In the past twenty years hundreds of infants and young children have died after being left in vehicles, usually by accident. When turning the vehicle off, drivers of the Elantra N are reminded to check the back seat if they opened the rear door before starting out. The S3 doesn’t offer a back seat reminder.
Over 200 people are killed each year when backed over by motor vehicles. The Elantra N Auto has standard Reverse Parking Collision Avoidance Assist that uses rear sensors to monitor and automatically apply the brakes to prevent a rear collision. The S3 doesn’t offer backup collision prevention brakes.
The Elantra N has a standard blind spot warning system which uses sensors to alert the driver to objects in the vehicle’s blind spots where the side view mirrors don’t reveal them and moves the vehicle back into its lane. A system to reveal vehicles in the S3’s blind spot costs extra.
To help make backing out of a parking space safer, the Elantra N has a standard rear cross-path warning system, which uses sensors in the rear bumper to alert the driver to vehicles approaching from the side, helping the driver avoid collisions. Rear cross-path warning costs extra on the S3.
The Elantra N’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 Elantra N and the S3 have standard driver and passenger frontal airbags, front side-impact 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 and rearview cameras.