What was found
RED CONFIG LIGHT AND GEAR NOT DOWN EICAS MESSAGE DISPLAYED WITH NO ASSOCIATED SIREN STARTING AT TOP OF DESCENT WITH IDLE POWER. THROUGHOUT THE DESCENT ANY TIME IDLE POWER WAS APPLIED THE LIGHT WOULD RE-APPEAR AND WOULD GO AWAY IF MORE THAN IDLE POWER WAS APPLIED. ONCE THE FLAPS WERE SELECTED TO FLAPS 1 ANY IDLE POWER SITUATION RE-LIT THE LIGHTS AND MADE THE SIREN SOUND AS WELL. ONCE THE GEAR WAS DOWN ALL LIGHT AND SIREN ACTIVATIONS WENT AWAY. REMOVED AND REPLACED LANDING CONFIG WARNING MODULE CARD (M983) FROM THE WARNING ELECTRONICS UNIT (WEU) ON P51 PANEL PER ABOVE REFERENCE. OPS CHECKED SATISFACTORY.