As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE FLIGHT RETURNED TO GATE WHEN THE CREW NOTICED THAT THE OUTBOARD SPOILERS GROUND SPOILERS DO NOT EXTEND WHEN THE FLIGHT/TAXI SWITCH IS IN THE FLIGHT MODE. MAINTENANCE INSPECTED THE AIRCRAFT AND PLACED THE SYSTEM ON MEL. THE SPOILER POWER UNIT WAS FOUND BAD AND WAS REPLACED. OPERATIONAL CHECKS WERE GOOD AND THE AIRCRAFT WAS RETURNED TO SERVICE.