As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AC DEPARTED, ENROUTE, MAIN CARGO COMPARTMENT SMOKE DETECTOR LIGHT ILLUMINATED. AC DIVERTED WITHOUT INCIDENT. INSPECTED AC FOR EVIDENCE OF BURNED WIRES AND FLUIDS. NO EVIDENCE FOUND. INSPECTED CARGO SMOKE DETECTORS AND PERFORMED FUNCTIONAL TEST OF CARGO SMOKE DETECTION SYS. SYSTEM OPERATIONAL CHECKED GOOD.