As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SMOKE TOILET CAUTION MESSAGE ON TAKEOFF CLIMB, COMPLIED WITH QRH, AIR RETURNED TO PHL NO OVERWEIGHT LANDING WTW 41,000 LBS. NO VISUAL SMOKE IN LAV OR CABIN. (M) REMOVED AND REPLACED PRESS REGULATING VALVE ASSY ON RT ENG IAW AMM 25-31-05. PERFORMED COMP WASH AND POWER RUNS NO SMELLS NOTED AND NO SMOKE NOTED THROUGH ALL POWER RANGES, OK FOR SERVICE. (K)