An apparatus and a method for saving power of a mobile station. The power detection system includes a detector having an output and a return which are coupled together by the device when the device requires power. A person installing the immobilizing device on a vehicle utilizes the user interface to enter and store an unlock code and an identification code in the device memory at the time of installation. The feedback transistor may be connected in parallel across each of the input transistors so that when one input voltage increases above or decreases below the input voltage at the second input by a predetermined threshold value, the feedback transistors operate to provide positive feedback to facilitate a rapid switching action at the output. The magnets are carried by a magnet carrier that is disposed radially inwardly of the armature windings of the stator so as to provide a compact assembly. The invention is applicable to household appliances for cooking under pressure.