What's a G-Sensor or Rough Road Sensor?

I checked me OBD-II on my '96 Trooper (3.2 L 6VD1), and it says I have a G-Snesor low (P1392). I think I have to replace the rough road sensor. Question is where is it on the truck and where can I obtain a replacement? Part # would be awesome!

It helps to prevent rough road effects from being counted as knocks by the knock sensor.
Go to this site for a discussion of it. Ignore the juvenile comments, and, you’ll get “the good stuff”: http://forums.mg-rover.org/archive/index.php/t-6053.html

Check out autozone.com since they have a maintenance area on their website. It shows the part, where it’s located, how to install and the price. Check out rockauto.com as well.