Toyota Motor Corp. is considering recalling its latest Prius hybrid sedan in Japan and the U.S. as investigations begin over potentially faulty brakes. Yesterday the company announced the problem is due to a software glitch and said it began loading updated software into new vehicles produced beginning late last month.

But Toyota did not notify customers about the problem. The company said yesterday the system falls within legal guidelines and is not considered a safety problem.

There have been more than 160 reports of erratic brake behavior in the hybrid model, primarily on slippery or bumpy roads, in Japan and the U.S. In certain cases, Toyota acknowledges there can a lag of about one second when the car shifts from regenerative braking to the antilock braking system. At highway speeds, the delay could extend braking distance by as much as 90 ft.

The U.S. National Highway Traffic Safety Administration opened an investigation yesterday. Earlier in the week, Japan’s Ministry of Transportation ordered Toyota to investigate the problem.

Toyota also is evaluating whether the Sai and Lexus HS250h hybrids, which use the same braking system, also are affected.

If Toyota moves ahead with the Prius recall, it would be the company’s third major campaign in the last few months. Since last fall, Toyota has recalled more than 8 million vehicles worldwide to fix problems involving the floor mat and accelerator mechanism, both of which can cause the throttle to remain open longer than the driver intends.

Prius models from the 2004-2009 models year are involved in the floor mat recall. NHTSA has received more than 100 complaints about so-called unintended acceleration in 2004-2009 Prius cars.

The U.S. National Aeronautics and Space Administration is partnering with General Motors Co. to develop next-generation robots that they hope to eventually deploy in automotive and aerospace industries. About a half dozen GM engineers currently are working with NASA counterparts with help from Oceaneering Space Systems at the latter’s Johnson Space Center in Houston as part of a five-year collaboration that began in 2007.

Robonaut 2

Thus far, the partners have updated NASA’s 10-year-old Robonaut humanoid robot that was designed for space travel. They say the new Robonaut 2 (R2) is faster, more dexterous—including being able to use its hands to perform functions not possible with current robots—and otherwise more technologically advanced than its predecessor.

Using leading-edge control, sensor and vision technologies, similar robots could eventually assist astronauts during hazardous space missions and help GM build new vehicles, working in tandem with people.

GM has no immediate plans to deploy R2 robots in plants. But the company says it is actively looking for ways to utilize some of the technology in plants. It also expects the advancements in controls, sensors and vision technology to led to improvements in vehicle safety systems.

NASA and GM have a long history of partnering on technologies, starting in the 1960s with the development of the navigation systems for the Apollo space missions. GM also contributed to the development of the Lunar Rover Vehicle, the first vehicle to be used on the moon.

The U.S. Army will not renew its contract to purchase Humvee military vehicles from AM General Corp. when supplier’s contract expires in November. The decision was revealed in the Dept. of Defense’s latest budget, which was announced earlier this week.

Mishawaka, Ind.-based AM General, which sold its non-military Hummer brand to General Motors Corp. in 1999, has provided even more rugged Humvee models to the army for 25 years. But the Army says the SUVs don’t provide the necessary protection against the latest-generation of road-side bombs and improvised explosive devices being used against U.S. troops in Afghanistan and Iraq.

Several other companies, which have developed new models with special reinforced underfloors, are vying for the Army contract. AM General still has about 2,600 Humvees on order from the Army that it plans to complete by October. Although it has contracts with other branches of the U.S. military and with other countries, the Army constitutes more than 80% of the company’s business.

In addition to the Humvee, AM General produces the Hummer H2 on a contract basis for GM. Last summer, GM inked a preliminary deal to sell Hummer to China’s Sichuan Tengzhong Heavy Industrial Machinery Corp. The deadline for the sale, which has met some opposition in China, has been extended until the end of the month.

Chrysler Group LLC has extended its contract with Cummins Inc., which supplies the 6.7-liter 6-cylinder diesel engine for Ram heavy-duty pickup trucks. The new agreement is described as a multi-year deal.

Cummins says it has built 1.7 million engines for Chrysler since 1989. Four in five buyers of Ram heavy-duty pickups currently opt for the Cummins diesel, which makes 350 hp and 650 lb-ft of torque. The powerplant is 90% cleaner than the original 5.9-liter mill Cummins supplied to Chrysler. That powerplant generated 160-hp and 400 lb-ft of torque.

Tata Motors Ltd.’s Jaguar arm will field a car in this year’s 24-hour Le Mans endurance race. Drivers Scott Pruett and Marc Goossens will pilot a XKR GT2 for Michigan-based JaguarRSR in the race’s GT2 class. Modifications to the car will include boosting output of the supercharged 5.0-liter V-8 engine 10% to 550 hp.

Jaguar has won at Le Mans seven times, which ranks fourth best all-time. It took the checker flag with the C-type in 1951 and 1953, while the D-type notched consecutive victories in 1955, 1956 and 1957. More recent successes include a first-place finish for the V-12-powered XJR-9LM in the C car class and an outright victory in 1990 with the XJR-12.

Jaguar, which is celebrating its 75th anniversary this year, has been conspicuously absent from motorsports in recent years, save for a less-than-spectacular run in Formula One last decade. JaguarRSR team boss Paul Gentilozzi also will campaign the XKR in this season’s American Le Mans Series.