sounds like a computer problem. basically its having a sensor tell it something thats completely out of the parameters and it doesnt make sense to the computer.
On a more serious note... clear the code then run it then scan it and if you get more different codes... it's the ecm... I've had some of those pop up and that was the outcome... not 100% on your situation but with the few of mine that was the problem...
BTW I love that code... rationality error... good stuff.
The problem was dumb. The VSS went bad, and the computer thought the ratio for 1st gear got changed somehow.... It eventually threw that code "First Gear Ratio Incorrect". The guy who owned the car kinda looked at me, and says "Can that just happen while I am driving?"