As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW RECEIVED AN AFT CARGO DETECTOR CAUTION MESSAGE. MAINTENANCE PERFORMED AN OPERATIONAL TEST OF THE AFT CARGO DETECTOR SYSTEM AND COULD NOT DUPLICATE THE DISCREPANCY. THE AFT NR 1 SMOKE DETECTOR WAS REPLACED AS A PRECAUTIONARY MEASURE. OPERATIONAL CHECKS WERE GOOD AND THE AIRCRAFT WAS RETURNED TO SERVICE.