As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WITH THE NR 2 ENGINE RUNNING, AND GPU DISCONNECTED, ALL ACFT LIGHTS EXTINGUISH. NR 2 DC GENERATOR DOES SHOW LOAD. STARTED THE NR 1 ENGINE, FLT DECK LIGHTS ILLUMINATED AND CABIN EXIT LIGHTS WOULD NOT TURN ON AND FA UNABLE TO TURN ON EMERGENCY LIGHTS. EMERGENCY LIGHTS OPS NORMAL FROM FLT DECK. GROUND RAN ENGINES AND OPERATED ALL AVAILABLE LIGHTS, NR 2 GENERATOR OPERATED NORMAL, OK FOR SERVICE