The National Highway Traffic Safety Administration (NHTSA) has opened an investigation into if a prior recall remedy issued by Ford was adequate, Autoblog reports.
The recall being investigated was first issued in 2022 on nearly 49,000 Ford Mustang Mach-E electric vehicles manufactured between May 27, 2020, and May 24, 2022.
The vehicles were recalled due to an issue with high voltage battery main contactors overheating from DC fast-charging and repeated wide-open pedal events and resulting in an immediate loss of power.
As a remedy, Ford had a Secondary On-Board Diagnostic Control Module (SOBDMC) software update implemented to monitor contactor temperature and reduce battery power, as well as a Battery Energy Control Module (BECM) software update to monitor contactor resistance and reduce vehicle power if needed, according to NHTSA documents.
Following this, a technical service bulletin was sent out by Ford stating to replace High Voltage Battery Junction Boxes in recalled vehicles.
Since then, the NHTSA has received 12 consumer complaints detailing a high voltage battery main contactor failure in vehicles covered by the 2022 recall, resulting in a loss of motive power.
The vehicles in the complaints received the initial recall remedy as well as the technical service bulletin’s recommended replacement, prompting a recall query from NHTSA.