<h1>2003 GMC Sonoma – Keyless Entry Remote Fob Programming Instructions</h1> <p><font size="3"> If you need to add or replace remote fobs for your 2003 GMC Sonoma, follow this step-by-step guide carefully. This process allows you to program multiple remotes during a single session. Before You Begin Make sure all vehicle doors are completely shut. Have all remote transmitters you want to program ready—any remotes not reprogrammed now will stop working. You will need the vehicle’s ignition key. </font></p> <p><font size="3"><b>Programming Process</b> </font></p> <ul> <li><font size="3">Step 1: Close all the doors to ensure proper entry into programming mode.</font></li> <li><font size="3"> Step 2: Insert your key into the ignition, but don’t turn it yet. </font></li> <li><font size="3">Step 3: Press and hold the power UNLOCK button on the driver’s door. Keep holding this button until step 9. </font></li> <li><font size="3">Step 4 – 7: While still pressing the unlock button, quickly perform the following sequence: Turn the ignition to the ON position (do not start the engine), Turn it to OFF, Back to ON again, Then back to OFF. Be sure to perform this sequence quickly and steadily to enter programming mode. </font></li> <li><font size="3">Step 8: Now release the UNLOCK button. If done correctly, the door locks will automatically cycle—locking and unlocking once. This confirms you've entered programming mode. If you don’t see the door locks respond, remove the key, open the driver’s door fully, and start again from Step 1. </font></li> <li><font size="3">Step 9: On the first remote, press and hold both the LOCK and UNLOCK buttons at the same time. Continue holding for up to 30 seconds until the doors lock and unlock again. This confirms the remote has been successfully programmed. </font></li> <li><font size="3">Step 10: Repeat Step 9 for each additional remote. Be sure to do this before exiting programming mode, or those remotes will not function. </font></li> <li><font size="3">Step 11: Turn the ignition switch to the ON position once more to exit programming mode. </font></li> <li><font size="3">Step 12: Remove the key from the ignition. </font></li> <li><font size="3">Step 13: Test each remote to ensure all programmed remotes can lock and unlock the vehicle.</font></li> </ul>
