How to Fix the Back Tail Light on a 2003 Avalanche

The 2003 Chevy Avalanche uses a combination light assembly on the rear of the truck. Changing or fixing a lamp in the assembly requires removal of the entire housing to access the light sockets and bulbs. Without properly functioning taillights, drivers behind you have no way to know if you are stopping, turning or backing up. The bulb used for the stoplight, running light and turn signal of the Avalanche, a 3057, is readily available at any auto parts store as well as the dealer and most major department stores that have automotive departments.

Difficulty: EasyInstructionsThings You'll Need:

Phillips-head screwdriver

Step 1
Open the tailgate of your Chevy Avalanche and lower it against the support cables. The tailgate makes a great work area during this process.
Step 2
Locate the two mounting screws on the inside edge of the taillight assembly. They screw in from the side just above and below the latch for the tailgate. Remove the screws with a Phillips-head screwdriver.
Step 3
Grasp the taillight housing on either side with your hands and pull it straight out of the body far enough to access the sockets and bulbs on the back of the housing. Turn the socket for the bulb you are replacing counterclockwise about ¼ of a turn and pull it straight out of the assembly.
Step 4
Remove the bulb from the socket by pulling it straight out of the socket. Install a new bulb in the socket, pushing it in until it fully seats in the socket.
Step 5
Insert the bulb and socket into the rear of the taillight assembly and turn the socket clockwise to lock it in place. Slide the taillight assembly back into the truck, aligning the pins on the housing with the body.
Step 6
Insert the two mounting screws and tighten them with a Phillips-head screwdriver. Do not over-tighten the screws or you will crack the plastic taillight assembly.
Step 7
Close the tailgate and turn the lights on to verify that the taillights are working properly.