do not replace anything yet ! first check the electrical system . disconnect the negative cable ,) r; c L% Z+ e- I5 w# n. S/ _
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 ,; p8 t2 d& U9 t$ P
now you know in which that device is draining the battery .