GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2006 🢒 GTO 🢒 Body 🢒 Lighting Systems 🢒 Headlamp Aiming

Visual Aiming Preparation Procedure

Important: Some state and local laws specify requirements for headlamp aim. All of these laws must be complied with when performing any headlamp aiming operations.

Headlamp aim should be checked:

    • When a new headlamp capsule is installed
    • If service or repairs to the front end area have, or may have, disturbed the headlamps or their mounting
    • If the vehicle will regularly carry an unusual load in the rear compartment or tow a trailer, these loads should be on the vehicle at the time of aiming the headlamps.
   • 
  • The area will consist of a level surface large enough to allow for a vehicle and an additional 5 m (16 ft) measured from face of lamps to the front of the aiming screen.
    •    • 
  • The screen will be 1.52 m (5 ft) high x 3.66 m (12 ft) wide with a matte white surface well shaded from extraneous light, and properly adjusted to the floor on which the vehicle stands. Provisions should be made to align the screen parallel with the vehicle.
    •    • 
  • The screen shall be provided with a fixed vertical centerline, two laterally adjustable vertical tapes, and one vertically adjustable horizontal tape.
    •    • 
  • If a regular commercial aiming screen is not available, the screen may consist of a vertical wall having a clear uninterrupted area approximately 1.83 m (6 ft) high and 3.66 m (12 ft) wide. The surface should be finished with a washable non-gloss white paint.

    • Prior to aiming the headlamps, the following steps must be taken:

    1. Remove any snow, ice or mud from the vehicle.
    2. The vehicle must have a full tank of gas.
    3. The spare tire is in place.
    4. Correct engine oil level.
    5. Stop all other work on the vehicle.
    6. If any service has been performed on the vehicle, make sure that all of the components are back in their original place.
    7. The vehicle must be on a level surface.

      8. Object Number: 418380 Size: SH
    8. The vehicle left tires must be aligned with the reference line extending from the screen with the headlamps aligned with the reference line.
    9. Inflate the tires to the proper pressure.
    10. Rock the vehicle in order to stabilize the suspension.
    11. Turn on the headlamps to low beam and observe the left and the top edges of the high intensity zone on the screen. The edges of the high intensity zone should fall within the specifications.

    Headlamp Aiming Procedure

      Important: DO NOT cover the headlamp, this may cause excessive heat build up.

    1. Open the hood.

      2. Object Number: 1757571 Size: SH
    2. At the screen, in conjunction with a flat horizontal floor (A). Park the vehicle immediately in front of the screen/wall and mark a horizontal line (B) that corresponds to the center of the low beam bulb.
    3. To check whether the mark is correctly positioned, turn on the headlamps.
    4. Put the vehicle into Reverse gear and move it straight back to that the front of the vehicle is 15 ft from the screen/wall.

      5. Important: The maximum allowable variation in vertical headlamp adjustment is 5 mm to either side.

    5. Aim the left headlamp to illuminate the line (1) as indicated. Aim the right headlamp so that it illuminates the line (2) as indicated. Both of these lines are to be 40 mm (1.57 in) on the headlamp horizontal center line (B).

      6. Object Number: 1379677 Size: SH

      Important: There is no allowance for horizontal adjustment. Headlamps are fixed to a horizontal centerline.

    6. Using a No. 2 Phillips head screwdriver, adjust the beam of the headlamp by rotating the adjusting screw (1) to raise the beam and counterclockwise to lower the beam.
    7. Adjust the other headlamp, if necessary.
    8. Turn the headlamps OFF.
    9. Close the hood.