How many alerts do you need to remember that you’ve left your child in the back seat" Several, according to Hyundai, which is set to become the third automaker to install rear-occupant alert technology. But whereas similar systems in General Motors and Nissan vehicles monitor whether rear doors have been opened and closed, Hyundai?s new Rear Occupant Alert uses sensors that detect movement in the rear seat.

If someone is detected in the back, when the driver exits the vehicle a message reading Check Rear Seats displays on the center instrument cluster. And if the driver leaves the vehicle, the system will then honk its horn, flash its lights, and send a notification to the driver’s smartphone via Hyundai’s Blue Link connected-car system. Hyundai is rolling out Rear Occupant Alert in select 2019 vehicles. GM introduced its own Rear Seat Reminder in the 2017 GMC Acadia and has since been expanding it across several Buick, Cadillac, Chevrolet, and GMC models. In August, Nissan announced it would add the Rear Door Alert to the 2018 Pathfinder, with other models to follow. Both GM’s and Nissan’s systems monitor the rear doors for activity, and both display a reminder message on the instrument cluster as the driver is exiting the vehicle. GM’s emits a series of chimes, while Nissan’s can chirp the horn. Both can be deactivated. And Hyundai’s will be able to be shut off as well, a company spokesman told Car and Driver.

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