As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FVR FOR HF1 OP CK UNSUCCESSFUL. ABLE TO HEAR AND OTHER AIRCRAFT ON HF # 1, BUT UNABLE TO VERIFY TRANSMISSION CAPABILITY. GROUNDED - YES. REMOVED AND REPLACED NO 1 HF TRANSCEIVER AND NO 1 HF COUPLER REF AMM 23-11-21 AND AMM 23-11-61, ETOPS SIGNIFICANT SYSTEM GROUND TEST SUCCESSFUL REF AMM 23-11-61.