As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN CRUISE FLIGHT, AFT CARGO SMOKE WARNING LIGHT ILLUMINATED. CREW DECLARED EMERGENCY AND DIVERTED TO ALTERNATE AIRPORT. NO FIRE OR SMOKE WAS EVIDENT AFTER LANDING. IT WAS DETERMINED THAT THE WARNING WAS THE RESULT OF A FAULT IN THE AFT CARGO SMOKE DETECTION SYSTEM.