I was getting this code and it was a non specific communication problem. Coupled with some other odd issues the dealer felt it was aproblem with the ignition switch. They installed a new one? Looking at the chrome bezel that the key goes into it looks old with the 1000 scratches from missing the hole. I thought the switch was all one piece with the chrome outer bezel. Also, no new key? Should it need a new key? Did they really change it? No more engine light yet.

 

They can change out the mechanism without changing out the tumblers or casting (just the guts).