...and what happens, when all the sensors receive the same information (pressure lines frozen with water, leading to wrong - but not abnormal - parameters messages to flight computers?
FCOM 1.30.50 and 1.34.10 refer. Probes are heated, heating is monitored by ECAM, ducts for ADIRU 1 & 2 are short and independent, chances for all of them to froze simultaneously are appx once in a quintillion hours of operation.