As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) SHORTLY AFTER PUSHBACK, SMOKE STARTED COMING INTO THE CABIN THROUGH THE VENTS. CREW RETURNED TO GATE FOR DEPLANING OF PASSENGERS AND MAINTENANCE INVESTIGATION. FOUND QSEB 11K AT AFT RT J CLOSET INTERNAL CIRCUIT BOARD SHORTED DUE TO EVIDENCE OF DRIPPING WATER CONTAMINATION FROM TOP SHELF. REPLACED BOTH QSEB IN AFT RT J CLOSET IAW AMM 44-+22-78-470-02A01. IP SEQ AND P2 SW DL CARRIED OUT.