It seems like everyone wants to know the question, "what happens when a hybrid runs out of gas?" so I wasn't surprised to find several personal anecdotes on the internet. Some tell tales that you can run the car on battery power and coast into the gas station on fumes, but this doesn't seem to be the norm. I read somewhere that this is a safety feature, designed to keep you from destroying the car by running it into the ground on the electric engine/battery alone. I also read that if you manage to keep the car running and fill the tank, then reboot, the warning lights should go away after 50 miles. Or just don't let it get that low. Especially not on a Sunday afternoon.