As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LAX - WITH EXTERNAL POWER PLUGGED IN, THE AC GREEN POWER LIGHT CYCLES OFF AND ON AND A BURN ODOR IS NOTICED. MAINTENANCE PLUG IN EXTERNAL POWER AND APPLIED POWER FOR OVER 15 MINUTES. LIGHT WAS STEADY GREEN AND THERE WAS NO BURN ODOR NOTICED. AIRCRAFT RETURNED TO SERVICE. NO PARTS REPLACED.