What was found
DURING CLIMB OUT, LEFT PFD ATTITUDE INDICATOR REMOVED, RED FD, ATT ,AND HDG FLAGS DISPLAYED ON PFD, ACCOMPANIED WITH AUTOPILOT DISCONNECT AND YD 1 INOPERATIVE AND PITCH FEEL FAULT STATUS MESSAGES. INTERROGATED MDC FOUND B1 CODE 005923 AND MULTIPLE OTHER ONES WHERE THE POSSIBLE CAUSE IS AHC 1. R & R AHC 1 IAW AMM 34-21-01-000-400-801. OPS CHECKED GOOD.