What was found
THIS PARTICULAR PFD HAD 3 BACK TO BACK FAILURES THAT COULD ONLY BE DETECTED AFTER 1 HOUR + OF FLIGHT. DISPLAY WOULD LIGHTEN UP, TURN GREEN AND FLICKER. WOULD NOT BE USABLE. THIS UNIT WAS UPGRADED TO REV 6 SOFTWARE FOR FLIGHT DIRECTOR. FAILURES HAPPENED AFTER THIS MOD. FAILURES HAPPENED AFTER THIS MOD UNIT WAS SENT TO MFG AFTER FIRST 2 FAILURES, THIRD FAILURE RESULTED IN AN EXCHANGE. (1ST-3-6-06-W/O AVO6-6617) (2ND - 3-29-06, W/O AVO6-6658) (3RD-4-4-06 W/O AVO6-6687)