NTHSA opens safety probe of Chevy Volt

DETROIT – Federal safety regulators are launching a safety defect investigation of the Chevrolet Volt following a recent test that resulted in a fire in the battery pack.

The National Highway Traffic Safety Administration began looking more closely at the risk after a case from last May when a Volt caught fire about three weeks after undergoing a side-impact crash test in Wisconsin. In that incident, the car’s lithium-ion battery was not drained after the crash, a safety procedure regulators did not follow.

In an effort to re-create the May test, NHTSA conducted three tests last week in which the battery packs were intentionally damaged to the point where the vehicle’s coolant line ruptured.

A test conducted Nov. 16 did not result in a fire. A temporary increase in temperature was recorded in a test conducted Nov. 17. In the third test, on Nov. 18, the battery pack began to smoke and emit sparks.

On Thursday, the battery pack tested on Nov. 17 caught fire. In all three tests, NHTSA officials rotated the battery pack within hours after it was damaged.

“While it is too soon to tell whether the investigation will lead to a recall of any vehicles or parts, if NHTSA identifies an unreasonable risk to safety, the agency will take immediate action to notify consumers and ensure that (General Motors) communicates with current vehicle owners,” NHTSA said in a statement released Friday. “Chevy Volt owners whose vehicles have not been in a serious crash do not have reason for concern.”

General Motors Co. reiterated that message.

“The Volt is safe and does not present undue risk as part of normal operation or immediately after a severe crash,” the automaker said in a statement.