As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU GENERATOR TRIPPED OFF. FLIGHT CANCELLED. APU GENERATOR TRIPPED OFF AND WILL NOT RESET. SEE PREVIOUS FOR FAULT "GEN DIODE". THE GEN HAS ALREADY BEEN REPLACED RECENTLY FOR THE SAME PROBLEM AND "GEN DIODE" WAS THE FAULT REPORTED BY AMSMM. ALSO AMSMM REPORTED INTERMITTENT "FIELD OFF" LIGHT WHEN SHAKING WIRES FROM FIREWALL TO GEN.