As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA FLIGHT NR 2398: RETURN TO GATE, AFTER PUSH AND DISCONNECT FROM TUG WHEN THE CONDITION LEVERS WERE BROUGHT TO MAX, THE PROPS CAME UP NORMALLY. BUT WHEN AUTOFEATHER WAS SELECTED THE NR 2 PROP FEATHERED. NR 1 PEC CAUTION ILLUMINATED WITH NR 2 AC GEN POWER PLANT MESSAGE ON ED. MAINTENANCE REMOVED AND REPLACED THE NR 2 PCU, CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.