Toyota: Software to Blame for Prius Brake Problems

Via CNN -

Without issuing a recall of its iconic Prius hybrid vehicles, Toyota said Thursday a software glitch is to blame for braking problems in the 2010 model.

"We would want to be given a little time," Hiro Yuki Yokoyama, Toyota's managing officer, said when reporters asked whether a recall was in the works.

The company changed its braking system software in January as part of what it called "constant quality improvements," but did not say what it would do about vehicles manufactured before then.

Toyota officials described the problem as a "disconnect" in the vehicle's complex anti-lock brake system (ABS) that causes less than a one-second lag. With the delay, a vehicle going 60 mph will have traveled nearly another 90 feet before the brakes begin to take hold.

Brakes in hybrids such as the Prius operate differently from brakes in most cars. In addition to standard brakes, which use friction from pads pressed against drums or rotors, the electric motors in hybrids help slow them. The process also generates electricity to recharge the batteries.

The Japanese government has warned Toyota to take seriously mounting complaints of brake problems with its 2010 Prius hybrid.

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"The complaints received via our dealers center around when drivers are on a bumpy road or frozen surface," said Paul Nolasco, a Toyota Motor Corp. spokesman in Japan. "The driver steps on the brake and they do not get as full of a braking feel as expected."

In the United States, 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.

"NHTSA has received a number of complaints about a potential defect affecting the brake system in Toyota's Prius hybrid and is conducting field work to examine the issue," the agency said Wednesday.

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"I have been driving my 2010 Prius for 6 months and have experienced the following nearly 10 times," one owner wrote. "When braking, if a pothole or bump in the road is hit, the car seemingly jerks forward/accelerates for a split second."

The Prius is Toyota's third best-selling model in the United States, ranking behind the Camry mid-size sedan and the Corolla compact car.