The Mustang 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 Civic Si 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 and Civic Si have rear cross-traffic warning, but the Mustang has Cross Traffic Braking (automatically applies the brakes) to better prevent a collision when backing near traffic. The Civic Si’s Cross Traffic Monitor doesn’t automatically brake.
The Mustang has standard 911 Assist, which uses a global positioning satellite (GPS) receiver and a cellular system to remotely unlock your doors if you lock your keys in, help track down your vehicle if it’s stolen or send emergency personnel to the scene if any airbags deploy. The Civic Si doesn’t offer a GPS response system, so if you’re involved in an accident and you’re incapacitated help may not come as quickly.
Both the Mustang and the Civic Si have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, front seatbelt pretensioners, 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.

