What was found
MAIN DOOR: AT FLIGHT LEVEL 320, THE CHECK DOOR AND CABIN DOOR OPEN EICAS MESSAGE DISPLAYED. COMPLIED WITH THE CHECKLIST. GAINED ACCESS TO L/H PCB ENCLOSURE ,REMOVED PCB NC105 P/N 7468101-17 1 S/N 0408, INSTALLED CUSTOMER SUPPLIED NEW PCB NC105, P/N 7468101-17 , S/N 0470, PERFORMED OPERATIONAL CHECK, ALL CHECKS GOOD, NO FAULTS FOUND, REASSEMBLED L/H PCB ENCLOSURE, AT-, D RETURNED AIRCRAFT TO INITIAL CONDITON, REF AMM 24-60-40 52-10-00.