What was found
EN ROUTE NOTICED FAINT ELECTRICAL SMELL, SWITCHED TO FRESH AIR MODE, ODOR DIMINISHED, BUT STILL PRESENT. ON APPROACH SWITCHED TO APU AIR ODOR GONE. MAINTENANCE RAN ENGINES, TESTED ON ALL AIR SOURCES, INSPECTED BEHIND OVERHEAD ELECTRICAL, REPOSITIONED RUBBER SLEEVE ON OVERHEAD ELECTRICAL PANEL LANYARD.