From AB
Toyota engineers have worked hard to get the emissions that come out of the tailpipe of the Prius V down to a low level, but that doesn't mean everything is copacetic with the car's exhaust system. To fix a known problem, Toyota has announced a service campaign for the Prius V, both in the U.S. and Japan.
It is reported that the problem is with "weak actuators-control mechanisms" in the exhaust-heat-recovery systems that can end up leaking engine coolant, which will then force the car into a "safe" mode. Some second-gen, 2004-07 standard Prius models were affected by a similar problem in the past.
The new issue affects about 8,000 vehicles in Japan and 20,000 in North America. Prius V owners will get the problem fixed at no cost to owner.