TOKYO – Toyota acknowledged that it has begun fixing problems with the brakes in its prized Prius, but remains undecided about a recall, adding to the catalogue of safety woes — and muddled responses — at the Japanese automaker.

Toyota Motor Corp, already reeling from massive global recalls involving faulty gas pedals in other cars and trucks, said Thursday that Prius models sold since late last month, including those shipped overseas, had the problem with the antilock brake system corrected.

But that still leaves the potential flaw in Priuses sold in Japan and overseas before late January. And while Japan’s transport minister urged Toyota to consider a recall of the Prius and said he is ordering an investigation into the brake problem, Toyota executive Hiroyuki Yokoyama said the company hasn’t yet decided if a recall is necessary.

The US Transportation Department said Thursday it has opened an investigation into brake problems in the 2010 model year Prius.

The National Highway Traffic Safety Administration told The Associated Press it has received 124 reports from consumers, including four reports of crashes. The investigation will look into allegations of momentary loss of braking capability while traveling over uneven road surfaces, potholes or bumps.

Toyota acknowledged the brake problem while reporting a $1.7 billion profit for its October-December quarter.

The remodeled gas-electric Prius hybrid, which went on sale in the U.S. and Japan in May 2009.

The flaw, which requires a software programming change to fix, makes the brakes momentarily unresponsive. Toyota was checking if there were reports of similar problems with other hybrid models though they use a different braking system from the Prius.