For 1990-2009 cars

Aim the headlamps for proper illumination of the road. Inspect the headlamp aim under the following conditions:

• | When a new headlamp assembly is installed

• | If service or repairs to the front end area have (or may have) disturbed the headlamps or the mounting

Headlamp focus is set when the unit is made. No adjustment for focus is necessary or possible.

Important: Some state or province and local laws specify requirements for headlamp aim. Follow those laws.

Horizontal aim is performed by an adjusting screw on the inboard side of the headlamp assembly. Vertical aim is performed by an adjusting screw in the upper outboard area. When aiming the headlamps, follow the instructions below.

### Aim Preparation

In order to prepare the vehicle for aiming the headlamps, perform the following steps:

• | Completely assemble all of the components on the vehicle.

• | Place the vehicle on a level pad or surface.

• | Stop all unnecessary operations or work on the vehicle that affects the vehicle trim.

• | Close the doors.

• | Rock the vehicle to stabilize the suspension.

• | Ensure that the fuel level is full.

• | Ensure that the tires are inflated to the proper pressure.

• | Ensure that the driver or a similar weight (approximately 165 lb) is in the vehicle drivers seat.

### Location

Ensure that the area is darkened and large enough in order to allow for the vehicle and an additional 7.62 m (25 ft). The distance for this procedure is measured from the face of the headlamps to the front of the screen. Ensure that the floor on which the vehicle rests is level with the bottom of the screen. Compensate for the floor if the floor is not level.

### Aiming Screen

If you are using a screen, ensure that the following criteria is met:

• | The screen is at least 1.52 m (5 ft) high by 3.66 m (12 ft) wide

• | The screen has a matte white surface well shaded from ambient light

• | The screen is properly adjusted to the floor on which the vehicle stands

• | The screen is movable

• | The screen can be aligned parallel with the rear axle of the vehicle

Position the screen in order to ensure that a horizontal line will pass an equal distance midway between the two headlamps.

Ensure that the screen provides the following features:

• | A vertical centerline

• | Two laterally adjustable vertical tapes

• | One vertically adjustable horizontal tape

If a regular commercial aiming screen is not available, use a wall having a clear uninterrupted area at least 1.83 m (6 ft) high by 3.66 m (12 ft) wide. Ensure that the surface is finished with a washable no-gloss white paint.

After the aiming screen is set up and located, paint or tape a reference line on the floor 7.62 m (25 ft) from the screen. Park the vehicle with the front of the headlamps directly over the reference line.

### Visual Procedure - Alero or Grand Am

1. Prepare the vehicle. Refer to Aim Preparation.
2. Park the vehicle square with the screen. Locate the headlamps directly over the reference line.
3. Ensure that all the components are in place if other work has been done on the vehicle.
4. Use the following procedure in order to line up the centerline of the vehicle with the centerline (2, 3) of the aiming screen:

4.1. | Mark the vertical center of the vehicle and the front windows using tape.

4.2. | Use these lines as sights in order to line up the centerline of the vehicle and the screen.

5. Adjust the vertical tapes on the screen to match the vertical centerline (1) of each lamp. Measure the distance from the centerline of the vehicle to the centerline of a low beam lamp.
6. Adjust the horizontal tapes (2) on the screen to match the horizontal centerline of the low beam headlamp. Measure the height from the floor to the center of a low beam.
7. Turn on the low beam lamps. Adjust the headlamps in the following manner:

7.1. | The left edge of the high intensity zone on the screen for the low beams is on the vertical line (5) for each side.

7.2. | The top edge of the high intensity zone on the screen for the low beam is on the horizontal line (2) for each side.

### Mechanical Aiming Procedure - Alero

1. Alero has a headlamp system equipped with horizontal and vertical aim indicators. The vertical and horizontal aim indicators may not fall exactly on the "0" marks on their scales. The headlamp aiming device is under the hood, near the headlamps.
2. Prepare the vehicle. Refer to aim preparation.
3. Start with the horizontal aim. Adjustment screws can be turned with an E8 TORX® socket (or T15 TORX® screwdriver). Once horizontal aim is adjusted, then adjust the vertical aim.
4. Turn the horizontal aiming screw (2) until the indicator is lined up with zero.
5. Turn the vertical aiming screw (3) until the level bubble is lined up with zero.
6. Complete the aiming procedure by using the visual procedure.

### Mechanical Aiming Procedure - Grand Am

#### Tools Required

J 25300-A Headlamp Aimer and Adapters

1. Prepare the vehicle. Refer to Aim Preparation.
2. Use the universal aimer on a level floor. Calibrate the universal aimer for floor slope, if necessary.
3. Select and assemble the universal adapter (1) that fits the aiming pad pattern on the lens of the headlamp.
4. Move the adjustment rods (2) to the number that corresponds with the number located on the headlamp lens.
5. Attach the adapters. Use the correct adapter with the correct side aimer.
6. Place the aimers (3) with the adapters on to their respective sides. Ensure that all of the adjustment rods are contact the aiming pads. Add or remove an extension stud, if necessary.
7. Aim the headlamps (1) according to the instructions included in the J 25300-A .