Grandmother freaks out behind wheel of Tesla's self-driving car

This grandmother will do the driving herself, thank you very much.

Bill Rimmer, who owns the Tesla Model S, took his mother for a ride and activated the autopilot mode while filming her.  She completely freaked out.

"This is so scary! Oh Jesus, this is my first day out and I am about to die!" she says.

By keeping her hands clutched to her breast in abject terror, she was unknowingly allowing autopilot to continue by not touching the steering wheel or pressing the brake.

Automotive expert Lauren Fix told Inside Edition, "Once you set your autopilot on a highway, you are supposed to still pay attention and still have your hands ready to go at all times. You are not to have your hands or arms crossed."

Rimmer finally reached out and turned the steering wheel slightly, bring his mother's terrifying ride to an end.

The Tesla S, which comes with 12 ultra-sonic sensors and radar that allows it to independently change lanes, speeds and even self-park, sells for more than $100,000.