I'm in the process of selling the 2003 Prius with the failed transaxle. Long ago, I purchased a Memoscan OBDII reader for the 2003, which gave me the capability of reading/clearing basic codes. It worked well and paid for itself. Can the OBDII reader be used with a 2010? I think maybe no. If not, I'll throw it in with the 2003. At second fill up, 53.1 MPG. Awesome. No problems, creaks, noises (except for the inverter whine). Am in process of removing blue background behind emblems (looks bad with red car) and replacing with carbonfiber vinyl film.
My OBDII device works with my 2010 Prius. From what I understand, it will read the basic OBD codes but not the Toyota specific codes.
Toyota uses both ISO14230 (KWP) and ISO15765 (CAN) protocols over the OBD2 port. I think the GEN1 only has the ISO14230, while GEN2 & GEN3 have a mix of the two. The clear path is that everything will be CAN in the future. So it's not clear exactly which functions the older scanner supports. It has to support KWP, and may support CAN. Since some devices are still on the KWP bus even in the 2010, even a KWP-only scantool may be useful on later model vehicles. So the answer is a big maybe, depends, who knows? About the only practical way to answer the question is to plug the old scanner into a newer car and see if it shows anything.
