What was found
ACFT EXPERIENCED A VENT BLOWER FAULT MESSAGE ON ECAM, VIBRATION AND ELECTRICAL BURNING ODOR IN THE FLIGHT DECK APPROXIMATELY 20 MINUTES AFTER DEPARTURE. THE FLIGHT CREW ACCOMPLISHED FCOM PROCEDURES AND RETURNED TO DEPARTURE. TECHS FOUND THE AVIONICS BLOWER FAN SEIZED AND THE AVIONICS INLET CHECK VALVE BROKEN. THE FAILED UNITS WERE REPLACED IAW AMM 21-26-51 PB401 & 21-26-56 PB401, NO FURTHER PROBLEMS REPORTED ON SUBSEQUENT FLIGHTS.