How to Replace the Rear Signal Lights in a GMC Sierra
- 1). Set your Sierra's parking brake and remove the keys out of the ignition before starting.
- 2). Walk to the back of your truck and lower the tailgate.
- 3). Remove the two screws from the side of the taillight assembly. Put the screws in your pocket or in a small bag so you can find them later.
- 4). Disengage the taillight assembly from the truck by pulling it rearward.
- 5). Press the bulb socket release tab, and twist the socket counterclockwise to remove it from the taillight assembly.
- 6). Lift the old bulb straight out of the socket and replace it with the new one. Then, twist the bulb socket back into the taillight assembly until it clicks.
- 7). Activate your Sierra's new turn signal. If it lights up, screw the assembly back into place and close the tailgate.
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