What was found
AUTOPILOT DISENGAGED AND THEN WE HAD A COMPLETE NAVIGATION FAILURE ON THE PFDS AND THE MFD. FMS DATA WAS REMOVED. RED FLAG BOXES ON THE PFD WERE FMS, FD, AND RA. THE MOVING MAP, RUDDER BOOST , CDU, AND TRANSPONDER, FAILED. THE RTU WAS ONLY ABLE TO INPUT COM1/NAV 1 FREQUENCIES. REMOVED L/H IAPS POWER SUPPLY P/N 822-1137-001 S/N 41GRFVL. INSTALLED REPAIRED IAPS POWER SUPPLY P/N 822-1137-001 S/N 28NNH. REF B300AMM31-40-03 OPS CHECK GOOD.