What was found
FIRE WHEEL WELL. PER FIM 26-17 801. CHECKED WIRING FOR DAMAGE, CHAFFING, AND CORROSION. NO DEFECTS NOTED. CHECKED FOR CONTINUITY AT PIN 10 OF RELAY TO GROUND, FOUND CONTINUITY. REPLACED RELAY IAW BSWPM 20-81-22, NO HELP. THIS ITEM IS TRANSFERRED TO DMI 71300179 CAT "C" DUE DATE 12 SEPT 2020 (M). PROCEDURES C/W IAW MEL 26-17-1B, PLACARDS INSTALLED. REF DMI # 71300179 WHEEL WELL FIRE DETECTION SYSTEM INOP. PERFORMED RESISTANCE CHECK BETWEEN CONNECTOR DM694B & DM694A IAW B747-400 WDM 26-17-11. FOUND SHORT TO GROUND ON M694B FIRE DETECTOR. REMOVED AND REPLACED M694B FIRE DETECTOR IAW B747-400 AMM 26-17-02. OPS CHECK GOOD IAW B747-400 AMM 26-17-00, NO DEFECTS NOTED, THIS DMI IS CLEARED. ALL PLACARDS REMOVED.