Both the Mustang Mach-E and Ariya have child safety locks to prevent children from opening the rear doors. The Mustang Mach-E has power child safety locks, allowing the driver to activate and deactivate them from the driver's seat and to know when they're engaged. The Ariya’s child locks have to be individually engaged at each rear door with a manual switch. The driver can’t know the status of the locks without opening the doors and checking them.
The Mustang Mach-E has standard Post Collision Braking, which automatically apply the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The Ariya doesn’t offer a post collision braking system: in the event of a collision that triggers the airbags, more collisions are possible without the protection of airbags that may have already deployed.
Both the Mustang Mach-E and Ariya have rear cross-traffic warning, but the Mustang Mach-E has Cross Traffic Braking (automatically applies the brakes) to better prevent a collision when backing near traffic. The Ariya’s Rear Cross Traffic Alert doesn’t automatically brake.
Both the Mustang Mach-E and the Ariya have standard driver and passenger frontal airbags, front and rear side-impact airbags, driver knee airbags, side-impact head airbags, front seatbelt pretensioners, height adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, lane departure warning systems, blind spot warning systems, rearview cameras, rear cross-path warning and driver alert monitors.