By James R. Hood

When the National Highway Traffic Safety Administration (NHTSA) announced earlier this week that it was opening a preliminary evaluation into battery fires in the $90,000 battery-powered Tesla S luxury car, It got a yawn from experienced safety advocates and reporters who routinely cover the NHTSA beat. It is, after all, what safety agencies do — investigate safety issues.

By Jerry Hirsch
Federal safety regulators opened a probe into a series of fires in Tesla Motors Inc. electric cars following crashes.

The National Highway Traffic Safety Administration said Tuesday that it would investigate why two of the expensive Tesla Model S sporty hatchbacks have caught fire this year following accidents in which the battery casing that serves as the undercarriage of the car cracked open.

A third fire, which took place in Mexico, won’t be part of the investigation because it is outside the agency’s jurisdiction.

by Bill Vlasic and Jaclyn Trop

DETROIT — A federal safety investigation of the Tesla Motors electric Model S sedan announced on Tuesday comes at a critical juncture for the car and the company.

For the first time, regulators are examining whether the design of the high-end vehicle and its advanced lithium-ion battery pack are defective and the cause of two battery fires.

As federal investigators announced a formal safety probe Tuesday, fledgling electric car maker Tesla Motors is getting a quick lesson in what it’s like to be treated like a big, mainstream automaker.