For enhanced safety, the front and rear seat shoulder belts of the Acura TLX have pretensioners to tighten the seatbelts and eliminate dangerous slack in the event of a collision and force limiters to limit the pressure the belts will exert on the passengers. The Audi S3 doesn’t offer pretensioners for its rear seat belts.
The TLX Type S has a standard Surround View Camera System to allow the driver to see objects all around the vehicle on a screen. The S3 only offers a rear monitor and front and rear parking sensors that beep or flash a light. That doesn’t help with obstacles to the sides.
The TLX has a standard blind spot warning system that uses sensors to alert the driver to objects in the vehicle’s blind spots where the side view mirrors don’t reveal them. A system to reveal vehicles in the S3’s blind spot costs extra.
To help make backing out of a parking space safer, the TLX has standard Rear Cross Traffic Monitor, helping the driver avoid collisions. Audi charges extra for Rear Cross-Traffic Assist on the S3.
The TLX’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 S3 doesn’t offer a driver alert monitor.
Both the TLX and the S3 have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, 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, rearview cameras and available all wheel drive.