Tesla’s touchscreen trouble: NHTSA asks for recall of Models S and X

In November, we learned that the National Highway Traffic Safety Administration had opened an engineering analysis into a potential defect with Tesla’s popular Models S and X battery electric vehicles. On Wednesday, the other shoe dropped, when NHTSA informed the American automaker that it has to recall 158,000 vehicles to fix defective touchscreens.

The problem concerns a component in the vehicles’ infotainment systems, called the Media Control Unit. Buried within the MCU is an 8GB eMMC NAND flash memory chip, which can only be written to a finite number of times. Once this number of read/write cycles is reached—something that takes between three and four years depending on how much the car is driven—the touchscreen dies. And unfortunately, that’s a real problem in a car where the touchscreen is the way almost all the controls are accessed.

Not being able to browse the Internet in your car or stream a podcast is obviously an inconvenience, especially in an high-end vehicle. But NHTSA is more concerned about the fact that if the touchscreen dies, functions like the backup camera and window defogging are lost, too, as are audible alerts for other onboard safety systems.