I've read that this feature don't work. It does for me. I start my truck and put it in drive with my foot on brake and then set it. This pulls your rpms down a little. The arrow will go down when I come to a stop or if I'm coasting from about 20 miles an hour. When I shut my engine off it will go down too. If I put my truck in park and foot off brake with engine running it goes up. It works well for me cause when I'm stopped at a light I won't be bothered by signals. Any questions or opinions let me know.