What was found
LT ENGINE FAILED ABOUT 10-15 MINUTES INTO FLIGHT AT FL190. THE CREW REPORTED HEARING A BOOM AND THE 1ST OFFICER NOTICED THE LT ENGINE ROLL BACK. AN AIR START WAS NOT ATTEMPTED AND THE ACFT DIVERTED. REPLACED EEC WITH REPAIRED UNIT. PERFORMED GROUND RUNS AND THE TEST FLIGHT. ACFT RETURNED TO SERVICE. MFG SUSPECTS ONE CHANNEL OF THE EEC DEVELOPED A FAULT AND ATTEMPTED TO CHANGE CHANNEL. THE EEC HAS A LANE-CHANGE RELAY, WHICH IS AN ELECTROMECHANICAL RELAY (AND NOT A SOLID STATE RELAY AS IN THE NEWER EEC`S) WHICH HAS A TENDENCY TO STICK OR TOO SLOW TO SWITCH CONTACTS. WHEN THIS TYPE OF FAILURE OCCURS NEITHER CHANNEL IS IN CONTROL OF THE FUEL FLOW AND FLAMEOUT WILL OCCUR. THIS TYPE OF FAILURE WILL GENERATE A 4C CODE WHICH WAS OBSERVED ON THIS ENGINE. (K)