2008 Prius. Never had any warning lights before. Had an installer put in some screens and a reversing camera yesterday. He had to take the dash apart a bit, of course, and he also disconnected the 'park' sensor. The only other thing of note he did was connect into the red reversing sensor wire, so the reversing camera knew when to turn on. Afterwards, get the red triangle warning light on the display, and an icon on the top-left of the MFD (car profile outline with a ! in the middle). Left the car alone for a while, with doors shut etc, as mentioned on this thread by F8L: http://priuschat.com/forums/gen-ii-...38682-problem-aftermarket-stereo-install.html But the warning is still there 10 min later. Left it overnight though, and warnings have gone Thanks F8L !