If there's an error message "Service Vehicle Soon or Stop Safely Now", the cause is likely bad charger software that should be updated. It's possible that a P2C94 code is present in the SOBDM.
This is according to the TSB:
Issue: Some 2021-2023 Mustang Mach-E vehicles may exhibit a condition where the high voltage battery stopscharging when connected to level 1 or level 2 chargers with an illuminated malfunction indicator lamp (MIL) anddiagnostic trouble code (DTC) P2C94 stored in the secondary on-board diagnostic control module A (SOBDM). Thismay be due to the software in the SOBDM. To correct this condition, follow the Service Procedure to reprogram thepowertrain control module (PCM).
Action: Follow the Service Procedure to correct the condition on vehicles that meet all of the following criteria:• 2021-2023 Mustang Mach-E vehicles• Illuminated malfunction indicator lamp (MIL) and diagnostic trouble code (DTC) P2C94 stored in the SOBDM
Service Procedure
1. Connect a battery charger to the 12-volt battery.
NOTE: To prevent the battery saver mode from activating on the vehicle, make sure the negative cable of the
charger is installed on a chassis or engine ground, and not the 12-volt battery negative terminal. Do not have
the vehicle plugged into the high voltage battery charger during programming. This can cause incorrect
module programming. Make sure only the 12-volt battery charger is installed.
2. Reprogram the PCM using the latest software level of the Ford Diagnosis and Repair System (FDRS) scan tool.
3. Check the availability of software updates on the following modules and update as required:
Secondary on-board diagnostic control module (SOBDM).
Battery energy control module (BECM).
Secondary on-board diagnostic control module B (SOBDMB).
Secondary on-board diagnostic control module C (SOBDMC).
Anti-lock brake system (ABS) module.
This is according to the TSB:
Issue: Some 2021-2023 Mustang Mach-E vehicles may exhibit a condition where the high voltage battery stopscharging when connected to level 1 or level 2 chargers with an illuminated malfunction indicator lamp (MIL) anddiagnostic trouble code (DTC) P2C94 stored in the secondary on-board diagnostic control module A (SOBDM). Thismay be due to the software in the SOBDM. To correct this condition, follow the Service Procedure to reprogram thepowertrain control module (PCM).
Action: Follow the Service Procedure to correct the condition on vehicles that meet all of the following criteria:• 2021-2023 Mustang Mach-E vehicles• Illuminated malfunction indicator lamp (MIL) and diagnostic trouble code (DTC) P2C94 stored in the SOBDM
Service Procedure
1. Connect a battery charger to the 12-volt battery.
NOTE: To prevent the battery saver mode from activating on the vehicle, make sure the negative cable of the
charger is installed on a chassis or engine ground, and not the 12-volt battery negative terminal. Do not have
the vehicle plugged into the high voltage battery charger during programming. This can cause incorrect
module programming. Make sure only the 12-volt battery charger is installed.
2. Reprogram the PCM using the latest software level of the Ford Diagnosis and Repair System (FDRS) scan tool.
3. Check the availability of software updates on the following modules and update as required:
Secondary on-board diagnostic control module (SOBDM).
Battery energy control module (BECM).
Secondary on-board diagnostic control module B (SOBDMB).
Secondary on-board diagnostic control module C (SOBDMC).
Anti-lock brake system (ABS) module.