What was found
AT FL410, THE AMBER GROUND PROX FAIL CAS MESSAGE ILLUMINATED FOLLOWED BY AMBER BLD AIR MONITOR L, GSD FAIL 2, TCAS FAIL CAS MESSAGES. AMBER RA FAIL FLAG ALSO ILLUMINATED. FOLLOWED QRH & USED MANUAL BLOW DOWN. ON FINAL, AMBER AT RETARD FAIL CAS MESSAGE ILLUMINATED. LANDING UNEVENTFUL & TAXIED TO PARKING UNDER OWN POWER. R & R NR 2 GSD. REPROGRAMED NR 2 GSD AS REQUIRED. OPS CHECKS GOOD. WORK DONE IAW MM 31-4-10.