What was found
PILOTS DETECTED A BURNING WIRE SMELL IN THE COCKPIT, SEEMED TO DISSIPATE AFTER TAPPING LEFT MASTER CAUTION PANEL. PILOT EXECUTED AN AIR TURNBACK. WHILE INSPECTING THE CAPT'S MASTER CAUTION WIRING HARNESS, NOTICED A TERMINAL ON THE MASTER CAUTION HAD COME OFF AND TOUCHED AN ADJACENT TERMINAL. NO DAMAGE WAS NOTED, SO TERMINAL WAS RECONNECTED MASTER CAUTION, OPS CK GOOD.