I bought a house and do not know any codes to home system or master code, Is there anyway to reset system , I armed the system unintentionally and had to unplug intire system from AC power and disconnected battery.
you can try doing hardware resett but if the system has been locked down by the installer it wont work and if succesful will need re programming.
if not you have to send the pcb to dsc for reset.
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Try fixfault.com to fix home alarm systems.