As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED DUE TO: FLAPS WOULD NOT EXTEND PAST 15 ON APPROACHAIRCRAFT LANDED SAFELY AT PHX WITHOUT FURTHER INCIDENT. REMOVED AND REPLACED FSEU (FLAP SLAT ELECTRONICS UNIT). PERFORMED SUCCESSFUL BITE TEST OF FSEU. PER AMM 27-51-00. NO DEFECTS NOTED AT THIS TIME.