As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SATCOM LOCKED UP. NO SATCOM PROMPT ON MCDU MENU PAGE. ACFT GROUNDED. CYCLED SATCOM CIRCUIT BREAKER, NO HELP. SATCOM LRU SHOWS RED LED ON, ALL LED'S SHOULD BE GREEN. REMOVED AND INSTALLED NEW IRIDIUM TRANSCEIVER IAW 23-15-00-400-801. PERFORMED SYS OPS TEST IAW 23-15-00-730-801. SYS CHECKED NORMAL.