What was found
ADVISED FLIGHT CONTROL 15 MINUTES AFTER DEPARTURE THAT THEY WERE RETURNING TO DEPARTURE. ACFT HAD NR 3 WINDOW HEAT AND LANDING GEAR EICAS MESSAGE COMING OUT OF A "C" CHECK. T/S TESTS FOUND OPEN IN NR3 SENSOR LOOP FOUND BROKEN TERMINAL AT PIN 5 OF D415 96P, RETERMED IAW WPM 20-60-01 OPS CHECK GROUND. ON GEAR FOUND FAULT CODE 078 ON PSEU. FOUND BEAR WIRES ON PROX SENSOR S10078 WERE SHORTING. REP EPAIRED WIRE IAW SWPM AND CHECK GAP ON PROX SENOR S10078. GAP CHECK GO OD IAW AMM.