Software glitch stalls Toyota's hybrid

Toyota is asking 75,000 owners of Prius hybrid cars to come in and have their vehicle's software checked.

A software glitch in some 2004 and 2005 Priuses can make a warning light come on without cause, and in some cases shut down the gas engine altogether, a Toyota spokeswoman said. Because the Prius also has an electric engine, drivers typically can safely get to the side of the road, where they can restart their cars.

Sixty-eight incidents of Prius warning lights flashing without cause or engines shutting down have been reported to the National Highway Traffic Safety Administration (NHTSA), the Toyota spokeswoman added. NHTSA has not asked for a recall but has told Toyota to notify owners. The automaker is doing that through letters.

When drivers bring in their cars, mechanics will examine the car and reprogram the electronic control module if necessary. In some cases, mechanics may also apply a dielectric grease to a connector on the transaxlen - a unit that combines a transmission and an axle's differential gear - to keep water from getting inside. Water entering the transaxle can cause problems to those related to the software glitch.

While vapour locks, worn clutches and bad tires have long stalled drivers, motorists are discovering a whole new generation of problems with the advent of the electronic car. Manufacturers have replaced traditional emergency brakes and other parts with electronic devices in many models in the past few years.

In the relatively near future, radar systems to give drivers a better view of surrounding traffic, as well as other safety devices, will appear. By 2040, cars could even drive themselves, some experts have speculated.

New types of energy-efficient engines monitored by microprocessors will also come out.

The public, though, will have to be convinced of the reliability of these electronic wonders, and the current problems with the Prius (not to mention the general public's familiarity with desktop crashes) are not likely to help.

Despite a few minor problems, the Prius has become quite a strong seller for Toyota. The company shipped 125,742 of the hybrid vehicles worldwide in 2004, selling 53,991 in the US alone. So far, 81,042 have been sold in the US in 2005.

Michael Kanellos writes for CNET News.com