As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) WHILE AIRCRAFT WAS IN HEAVY MAINTENANCE, TECHNICIANS DISCOVERED HEAT DAMAGE TO SEVERAL WIRING COMPONENTS FOR THE PASSENGER SERVICE UNIT READING LIGHTS, ON THE LT SIDE OF THE AIRCRAFT JUST AFT OF THE MAIN CABIN DOOR. WIRING SPLICES EXHIBITED SIGNS OF OVERHEATING, AND ADJACENT WIRING WAS HEAT DAMAGED.