Hacking my Toyota Prius – Fun with OBDII

Toyota did not intend for Prius owners to perform maintenance on their own vehicle. Without a tool that can send commands to the car’s ECU/computer, standard maintenance such as changing brakes, flushing the radiator, or changing the transmission fluid cannot be done properly. As I perform my own maintenance on my car, I became interested in OBDII (On Board Diagnostics) tools and researched the difference between dealer and consumer OBDII tools. Consumer OBDII tools such as the Scanguage2 and ELM327 can only pull diagnostic codes and read data from the ECU while Dealer tools can issue commands to the ECU and even reprogram the ECU. Definately dangerous if you have no idea what you’re doing 🙂

In the video, I’m toggling my on/off the power indicator light (see top left) using Toyota Techstream TIS (dealer/mechanic software), Drew Technologies Mongoose OBDII cable, Windows XP (32-bit) virtualized on my Mac.

Gallery of Prius in Maintenance Mode and various OBDII tools