As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SATCOM MENU CHOICE IS NOT AVAILABLE ON FMC CDU. ACFT GROUNDED. REPLACED SDU. SATCOM COMMUNICATION SYS TEST MM23-15-00-730-801. OPS NORMAL. SATCOM NR 1 AND NR 2 BOTH SEND AND RECEIVE CLEAR COMMUNICATIONS WITH DISPATCH. ACCOMPLISHED SEVERAL POWER TRANSFERS BETWEEN APU AND EXTERNAL POWER AND ALWAYS RECEIVED SAT PROMT FROM MAIN MENU.