As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER PUSHBACK RECEIVED AN APU GEN OFF MESSAGE, ONE RESET ATTEMPT AFTER 5 MINUTES, RECEIVED THE MESSAGE AGAIN. TROUBLESHOT IAW FIM 49-11 F/T 987. RESET THE APU GENERATOR, RAN APU AND APPLIED A LOAD TO THE SYSTEM, NO MESSAGE OR FAULTS NOTED.