The 3 Series Sedan has standard City Collision Mitigation, which use forward mounted sensors to warn the driver of a possible collision ahead. If the driver doesn’t react and the system determines a collision is imminent, it automatically applies the brakes at full-force in order to reduce the force of the crash or avoid it altogether. The A3 has a collision warning system without the crash-mitigating brake feature that could reduce stopping distances.
The 3 Series Sedan has a standard PostCrash iBrake, which automatically applies the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The A3 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.
Over 200 people are killed each year when backed over by motor vehicles. The 3 Series Sedan offers optional Active Park Distance Control that uses rear sensors to monitor and automatically apply the brakes to prevent a rear collision. The A3 doesn’t offer backup collision prevention brakes.
The 3 Series Sedan’s driver alert monitor detects an inattentive driver then sounds a warning and suggests a break. According to the NHTSA, drivers who fall asleep cause about 100,000 crashes and 1500 deaths a year. The A3 doesn’t offer a driver alert monitor.
Both the 3 Series Sedan and the A3 have standard driver and passenger frontal airbags, front side-impact airbags, side-impact head airbags, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, collision warning systems, daytime running lights, lane departure warning systems, rearview cameras, available all wheel drive, blind spot warning systems, rear parking sensors and rear cross-path warning.
For its top level performance in IIHS driver and passenger-side small overlap frontal, moderate overlap frontal, side impact, roof strength and head restraint tests, its standard vehicle-to-vehicle front crash prevention system, its standard vehicle-to-pedestrian front crash prevention system, and its available headlight’s “Good” rating, the Insurance Institute for Highway Safety grants the 3 Series Sedan the rating of “Top Pick” for 2021, a rating granted to only 121 vehicles tested by the IIHS. The A3 has not been tested, yet.