May 18, 2005
Toyota Motor Corp is focusing efforts on a software problem in the popular hybrid Prius automobile after complaints that the gas-electric hybrid cars stall or shut down without warning while driving at highway speeds.
The complaints include 2004 and some 2005 model year cars. The National Highway Traffic Safety Administration has received 13 reports of the engine shutdowns and some vehicle-information sites have posted complaints about the problem.
Some of the malfunctioning Prius cars had to be towed to the shop before they could be restarted. Toyota blames the problem on a software glitch in the sophisticated Prius computer system.
The car has both a gasoline engine and an electric motor, which is set to provide it with power during certain driving conditions, particularly in city driving. The gasoline engine is supposed to be shut down or run at a very low level when the car is driving slowly or idling but provide most of the car's power when it is cruising at highway speeds.
There are no injuries or fatalities associated with the problem. A NHTSA spokesman said the agency is monitoring the complaints, but no formal investigation has been initiated.
Toyota identified a "programming error" in the computer systems of 23,900 Prius cars last year and sent owners a service notice advising them to bring the cars into dealers for an hour-long software upgrade.
