Thought it was a one off, but it appears I'm not alone: http://www.mykonaev.com/forum/viewtopic.php?p=295#p295 Anybody else had this issue?
It reminds me of the old joke about Bill Gates riding with a group of experts when the car stalls. Everyone suggests a different solution until finally Bill says, "Let's all get out of the car and back in again." These are good old-fashioned software crashes. I'm actually surprised that modern cars don't come with reset switches. In the meantime, disconnecting the small battery should cure anything that doesn't involve a hardware fault.