As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ETOPS SIGNIFICANT SYSTEM - LEFT HF RADIO WILL NOT CHANNELIZE ON CERTAIN FREQS AND WILL NOT TRANSMIT ON ALL FREQS, DATA MODE OPERATES NORMALLY. TROUBLESHOT PER FIM 23-11-00-1. FOUND RIGHT HF COUPLER BAD. REMOVED AND REPLACED RIGHT HF COUPLER PER AMM 23-11-01. OPS CKS GOOD. BOTH HF RADIO'S CKS GOOD 3B Y3 WITH SFO ARINC, SELCAL OPS NORMAL.