1999 GMC Sierra 1500 Remote Programming

 Note: All existing GM transmitters will need to be reprogrammed during this procedure                                                       M

1. Close all vehicle doors.
2. Insert key into ignition
3. Hold down the UNLOCK button on the driver side door panel. Continue to hold down until instructed to release in step 9.
4. Perform steps 5 through 8 in fairly rapid succession.
5. Turn the ignition switch to the ON position (do not crank the engine)
6. Turn the ignition switch to the OFF position.
7. Turn the ignition switch to the ON position (do not crank the engine).
8. Turn the ignition switch to the OFF position.
9. Release the unlock button on the door panel. The vehicle should lock and unlock the doors automatically.
10. Hold down the LOCK and UNLOCK buttons on the transmitter simultaneously until the doors lock and unlock to confirm programming. –  (You may need to hold LOCK & UNLOCK for up to 30 seconds.)
11. Repeat step 10 for each additional transmitter (including any preexisting transmitters).
12. Turn the ignition switch to the ON position to exit the transmitter programming mode.