<h1>2021 GMC Sierra – Smart Key Remote Programming Instructions</h1> <p><font size="3">The 2021 Sierra uses the same smart key system as the 2020 model. Follow the method that applies based on whether you have working fobs available. </font></p> <p><font size="3"><b>With Two Working Transmitters</b> </font></p> <ul> <li><font size="3">Step 1: Take out the key blade from one functioning transmitter. </font></li> <li><font size="3">Step 2: Put both working remotes inside the cabin. </font></li> <li><font size="3">Step 3: Use the key blade to turn the driver door lock counterclockwise five times within 10 seconds. The system will display “READY FOR REMOTE #2, 3, 4, ETC.” </font></li> <li><font size="3">Step 4: Open the center console, remove the tray, and place the new remote in the pocket near the front edge.</font></li> <li><font size="3"> Step 5: Press the ENGINE START/STOP button. When successful, the display will confirm the remote is programmed. </font></li> <li><font size="3">Step 6: Take out the remote and press LOCK or UNLOCK. </font></li> <li><font size="3">Step 7: Add more remotes by repeating the process. </font></li> <li><font size="3">Step 8: Finish by pressing and holding ENGINE START/STOP for 12 seconds. </font></li> </ul> <p><font size="3"><b>Without Recognized Remotes If no existing fobs are available, use the following method:</b> </font></p> <ul> <li><font size="3">Step 1: Remove the key from the new remote. </font></li> <li><font size="3">Step 2: Turn the key in the door lock to the unlock position five times quickly. The message “REMOTE LEARN PENDING, PLEASE WAIT” will appear. </font></li> <li><font size="3">Step 3: After 10 minutes, the display will read “PRESS ENGINE START BUTTON TO LEARN.” Press the button. </font></li> <li><font size="3">Step 4: Repeat the previous step twice more (three cycles total). After the third cycle, old remotes will be erased, and the vehicle will display “READY FOR REMOTE #1.”</font></li> <li><font size="3"> Step 5: Insert the new remote in the console slot. </font></li> <li><font size="3">Step 6: Press ENGINE START/STOP once to learn the remote. </font></li> <li><font size="3">Step 7: Remove the fob and press LOCK or UNLOCK to confirm. </font></li> <li><font size="3">Step 8: Add any remaining remotes by repeating the same steps. </font></li> <li><font size="3">Step 9: Press and hold the ENGINE START/STOP button for 12 seconds to close programming mode. </font></li> <li><font size="3">Step 10: Return the key blade to each remote.</font></li> </ul>
