As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON ARRIVAL, WHEN BRINGING FLT INTO SCRATCH PAD RECEIVED MESSAGE ON CDU INVALID ENTRY. ACFT GROUNDED. BITE TESTED THE LT AND RT FMC IAW FIM 34-61-00-810-801. NO FAULTS. NO IN FLT FAULTS. SENSORS TESTED OK. CDU KEY TEST OK. CDS FMC INTERFACE OK BOTH FMCS. NO HISTORY 30 DAYS.