What was found
PHL - FLT 754 - AFTER TAKEOFF, EICAS INDICATED LAVATORY SMOKE. RETURNED TO BASE, PHL. INSPECTED LAVATORY TRASH CONTAINER AND FIRE BOTTLE, ALL NORMAL. ALL VISIBLE WIRING AND ELEC CONNECTORS ALL NORMAL. CHECKED AFT CARGO AND APU COMPTS, ALL NORMAL. RAN APU, AIR COND, ENGS, ALL NORMAL. EICAS AND SMOKE DETECTOR SYSTEM OPS CHECK NORMAL. (X)