As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE FLIGHT RETURNED TO DEPARTURE DUE TO STRONG ELECTRICAL SMELL IN THE FLIGHT DECK. THE FWD LAVATORY SMOKE DETECTOR ALSO WAS SOUNDING. GALLEY POWER WAS SELECTED OFF AND SMELL DISSIPATED. LANDING WAS UNEVENTFUL. MX COULD NOT DUPLICATE THE ELECTRICAL SMELL ON THE GROUND. NO EVIDENCE OF FIRE, BURNING, NOR OVERHEATED COMPONENTS OR MATERIAL WAS FOUND.