One problem related to automatic transmission cooler has been reported for the 2005 Toyota Prius. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2005 Toyota Prius based on all problems reported for the 2005 Prius.
2005 Toyota Prius stalled on an overpass with no shoulders. The transmission became stuck in park, and the vehicle could not be pushed since the front wheels were locked up. The car was eventually towed, and it had to be dragged onto the flatbed wrecker since the front wheels would not roll. The problem was determined to be a failed pump for cooling the inverter. The pump failed such that it blew a fuse that also controlled the transmission shifter, preventing the car from being put into neutral so that it could be pushed out of traffic lanes. This is a very unsafe failure mode.