Ford has halted deliveries of the Mustang Mach-E electric SUV due to an issue with its high-voltage system that might lead to a loss in power. 

The issue affects 48,924 of the vehicles built from May 2020 through late May 2022. 

“On affected vehicles, Direct Current (“DC”) fast charging and repeated wide open pedal events can cause the high voltage battery main contactors to overheat,” according to Ford, which can cause the contact surfaces to deform. 

2021 Ford Mustang Mach-E

2021 Ford Mustang Mach-E

That might potentially result in a situation where the overheated contactor opens while driving, leading to a loss of power. Ford also mentions the possibility of a contactor that “welds closed” from the conditions—although, to speculate, the latter is likely a condition that various existing failsafes would quickly detect. 

There are no open safety investigations from NHTSA on the matter. 

Ford emphasizes that the issue is not a stop-sale. Dealers can still sell the Mach-E, but they can’t yet deliver it. 

The fix is entirely via an over-the-air update. That will bring revised software for two control modules: the Secondary On-Board Diagnostic Control, and the Battery Energy Control Module. The update is due next month—in July—or, Ford says, owners will be able to take their vehicles to the dealership to have them complete the software update.

Ford Mustang Mach-E, downloading update!

Ford Mustang Mach-E, downloading update!

Although Ford has already tackled other recalls for the Mach-E, this isn’t the first one that it’s solved entirely over-the-air. The Mach-E was one of the first mass-produced U.S.-market vehicles outside of Tesla vehicles to have the full potential of over-the-air firmware updates enabled from the start. That not only gives Ford an advantage for recalls such as this; it also will allow the automaker to potentially boost range and perhaps performance with future updates.