Conditions for Setting the DTC
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2002 GMC Yukon XL, 2002 GMC Yukon, 2002 Chevrolet Tahoe, 2002 Chevrolet Suburban, and 2002 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
If the transponder value from the ignition key does not match the one stored in memory, the theft deterrent control module sets this DTC. This DTC indicates the use of a key with a transponder value that has not been learned by the theft deterrent control module. The vehicle theft deterrent (VTD) system considers this to be a theft attempt.