GM Service Manual Online
For 1990-2009 cars only

To replace a taillamp bulb, do the following:

       • 
    Object Number: 805787  Size: A3
  1. Stoplamp/Taillamp
  2.    • 
  3. Turn Signal Lamp/Taillamp
  4.    • 
  5. Back-Up Lamp
  1. Open the tailgate. See Tailgate for more information.

  2. Object Number: 805668  Size: A3
  3. Remove the two screws from the taillamp assembly.
  4. Remove the taillamp assembly.

  5. Object Number: 805788  Size: A2
  6. Press the release tab and turn the bulb socket counterclockwise to remove it from the taillamp housing.
  7. Pull the bulb straight out from the socket.
  8. Press a new bulb into the socket, insert it into the taillamp housing and turn the socket clockwise into the taillamp housing until it clicks.
  9. Reinstall the rear lamp assembly and tighten the screws.