As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ETOPS SIGNIFICANT SYSTEM - TRANSMISSION AND RECEPTION ON L HF INOP. BOTH VOICE AND DATA INOP ON LEFT SIDE. TROUBLESHOOT HF COUPLERS, FOUND NR 2 COUPLER BAD IN BOTH POSITIONS NR 1 COUPLER S/N FK516-01062 INSTALLED IN NR 2 POSITION. COUPLER S/N 0209 INSTALLED IN NR 1 POSITION. NR 1, NR 2 HF SYSTEMS CHECK OK PER MM 23-11-01.