What was found
AT T/O, NOSE STRUT EXTENSION EVERYTHING NORMAL HAD AURAL FIRE WARNING BELL ON BOTH OVERHEAD SPEAKERS WITH NO OTHER INDICATIONS. LIGHTS TESTED NORMAL. BELL WENT OUT WHEN BOTH OVERHEAD SPKR C/B'S PULLED. UNEVENTFUL RETURN. PERFORMED PSEU BITE IAW FIM 32-09-03/101. NO FAULTS FOUND. PERFORMED EICAS BITE IAW FIM 31-41-00/101. NO FAULTS FOUND. PERFORMED AIR/GROUND SYS MX PRACTICES IAW AMM 32-09-02-2-0 (PUT ACFT IN AIR MODE). COULD NOT DUPLICATE WARNINGS. PERFORMED TEST OF AURAL WARNING IAW FIM 31-51-00, FIG 104. NO FAULTS FOUND. REQUIRES FURTHER T/S. PUT A/C INTO AIR MODE AND PERFORMED TESTS OF FIRE WARNING SYS AND WEU TESTS. ALL TESTS WERE SAT. WEU POWER SUPPLIES HAVE NO FAULTS. RESTORED A/C TO GROUND MODE. R & R WEU MODULES - M619 RT SIREN/OWL MODULE, M999 LT SIREN/OWL MODULE, AND M1000 BELL/CHIME MODULE IAW AMM 31-51-04-4. PERFORMED ALL TESTS OF WEU CARD FILE IAW AMM 31-51-04 WITH SAT RESULTS.