As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ASH FLT 7347 IAD-DAY. LAV SMOKE CAUTION WITH MANUAL HEAT ON. EMERGENCY WAS NOT DECLARED. A LIGHT SMOKE WAS SEEN IN THE CABIN. CREW HAD PACK ON MANUAL HEAT, WHICH CREW BELIEVES CAUSED THE SMOKE AND THE DETECTION IN THE LAV. MX PERFORMED THOROUGH OP CHECKS OF THE LAV SMOKE DETECTION SYSTEM AND THE PACKS AND TEMP CONTROL SYSTEMS WITH NO FAULTS FOUND.