As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING TAXI PRIOR TAKEOFF, BOTH ENGINES SHUTDOWN WITHOUT PILOTS INPUTS, ACFT RETURNED TO GATE. DURING INITIAL TROUBLESHOOTING MECHANICS WERE ABLE TO REPRODUCE THE EVENT ADVANCING PLA SLOWLY. OUTSIDE TEMPERATURE REPORT AT TIME OF THE EVENT -30C.