What was found
AIRCRAFT RETURNED TO THE GATE FROM TAXI FOR A NAVIGATION SYSTEM PROBLEM. DURING TROUBLESHOOTING SOME POPPED CIRCUIT BREAKERS FOR LIGHTING FOUND POPPED IN THE LOWER ELECTRONIC COMPARTMENT, WOULD NOT RESET. MINUTES LATER A PASSENGER REPORTED A POPPING NOISE ABOVE SEAT ROW 29, LEFT SIDE OF CABIN. A MECHANIC CHECKING THE SOUND OPENED THE COVE LIGHT PANEL AND FOUND SMOKE. FANNING THE AREA TO CLEAR THE SMOKE, A SMALL FLAME DEVELOPED. THE MECHANIC USED HIS HAND TO EXTINGUISH THE FLAME. PASSENGERS WERE DEPLANED. SOME 19 WIRES WERE DAMAGED AT STA 1085, LBL 53, WL 305, BUNDLE 6035. REPLACED SECTION OF DAMAGED WIRES PER STD PRACTICES 20-41-01 AND 20-51-01. CHECK-C 10-29-99.