As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FOUND MAINT MSG NR 73 31691 (ADIRU 1 AND ADIRU 2 TAT DATA FROM DEU 1 AND DEU 2 IS MISSING) FOR NR 1 ENGINE. CLASSIFIED AS A LONG TERM FAULT DEFERRED FOR 450 FLT HOURS PER T/C 78273000. UNABLE TO DUPLICATE. NO FAULTS LOGGED LAST 10 FLIGHTS. NO FAULTS ON EITHER ADIRU. OPS NORMAL.