1999 Tahoe 80K miles. Been there! After parking at the Olympic Peninsula Mt. Constitution parking lot. Put the key in and tried to start. The result was an alarm and no start. Ended up towing the truck down the mountain a couple miles and the truck started no problem. The cause was the frequencies transmitted from the park tower shut down the theft system!
Apparently no shielding is provided with the system. More of the exciting saga is available.