What was found
UPPER FUSELAGE, MAIN CARGO COMPARTMENT, DURING ELT SYSTEM TEST FOUND ELT UNIT SHOWING 3 FLASHES FAULT CODE.(<P>PERFORMED T/S AND FOUND ELT SYSTEM ANTENNA INTERNAL IMPEDANCE OUT OF RANGE AND ELT UNIT DISPLAYING INCORRECT A/C'S REGISTRATION NUMBER REPLACED AND TESTED ELT UNIT AND ANTENNA I/A/W B737-800 AMM REV:50 DATED 15/FEB/23. TASKS: 23-24-00-000-801, 23-24-00-400-801, 23-24-01-000-802 AND 23-24-01-400-802. SATISFACTORY CONDITION </P>)