As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB AT FL 310, NR 1 ENGINE HAD DUAL FIRE WARNING LIGHTS ILLUM WITH PEGGED NACELLE INDICATORS. PULLED THROTTLE BACK TO IDLE AND LIGHTS WENT OUT, INDICATIONS NORMAL AND CONTINUED FLIGHT. ON GROUND FOUND CSD OVERHEATED AND BODY CRACKED WIRING BURNT ON CSD. REPLACED CSD PER BOEING MAINTENANCE MANUAL 24-11-01.