do not replace anything yet ! first check the electrical system . disconnect the negative cable ,$ |1 g. `: u$ p
connect a test light between cable and battery post . if the test light lights up bright , there could be a short circuit somewhere . pull out each fuse to see until the test light goes dim , 4 q* R( R) X0 k9 B' k$ M! _, m4 [now you know in which that device is draining the battery .