As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE FL 370, NR 1 ENG EGT WENT TO 965C EGT, EGT IN NORMAL RANGE AT IDLE. ALL OTHER ENG INDICATIONS NORMAL. FOUND NR 1 ENG LT EGT THERMOCOUPLE PROBE SHORTED WHEN TROUBLE SHOT HIGH ENG EGT. REPLACED THERMOCOUPLE PROBE HARNESS. ACCOMPLISHED TASK IAW ECRA 7700-01129. NR 1 ENG RAN & TESTED NORMAL.