One problem related to software has been reported for the 2007 Toyota Prius. The most recently reported issues are listed below.
Vehicle does not achieve advertised fuel consumption performance. I have complained about this since the first service visit. Today a factory technician got unachievable results suggesting that our real world experience after 29,000 miles with the vehicle is normal. He claimed to have gotten 66. 984 mpg after a 42. 2 miles of 55 mph highway and "in town" driving, noting only that an out of fuel fault had never been cleared.