As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WITH EXTERNAL POWER AVAILABLE, BUT DESELECTED, AND AIRCRAFT SHUTDOWN (TERMINATED) IF YOU SELECT THE GROUND SERVICE POWER ON OUTSIDE COCKPIT DOOR ALL EMERGENCY LIGHTS TURN ON. REMOVED FROM SERVICE. PERFORMED OPS TEST OF EMERGENCY LIGHTING IAW AMM TASK 33-50-00-710-801-A STEPS 1 THRU 5.B. OPS TEST GOOD, NO FURTHER DEFECTS NOTED.COULD NOT DUPLICATE. RETURNED TO SERVICE. NO PARTS REPLACED.