What was found
AIRCRAFT WAS NOT GROUNDED: AN EMERGENCY WAS DECLARED AND THE AIRCRAFT RETURNED TO PVR DUE TO THE FLIGHT CREW REPORTING THAT AFTER TAKEOFF AT 1500 FEET MSL AFT CARGO DOOR OPEN LIGHT CAME ON. THE FLIGHT CREW COMPLIED WITH ECAM AND REPORTED THAT THE DOOR WARNING EXTINGUISHED AFTER AIRCRAFT DEPRESSURIZED. THE AIRCRAFT LANDED SAFELY AT PVR AND TAXIED TO THE GATE UNDER ITS OWN POWER. MAINTENANCE FOUND THAT THE AFT CARGO DOOR PROXIMITY SENSOR 32WV HAD DISPLAYED A FAULT ON THE PREVIOUS LEG AND MAINTENANCE REPLACED IT PER AMM 52-71-12. A SATISFACTORY OPERATIONAL CHECK WAS ACCOMPLISHED WITH NO FAULTS NOTED.