Toyota Motor Corp. will develop a high-tech system that not only prevents intoxicated motorists from starting their cars, but also stops the vehicles if signs of drunken driving are detected, sources said.

The system will monitor erratic driving, analyze blood-alcohol levels through the driver's sweat, and check the eyes of the person behind the wheel.

The world's No. 2 automaker intends to commercialize the system as early as 2009.

Toyota has trailed U.S. and European automakers in preventing their vehicles from operating if the driver is drunk.

In the United States and some EU countries, vehicles equipped with a breath alcohol ignition interlock device (BIID) require the driver to provide a breath sample. If the BIID detects a blood-alcohol concentration higher than permitted, the vehicle will not start.

But critics have argued that the BIID's effectiveness is limited because a drunken driver might simply get somebody else to breathe into the device. The BIID does not check the condition of the driver when the vehicle is in motion.

Toyota's device will examine the driver in two stages: before starting a car and while driving.

When a driver gets into a car and holds the steering wheel, a sensor will measure the blood-alcohol level through sweat and other signs of the driver's palms. If the result exceeds a certain limit, the car will not start.

If the driver clears that hurdle and starts the car, a camera in the system will check the driver's eyes to see if they are focused. It will also check for unusual steering.

If there are signs that the driver is under the influence, the car will automatically slow down and stop.

Toyota will initially offer the system as an option because it is expected to be expensive. But the automaker plans to roll out cars equipped with the system as a standard feature if it can cut production costs.

Toyota's flagship Lexus LS model already is equipped with a radar-camera system that sounds an alarm if it detects pedestrians, other vehicles and obstacles at times when the driver might not be focused on the road.

The automaker believes its anti-drunken driving system will further heighten global competition in producing such features, the sources said.

Japanese carmakers have accelerated development of systems to prevent drunken driving since a drunken city employee caused a traffic accident on a bridge that killed three children in Fukuoka in August.(IHT/Asahi: January 4,2007)