I guess no one remembers in the parking lot of the Fontana village in 2011 when my Megellan gps did the same thing. in fact i stopped at walmart and bought a garmin thinking mine was bad. in the parking lot that afternoon, with Rudy and 10 to 15 other people,all with their GPS in hand and my two of them,,, once anyone got NEAR my car (with my engine running) their aftermarket gps would not work, we tried everything to make the gps's work,trying everything to shut off the single from the car. so the aftermarket gps would work, ,after a while maybe 1 1/2 hours, Rudy said he could disconnect the antenna to see if that would work, once the antenna was disconnected ALL the aftermarket gps's worked fine,, we also tested the above with 8 or 9 other cars including two other srt6"s none of them stopped the gps's from working except my car, About 3 weeks ago, 7 years later i connected my antenna to my radio ,,,,,,the funny part is,,when i connected my antenna someone somewhere with a crossfire, their aftermarket gps stopped working,,,boy does my car have power lol. jim