Technical Service Bulletin SSM 54334 — 2025 FORD MUSTANG MACH E

Some 2023-2025 Mustang Mach-E vehicles equipped with a lithium iron phosphate (LFP) standard range battery (minor feature code HTHAH) built on or after 23-Jun-2023 may exhibit a condition where the displayed high voltage (HV) battery state of charge (SOC) percentage has a sudden reduction greater than 10% while driving. At low SOC, this may also result in a reduction of vehicle power with a turtle light displayed in the cluster. This concern may occur if the vehicle has not been charged to 100% for an extended period of time as this leads to an inaccurate displayed SOC. Advise customers to charge their vehicle to 100% at least once per month to reset the SOC measurement or more often if the condition persists. To confirm a vehicle is built with a certain minor feature code, review the build information by double-clicking the vehicle identification number (VIN) in the upper left corner in the Professional Technician System (PTS).