GM Service Manual Online
For 1990-2009 cars only

The front fog lamps must be aimed for proper illumination of the road. The front fog lamp aim should be checked when a new front fog lamp assembly is installed, or if service or repairs in the front end area may have disturbed the front fog lamp mounting.

Preparation Procedure

Important: Horizontal aim is not adjustable on this vehicle. Vertical aim is done by an adjusting nut located on the rear of the fog lamp. Prior to aiming the headlamps, perform the following steps:

  1. Completely assemble all of the components on the vehicle.
  2. Place the vehicle on a level surface.
  3. Stop all unnecessary operations or work on the vehicle that affect the vehicle trim.
  4. Close the doors and verify that the luggage compartment is empty.
  5. Stabilize the suspension by rocking the vehicle sideways.
  6. Ensure that the fuel level is full.
  7. Ensure that the tires are inflated to the proper pressure.
  8. Ensure that the driver or a similar weight, approximately 75 kg (165 lbs) is in the vehicle driver seat.

Aiming Procedure


    Object Number: 276650  Size: SH
  1. Park the vehicle 7.6 m (25 ft) away from the target screen.
  2. Measure from the center of the fog lamp to the ground line. Using this measurement, mark the horizontal centerline (2) of the fog lamp on the target screen directly in front of the vehicle.
  3. Turn ON the fog lamps. The top of the fog lamp beam image (4) on the target screen should be 102 mm (4 in) below the center of the fog lamp lens height.

  4. Object Number: 623939  Size: SH
  5. Reach under the rear lower edge of the front fascia to access the fog lamp vertical adjustment nut.
  6. Adjust the fog lamp as required, using the adjusting nut on the rear of the fog lamp.
  7. Turn OFF the fog lamps.