Ford Mustang Mach E Software Error May Cause Unintended Acceleration

A small number of 2021 Ford Mustang Mach E vehicle owners will be contacted by the manufacturer regarding a problem with the powetrain control module (PCM) software in their cars. The problem could lead to vehicle unintended acceleration and an accident.

Ford's critical concern review group (CCRG) first became aware of the problem in March 2022 after receiving reports of a Mustang Mach E incorrectly detecting a lateral hazard on the primary axle. As a result of the incorrect detection, the vehicle automatically shut down and entered a speed-limited state. An investigation into the problem found the software was incorrectly updated to a later model year/program file causing the functional safety software to always report a torque value of zero on the secondary axle. This would cause the functional safety software to ignore a possible unintended acceleration, unintended deceleration, or unintended vehicle movement on the secondary axle and/or incorrectly detect a lateral hazard on the primary axle. Unintended acceleration, unintended deceleration, unintended vehicle movement, or a reduction in motive power could increase the risk of a crash. This condition may be accompanied by illumination of the malfunction indicator lamp or wrench light.

Ford's review of vehicle service records determined the population of the affected vehicles and is capable of tracing the powertrain control module software to the vehicle in which the powertrain control module was installed.

The remedy for this program is a powertrain control module software update. Ford is anticipated to begin Over-The-Air (OTA) deployment to update the powertrain control module software for affected vehicles in May 2022. Alternatively, owners will have the option to take their vehicle to a Ford or Lincoln dealer to complete the software update. Affected vehicles are equipped with all wheel drive. Ford's number for this recall is 22S29 and the NHTSA campaign number is 22V-333.