Greetings from the Florida Panhandle
I also have a Prodigy Brake Controller which I have had for about 3 years. I have always noticed that two red lights (one lower right corner and the other bottom center of the screen) stay on for awhile after being deactivated. They eventually go off, but if you mess with the manual brake control lever (even with no trailer hooked up) they come on again for a while then go off.
I also have another tow vehicle with the new Tekonsha P3. It acts the same way except the whole screen lights up and stays on for awhile.
SuEllyn & Brian McCabe
WBCCI #3628 -- AIR #14872 -- TAC #FL-7
2015 FC 25' FB (Lucy) with HAHA
2005 Suburban 2500 Quadrasteer (Olivia) & 2011 Silverado 3500 (Fred) with Outfitter Truck Camper (Ethel)