2021 Ford Expedition and Lincoln Navigator owners are being asked to park their vehicles outside and away from buildings after a series of fires.

16 incidents have already been reported and 12 of them have reportedly occurred while the vehicle was parked with the ignition turned off. This is alarming as these are the same conditions that would occur if the vehicle was parked in your garage overnight.

Given the seriousness of the issue, Ford is recalling 39,013 vehicles in the United States built between December 1st, 2020 and April 30th, 2021. The automaker isn’t waiting to alert owners as they’re treating the fire risk with a “high sense of urgency” and will notify them quickly via the FordPass and Lincoln Way apps as well as traditional snail mail.

Also Read: 2022 Lincoln Navigator Boasts A Bigger Grille, Hands-Free ActiveGlide Semi-Autonomous Driving System

Ford began investigating the issue on March 24th, but has yet to determine a cause. However, the company believes the problem originates in the “rear of the engine compartment near the passenger side of the vehicle.”

While the automaker isn’t sure what is causing the fires, Ford Passenger Vehicles General Manager Jeffrey Marentic said, “We are working around-the-clock to determine the root cause of this issue and subsequent remedy so that customers can continue to enjoy using their vehicles.” He added, “We recognize the importance of staying in touch with our customers until we resolve this matter.”

Three fires have reportedly occurred while vehicles were in motion, but Ford isn’t instructing owners to stop driving them. The automaker also revealed they aren’t aware of any accidents related to the issue, but there has been one reported burn injury.

While the investigation is ongoing, Ford and Lincoln will keep owners in the loop and notify them when a remedy is available.