A method and medical system for operating three electrodes electrically coupled to three proximal contacts carried by three lead bodies is provided. The electrodes are implanted adjacent tissue of a patient and include a middle electrode and a pair of electrodes flanking the middle electrode. Electrical energy is conveyed between three different pairs of the proximal contacts, thereby respectively generating three electrical fields in the tissue between three electrode pairs. A potential of each of the electrical fields is measured at the remaining electrodes via the remaining proximal contacts, respectively. The lead body associated with the middle electrode is identified based on the measured electrical field potentials.