What was found
TYS - AIR RETURN - LAV SMOKE INDICATION ON CLIMBOUT. ONCE ON GROUND F/A REPORTED, THERE WAS A LOT OF HEAT COMING FROM BEHIND THE EXIT ROW, BUT NO VISIBLE SMOKE. MX FOUND AND REPAIRED A BROKEN GROUND WIRE ON THE THERMAL DISTRIBUTION SWITCH IAW EMB 145XR WM 20-21-00 AND OPS CHECKED GOOD IAW EMB 145XR AMM 21-20-00 AND EMB 145XR AMM 26-14-00. A SATISFACTORY TEST FLIGHT WAS ALSO PERFORMED AND THE A/C WAS RELEASED BACK TO SERVICE.