A Tesla Model S owner took to Reddit on Tuesday to share the story of how a giant moth knocked out Autopilot, the system that lets some Tesla's drive themselves, on his car.

The giant moth managed to fly right into the single forward-facing radar sensor on the Model S, which is located towards the bottom of the car's fake grille. (There are 12 other ultrasonic sensors around the car, but this was the only front-facing sensor.)

Here's an account of the story, courtesy of Reddit user and Model S owner Redebo:

There I was, cruising along on [Autopilot] doing 85mph on a lonely stretch of 93 between Kingman and Las Vegas. SUDDENLY, my driver console flashes red and commands me to take control of the vehicle. AP drops off. Cruise control drops off and I get the ominous warning, "Radar visibility has been reduced." I see a lone gas station up the road and slow my roll into the fluorescent lighting of the canopy covering the gas pumps. I step out of the car while a car of German exchange students look quizzically at a [Model S] parked next to a pump. Fearing the worst, I peek around the front of the car and was confronted with this sight. The Demon Spawn of Mothra had attacked me and rendered my autonomy useless. Never fear though, a quick scrape with the window squeegee over the radar opening and my technology was restored!

We reached out to Tesla about this story. The company tells Tech Insider that it's pretty uncommon for a bug of this size to fly into the radar sensor and cover a large majority of its area. Also, if this driver was driving the newly-redesigned Model S, this wouldn't have happened. The exposed sensor on the older model is now concealed behind the front bodywork of the car's new nose, which no longer has any kind of fake front grille.

And here's what the Model S owner's manual has to say about these kinds of obstructions affecting Autopilot:

Autosteer is unable to accurately determine lane markings due to poor visibility (heavy rain, snow, fog, etc.), or an obstructed, covered, or damaged camera or sensor. Many unforeseen circumstances can impair the operation of Autosteer. Always keep this in mind and remember that as a result, Autosteer may not steer Model S appropriately. Always drive attentively and be prepared to take immediate action.