What was found
NR 1 MLG DOOR WOULD NOT CLOSE ON GEAR RETRACTION. PUT GEAR DOWN IAW ECAM, RETURNED FOR LANDING. PERFORMED BITE CHECK OF PROX DET UNIT REF A310 M/M 32-31-71-4, RECEIVED BOX FAULT CODE (BOX LIGHT ON) CODE 64= 28VDC POWER SUPPLY NR 4 OR NR 3,SEE A310 TSM 32-61-00 FAULT ISOLATION PAGE 104.A310 TSM 32-61-00 PAGE 117 SUGGESTS TO CHECK C/B 1GB. FOUND SYS 1 MLG DOOR UPLOCK CONNECTOR CORRODED, REPLACED CONNECTOR AND REPINNED REMOVED AND REPLACED LT MLG UPLOCK ASSY OPS CHECK NORMAL. REMOVED AND REPLACED MLG DOOR ACTUATOR, WITH SERVICEABLE ACTUATOR, OPS CHECK NORMAL IAW MM 32-31-00 P. BLOCK 501. JACKED AC IAE MM 07-11-00-0 THRU STEP C 4. SWUNG GEAR SUCCESSFULLY, NO DEFECTS NOTED.