As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ON CLIMB OUT, FLT CREW REPORTED TOILET SMOKE (W) MSG POSTED. COPLIED WITH QRH AND RETURNED TO DEPARTURE. TOILET SMOKE MSG EXTINGUISHED AFTER COMPLETION OF QRH CHECK. APU ASSY REPLACED AND OPS CHECKED. NO FUTHER DEFECTS NOTED. APU ASSY 3800488-3 P-1012 SEIZED.