What was found
APU FIRE WARNING INTERMITTANT, DISCHARGED 2 BOTTLES TO APU. CHECKED CURRENT FAULTS AND FAULT REVIEW, FOUND NO CURRENT FAULTS AND ONLY LEG-47 FAULT (CFDIU COMM FAULT) STORED. PERFORMED FDCU R-T-S TEST FOR APU, TEST PASSED. CHECKED LOOP A AND LOOP B RESISTANCE FROM FDCU CONNECTORS, LOOP A 1456 OHMS AND LOOP B 1460 OHMS. INSPECTED APU FIRE DETECTORS VISUALLY, NO ABNORMALITIES NOTED IAW FIM 26-12, WDM 26-12-01 AND SSM 26-12-0. PART 03. FOUND FIRE CONTROL PANEL CORRODED COMPONENTS, APU FIRE WARNING LIGHT (L2-130) AND APU OFF/AGENT ARM SWITCH (S1-387). REPLACE BOTH COMPONENTS IAW WDM 26-12-01, 26-12-02 AND TECH TIP 17-0025. REMOVED AND REPLACED APU FIRE WARNING LIGHT (L2-130) AND APU OFF/AGENT ARM SWITCH (S1-387) THEN PERFORMED APU FIRE LIGHT TEST OF THE GROUND CONTROL PANEL, TEST SATISFIED IAW WDM 26-12-01, WDM 26-12-02, AMM 26-21-10-4, AND AMM 26-21-10-5.