As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SATCOMS 1 AND 2 COULD DIAL AND RECEIVE DISPATCH COMMUNICATION, BUT COULD NOT TRANSMIT SUCCESSFULLY. ACCOMPLISHED QRH FOR POSSIBLE LOCKUP ISSUE, DID NOT FIX THE PROBLEM. ACFT GROUNDED. ACFT CHECKED & RELEASED IAW MEL 23-18, SATCOM 1 & 2 INOPERATIVE. R & R REU IAW AMM 23-51-01. OPS CHECK NORMAL. PERFORMED OPS CHECK OF SATCOM SYS IAW AMM 23-15-00-730-801. OPS CHECK NORMAL. MEL 23-18 CLEARED.