As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EN ROUTE CDG-IAD, LOST RIGHT HIGH FREQUENCY RADIO. DIVERTED TO LHR. *S/D* FAULT, INTERNAL TO THE HIGH FREQUENCY ANTENNA COUPLER (P/N: 792-6140-001) CAUSED THE COUPLER TO RECEIVE BUT NOT TRANSMIT. UNIT WAS REPLACED AND FULL SYSTEM FUNCTIONALITY WAS RESTORED. TESTING VERIFIED REPORT OF RECEIVE BUT NOT TRANSMIT FUNCTION AND ADDITIONAL UNIT ANALYSIS IS SCHEDULED.