What was found
ADC1 FAILURE CAUSING EFIS COMP MON, MACH TRIM, L+R FADEC FAULT 2, RUDDER LIMITER FAULT, DUCT MON FAULT,STAB/SLAT FAULT, STAB FAULTWHICH LEAD TO ( RED ) IAS/ALT/VIS [ AT FL340]. RERACKED DCU1 AND DCU2 IAW CRJ 550 AMM 31-41-04 ALL MESSAGES CLEARED NO DEFECTS NOTED AT THIS TIME A/C OKAY FOR SERVICE.