The Chevrolet Volt has been under investigation for a while now after several of the vehicles caught fire after crash testing. GM has since offered to buy the Volts back from concerned drivers and the issue has hurt sales of the vehicle that were already slow. The NHTSA is now zeroing in on a possible cause for the fires after the crash tests.
The WSJ reports that the NHTSA has asked its testing centers to examine welded components under the car that are near the battery pack. Specifically the NHTSA calls for photos of the "floorplan/crossmember near the battery tunnel." The WSJ reports that the engineers at GM working on the issue think that they can apply a fix to cars in the field once the issue is pinpointed without having to do major recalls.
According to GM, the cause for the fires is cooling lines that were damaged in the side impact tests. Once that coolant line breaks the coolant drips out onto wiring near the battery. Once that coolant crystallizes, it causes a short in the wires and at times leads to a fire. I have to wonder though how that explanation would cover the Volt that sparked and smoked immediately after the accident when it wouldn’t have had time to crystallize.