How do you program the remote key fob on a 2005 Chevy Colorado?

To program a remote key fob for a 2005 Chevy Colorado, first, sit in the vehicle with all doors closed. Insert the key into the ignition and turn it to the "On" position without starting the engine, then press the "Unlock" button on the driver's door. Next, turn the ignition off and remove the key, then press and hold the lock and unlock buttons on the fob simultaneously for about 15 seconds. Finally, turn the ignition back to "On," and the fob should be programmed; test it by locking and unlocking the doors.