What was found
SEA FLIGHT NR 2436: 'CHECK PFD 1' AND 'CHECK ED' MESSAGES APPEARED ON TAXI OUT. AIRCRAFT RETURNED TO THE GATE. MAINTENANCE C/W FIM PROCEDURE TASK 31-61-01-810-804 AND TASK 31-61-01-810-807. C/W THE OPS CHECK OF THE NR 1 AND NR 2 PFD'S AND MFD'S AND ED PER MTC 6316104, MTC 6316101 AND AMM TASK 31-61-01-710-803. ALL CHECKS GOOD. CHECKED CDS FOR FAULTS. NO FAULTS NOTED. MESSAGE DID NOT REOCCUR. AIRCRAFT IS CAT III, REMAINS CAT III. PLACARD READS CAT III. MTX CONTROL WAS NOTIFIED. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.