What was found
LANDING GEAR WARNING SOUNDED WITH GEAR DOWN AND LOCKED AND THREE GREEN. WARNING HORN COULD NOT BE SILENCED. REPLACED PSEU PER AMM AND CENTRAL AURAL WARNING COMPUTER AFT JACKING A/C AND FAILURE TO DUPLICATE. BOTH REQUIRE CHECKOUT RAN AUTO-SELF TEST OF PSEU PER AMM. CHECKS GOOD WITH NO FAULTS. C/W ADJ/TEST OF CENTRAL AURAL WARNING UNIT PER AMM. ALL MODES CHECK GOOD. SWUNG GEAR NUMEROUS TIMES AT VARIOUS L FLAP SETTINGS. UNABLE TO DUPLICATE LANDING GEAR WARNING INDICATION. SYSTEM CHECKS GOOD. OK FOR SVC.