A circuit board assembly for use in a vehicle immobilizer system in accordance with the present invention includes a printed circuit board for mounting in an interior portion of the vehicle and having an aperture formed therethrough. The aperture is defined by an interior wall of the printed circuit board. An antenna trace is printed on the circuit board proximate to the interior wall defining the aperture. An ignition switch assembly extends through the aperture of the circuit board. The ignition switch is operable to receive a key having a transponder disposed thereon, and the antenna trace is operable to alternately transmit a signal to and receive a signal from the transponder when the key is positioned in the ignition switch.