What was found
ON TAKEOFF OUT OF OAK, SLATS DID NOT RETRACT. ALERT FOR SLAT DISAGREE. RAN THE QRH CHECKLIST AND RETURNED TO OAK. CYCLED TWICE. CHECKED PSEU & FCC 1 & 2. PERFORMED PSEU RTS, ALL NORMAL. TESTED SLAT SENSORS MM 27-84-02-5, ALL NORMAL. PERFORMED RTS OF SLAT SYS IN BOTH FCC-1 & 2, ALL NORMAL. NOTICED IN ACARS THAT ALL B-SENSORS SHOWED 0 WITH SLAT HANDLE IN RETRACT POS. FLIGHT CREW VERIFIED SLATS FOLLOWING COMMANDED POSITION, NO BUFFETING APPEARS A DISAGREEMENT INSIDE PSEU INDICATIONS MM 31-71-01-2 AND 45-45-01. REMOVED AND REPLACED PSEU RTS AND CONFIG CODE NORMAL. COMFIRMED BAD PSEU, PSEU SENSOR READOUT L2A NOW SHOWS OK (00) MM 31-71-01-2.