What was found
DURING CLIMB OUT PASSING 5000 ATS LEVER TRIPPED OFF AND WE LOST POWER TO THE ENTIRE FCP. NO FLIGHT DIRECTORS, NO FMAS. TRIED RESETTING ATS LEVER AND PITCH TRIM AND YD LEVERS. NO LUCK. AIR TURN BACK. MANUALLY FLOWN AND NO AUTO THROTTLES. AMM: 22-15-12-04 AMM: 22-10-00-05 AMM: 22-40-00-05 UPON ARRIVAL TO ACFT, CHECKED FAULTS ON MAINT PANEL. FOUND FCU FAULTED. REMOVED AND REPLACED FCU. ALIGNED IRS 3 TO PERFORM AFS LAND TEST. PERFORMED AFS LAND TEST. OPS CHECKS GOOD. NO FAULTS NOTED. A/C BACK TO NORMAL CONFIGURATION.