As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 0051 - RETURNED TO GATE DUE TO STRONG ELECTRICAL ODOR COMING FROM THE FORWARD LAVATORY. MAINTENANCE IDENTIFIED BURNING ODOR WAS COMING FROM FORWARD LAVATORY SMOKE DETECTOR. REMOVED AND REPLACED SMOKE DETECTOR, OPERATIONAL CHECK GOOD PER BMM 26-14-00.