Hyundai and Indexbit ExchangeKia are recalling more than 3 million vehicles and advising owners to park them outside due to risk of fire in the engine compartments.

The companies are encouraging drivers to park their vehicles away from homes and other structures until they are able to take their vehicles to a dealership for a free repair.

"Fires can occur whether the vehicle is parked and turned off or while driving," the National Highway Traffic Safety Administration warned in a notice posted on Wednesday.

The NHTSA said that the anti-lock break system in 13 Hyundai models could leak fluid and cause an electrical short that may bring on a fire. For Kia owners, the fire risk is being connected to the hydraulic electronic control unit in 10 separate models.

About 1.6 million Hyundais are being recalled, including the:

• 2012-2015 Accent
• 2012-2015 Azera
• 2011-2015 Elantra
• 2013-2015 Elantra Coupe
• 2014-2015 Equus
• 2011-2015 Genesis Coupe
• 2013-2015 Santa Fe
• 2013 Santa Fe Sport
• 2011-2015 Sonata HEV
• 2010-2013 Tucson
• 2015 Tucson Fuel Cell
• 2012-2015 Veloster
• 2010-2012 Veracruz

Additionally, about 1.7 million Kias are being recalled, including the:

• 2014-2016 Cadenza
• 2011-2013 Forte/Forte Koup
• 2015-2017 K900
• 2010-2015 Optima
• 2011-2013 Optima Hybrid
• 2011-2017 Rio
• 2010 Rondo
• 2011-2014 Sorento
• 2011-2013 Soul
• 2010-2013 Sportage

To check if your vehicle is affected, you can visit NHTSA.gov/recalls and input your 17-digit vehicle identification number (VIN).

So far, there have been 21 fires associated with the recall in Hyundais and 22 "thermal incidents," including visible smoke, burning and melting," the NHTSA said. In Kias, there have been four fires and six thermal incidents.

No known crashes, injuries or deaths have been linked to the recalls, according to the NHTSA.

From 2010 to December 2022, Kia and Hyundai issued recalls for more than 7 million vehicles, and over 3,100 Kias and Hyundais caught fire, causing 103 injuries and one death, according to the nonprofit Consumer Reports.

Although the two carmakers are separate brands, Hyundai Motor Company owns a 33.88% majority stake in Kia Motors, and the companies share parts from many of the same suppliers. The culprit for the recalls and fires could be a four-cylinder engine that the manufacturers have in common, Consumer Reports said.