle other than the driver.
      • Rock the vehicle sideways to stabilize the suspension.
      • Clean the headlamp lenses and aiming pads.
    2. Refer to the manufacture's instruction for the correct operation of the headlamp aiming equipment.