Methods and systems are disclosed that utilize FM tuner ground isolation when using a ground signal line as an FM antenna for an FM tuner integrated circuit (IC) within a portable electronic system. The ground isolation can be implemented, for example, using one or more isolation elements, such as ferrite beads, coupled between the FM tuner ground and the device ground. The ferrite beads can also be coupled between other pins for the FM tuner and the device circuitry. A car lighter adapter (CLA) coupled to the device circuitry can be configured to provide a ground signal line for use as an antenna for the FM tuner IC. Further, signal lines on a printed circuit board (PCB) can also provide a ground signal line for use as an antenna for the FM tuner IC. The device can also be as a personal navigation device.