As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: SLAT FAILED UPON SELECTION OF FLAPS 1. ACCOMPLISHED QRH PRECAUTION, SLATS AND FLAPS EXTENDED NORMALLY. MAINTENANCE PERFORMED SLAT OPERATIONAL TEST AFTER RTS TEST PER AMM 27-80-00-710-801-A AND PERFORMED SATISFACTORY OPERATIONAL CHECK.