As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 1751 - SJU - DFGS 2 WHEN SELECTED WILL NOT CAPTURE VOR RADIAL COURSE BECAUSE THE SYSTEM WILL NOT ARM. IT WILL ARE THE LOCK INSTEAD BUT THERE IS NO LOCALIZER FRQ DIALED IN. AUTOPILOT WILL DISENGAGE DFGS NR 1 WORKS FINE. REMOVED AND REPLACED NR 2 VHF/NAV CONTROL PANEL PERFORMED RTS CHECK TEST SYSTEM GIVES 'GO' INDICATION. (M)