As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX - FLIGHT 9850 (PART 91 OPERATIONAL CHECK FLIGHT), ON TAKEOFF ROLL AT 100 KNOTS RECEIVED A LAV SMOKE DETECTOR MESSAGE. ABORTED TAKEOFF. MAINTENANCE REPLACED THE LAVATORY SMOKE DETECTOR. OPERATIONAL CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.