As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING PREFLIGHT HF 1 RADIO DISPLAYS FAIL IN ACTIVE & STANDBY WINDOWS. GROUNDED - YES. REBOOTED #1 HF XCVR. OPS CK OF #1 HF SYS OK REF B737-900 FIM 23-11 TASK 802 & 23-11 TASK 801 NORM OPS RESTORED #1 H/F BITE CK OK. VERIFIED H/F #1 XMITS NORM ON GROUND. ETOPS GROUND VERIFICATION COMPLETE.