Umm... my Taco just turned off

So I'm cruising through this neighborhood at like 5-10mph and have to make a hard stop because I was half way through passing my left. I move the shifter into reverse, back up a little bit, put it into drive, and press the gas... but it doesn't go anywhere. As I let my foot off the brake, it starts to roll down the hill backwards, I press back on the brake and it's harder. MY power steering is gone... WTF? The thing turned its self off! I put it in park, turn it back on, put it in drive, and carry on my way without issue and it's been about a week, now... What gives?! Anyone have any idea what happened?

 

If you were still rolling backwards when you shifted to D, it will kill the motor.
I found this out when rite after I bought my truck I was playing on the hill in my buddys backyard, tryed crawling it in 2wd and when it stopped going up & rolled back a little it would kill the motor.

 

Oh nuts. Is this lugging the motor or is this a safety switch of some sort? BTW, I work in support and I love how the exact details were actually useful in this case. Haha.

 

I believe it's a safety thing for the transmission, like you I freaked the first time it did it, then I had to figure out what was happening so I did it again & again till I figured out it was some type of safety thing.