Japanese authorities have ordered Toyota to investigate the brakes in the Prius.
Japan Tells Toyota to Test Prius Brakes for Defect - NYTimes.com
NAGOYA, Japan — The Japanese government said Wednesday that it had ordered Toyota to investigate a possible defect in its newest Prius hybrid model after receiving 14 reports of brake trouble, another blow for an automaker already embroiled in its biggest-ever recall.Complaints mount about Prius brakes - Feb. 3, 2010
In the U.S., more than 100 complaints alleging poor brake performance have been lodged with the National Highway Traffic Safety Administration against the 2010 Prius, a newly designed version of the car that was introduced last summer.This is really bad news for Toyota and their signature hybrid. While Prius sales were up in January compared to last January, this sort of news is going to scare off anyone who thinks the current massive Toyota recalls don't affect hybrids.
BTW, I've seen reports about this issue before. According to an NHTSA memo the regenerative brakes cut out for a moment prior to the friction brakes kicking back in. That momentary changeover makes it seem like you're accelerating, although it's technically just not slowing down any more. Either way, that's a scary thought when you're applying the brakes.
UPDATE: Notice from Toyota
In certain 2010 model year Prius vehicles, Toyota has received reports that some customers have experienced inconsistent brake feel when the vehicle is driven over potholes, bumps or slippery road surfaces.Not exactly alot of information in their statement, but a statement indicates they are aware of the issue.
Toyota is currently in the process of confirming these reports and investigating the vehicle driving conditions under which the reported phenomenon occurs. It would be premature to comment until the investigation has been completed.