Invalidate All

This procedure will erase all key fobs from memory.

Install a scan tool.
Turn ON the ignition with the engine OFF.
With the scan tool, select Body and Accessories.
Select Keyless Entry.
Select Module Setup.
Select BCM.
Select Program Key Fobs.
Select Invalidate All.
Follow the scan tool on screen instructions.
Remove the scan tool.
Exit the vehicle. Operate all functions on transmitters to verify correct system operation.