Federal Safety Regulators Ramp Up Tests on Chevrolet Volt

Just the Facts:

• Federal safety regulators are looking into how test crashes on the Chevrolet Volt affect welded material as they continue to investigate post-crash fires in the plug-in hybrid.
• The National Highway Traffic Safety Administration says it has five Volts at its Vehicle Research and Test Center in Ohio and that it is studying possible damage to the battery tunnel on the driver and passenger sides of the vehicles.
• NHTSA is searching for a possible defect that might cause the Volt's battery to catch fire after a crash.

WASHINGTON — Federal safety regulators are looking into how test crashes on the Chevrolet Volt affect welded material as they continue to investigate post-crash fires in the plug-in hybrid.

The National Highway Traffic Safety Administration says it has five Volts at its Vehicle Research and Test Center in Ohio and that it is studying possible damage to the battery tunnel on the driver and passenger sides of the vehicles.

"The objectives of this test program are to document if any changes in the welding process are visible at the area of intrusion," said a memorandum posted December 6 on the NHTSA Web site. "Any additional objectives will be discussed and agreed on an ongoing basis."

Federal safety regulators are inspecting and evaluating possible damage to the battery tunnel on the driver and passenger sides of the Volts, the memo said.

The memo offers a more detailed look at how NHTSA, along with General Motors engineers, is honing in on a possible defect that might cause the Volt's battery to catch fire after a crash.

NHTSA opened a defect investigation into an estimated 5,000 2011-'12 Volts on November 25 after a Volt caught fire three weeks after the agency finished side-impact testing on the vehicle. "Intrusion in a crash may damage the battery, which may result in a substantial thermal reaction and fire," according to NHTSA's "problem description" posted on its Web site.

The federal safety agency said the investigation into the Volt is part of its "ongoing review of the emerging technology involved in electric vehicles." Such an investigation could lead to a recall.

There have been no reports of real-world fires involving the Volt.

Inside Line says: NHTSA takes the unusual step of detailing its detective work as it continues to investigate the Chevrolet Volt.