What was found
DURING APPROACH, WHEN CONFIGURING FROM FLAPS 1 TO 5, RECEIVED TRAILING EDGE FLAP DISAGREE. FLAP INDICATOR STAYED AT FLAPS 1 WITH THE FLAP HANDLE IN FLAPS 5 DETECT. COMPLIED WITH QRH. USING ALTERNATE SYS CONFIGURED TO FLAPS 20 FOR LANDING IAW QRH GUIDANCE. REPLACED ALT FLAP POSITION SWITCH S598. PERFORMED FSEU BITE TEST, TEST PASSED. RAN FLAPS THROUGH SEVERAL CYCLES USING HYD & ALT DRIVE SYSTEM. R & R FSEU PERFORMED BITE TEST & FLAP POSITION TRANSMITTER CHECK. ALL CHKD GOOD. AFTER COMPLETION OF INSTALL, TESTS RAN FLAPS AGAIN & T/E FLAP DISAG LIGHT & ECIAS MESSAGE CAME ON FOR ABOUT 1 SEC. PERFORMED FSEU BITE TEST AGAIN, CLEARED STORED FAULTS ON FSEU, PERFORMED OPS CHKS & OPS FLAPS WITH C1 & ADP HYDS. OPS CHK PASSED. COULD NOT GET T/E LIGHT TO ILLUMINATE. UTILIZING THE C1 PUMP ONLY DOES NOT SUPPLY ENOUGH PRESSURE OR VOLUME TO MOVE FLAPS FAST ENOUGH TO NOT TRIGGER T/E MESSAGE. COMPARED 281 TO ANOTHER SERVICABLE & DOES SAME THING. LIGHT COMES ON AFTER AT SET PERIOD & GOES OUT ONCE FLAPS CATCH UP. BUT UTILIZING ADP, LIGHT DOES NOT COME ON. ALSO PERFORMED CONTINUITY CHKS OF ALT FLAP SWITCH FROM D10032 - D1836B. NO DEFECTS NOTED. ACFT OK FOR SERVICE.