As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LOWER AFT BODY OVERHEAT LIGHT ILLUMINATED IN CRUISE FLIGHT. (NO ANTI-ICE ON AT ALL). NR 2 ENGINE LEFT BLEED ON NR 3 BLEED ON, LEFT AND RIGHT PACKS ON. FOLLOWED RED TABS PROCEDURES. LIGHT WENT OUT AFTER NR 1 ENGINE BLEED TURNED OFF FOR SEVERAL MINUTES. RAN ALL ENGINES ON GATE. NO DEFECT NOTED. REMOVED AND REPLACED OVERHEAT DETECTION UNIT, (PRECAUTIONARY).