09/19/2015 02:27 EDT | Updated 09/19/2015 02:59 EDT

U.S. Could Fine Volkswagen Up To $18 Billion Over Alleged Falsified Emissions Results

Automaker Volkswagen could face up to $18 billion U.S. in fines for allegedly using software that falsifies emissions data.

The Environmental Protection Agency has ordered the automaker to fix 500,000 VW and Audi cars it says have a device that detects when an emissions test is being done. The car’s emissions control systems are only fully turned on when an emissions test is being carried out, the EPA says.

The agency says VW faces a $37,500 fine per vehicle, which could amount to more than $18 billion.

The affected car models are the 2009 to 2015 VW Golf, Jetta and Beetle, as well as the 2009 to 2015 Audi A3 and the 2014 and 2015 VW Passat.