Hey everyone, i just bought a 2004 ford mustang v6, the cars previous owner had a touchscreen after market In the car and took it out before selling it, i have an aftermarket radio in the car right now, but there is a radio theft system alarm beeping everytime i start the car for about a minute, I've looked all over YouTube and the internet for an answer but I cannot find out how to stop the Beeping. Any help would be greatly appreciated.