2003 GMC Sierra 1500 Pickup Owner's Manual - Page 442

Pickup Box Identification and Fender Marker Lamps 1. Remove the screws and lamp assembly. 2. Unplug the lamp assembly harness. 3. Gently pry the individual lamp from the lamp housing. 4. Unplug the lamp. 5. Plug in a new lamp and snap it into the housing. 6. Reinstall the lamp housing. Taillamps 1. Open the tailgate. 4. If a CHMSL bulb is replaced, put the new bulb into the socket and press it in until it is tight. If a cargo lamp is replaced, put a new cargo lamp bulb into the socket and press it in until it is tight before turning the socket counterclockwise. 5. Put the bulb holder back plate into the lamp housing. 2. Remove the two rear lamp assembly screws near the tailgate latch and pull out the lamp assembly. 6. Reinstall the lamp assembly and tighten the screws. 5-67