As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UNABLE TO TRANSMIT ON HF #2 FROM ANY TRANSMIT SWITCH. AFTER SOME TIMES WE FINALLY WILL GET SIDE TONE, BUT AFTER SWITCHING FREQUENCIES, NO SIDE TONE HEARD. ABLE TO RECEIVE VOICE AND SELCAL ON HF#2. GROUNDED - YES. ACCOMP #2 HF TRANSCEIVER BITE TEST, TEST PASS BUT FAN MOTOR MAKING EXCESSIVE NOISE DURING TEST. OPEN C/B & INST. REPLACED #2 HF TRANSCEIVER WITH SERVICEABLE ONE. ACCOMP INSTL TEST, TEST PASS REF. B737-900 AMM 23-11-21-400-801 ALSO ACCOMP GROUND COMMUNICATION TEST.