GM ignition switches
A recalled Chevy Cobalt ignition switch is seen at Raymond Chevrolet in Antioch, Ill., July 17. Reuters/John Gress

People who own General Motors Co. (NYSE:GM) cars are supposed to be able to see whether their vehicles are being recalled by punching their vehicle identification numbers into a text box on a website. But a federal regulator said the system doesn’t work. The National Highway Traffic Safety Administration said it has “determined that owners of some recalled GM vehicles are receiving incorrect and misleading results” when they enter their VINs.

“Consumers who have used GM’s tool and found no recall should recheck,” NHTSA said, adding it had instructed GM to fix the problem and notify owners.

GM representative Greg Martin told USA Today late Friday it was making the necessary changes.

NHTSA said U.S. Sen. Barbara Boxer, D-Calif., had notified it about the issue. She had been particularly hard on GM CEO Mary Barra during Senate hearings on why the company was so slow to act on a potentially fatal flaw in its ignition switches dating back to 2001. A faulty switch can fall out of the run position, killing the engine along with the power steering and brakes. Thirteen deaths have been linked to the problem.

Hundreds of claims are expected to be filed for compensation related to the switch problem. Reuters reported a compensation fund will be administered by Kenneth Feinberg, a Washington lawyer who has run other high-profile funds, including the one created after the BP PLC (NYSE:BP) oil spill in the Gulf of Mexico in 2010.