GM Service Manual Online
For 1990-2009 cars only

To change a CHMSL bulb, do the following:

  1. Remove the CHMSL cover by pulling down on the cover edges from inside the vehicle.

  2. Object Number: 1225899  Size: B3
  3. Turn the bulb socket counterclockwise to remove it.
  4. Replace with the appropriate bulb.
  5. Reinstall the bulb socket by turning it clockwise.
  6. Replace the cover.