meitetsu

I just purchased a RX300 that keeps blowing 7.5 amp Fuse (position 44 on fuse block). This is fuse for Radio and HVAC Control button lights as well as the shift selector. As soon as you replace fuse and turn IG ON it blows immediately. I see on the internet that several people have had this problem, but never see anyone post any solutions. I'm sure it's probably a short but not sure exactly where. Anyone ever had this problem and found the solution? I appreciate any help. Thanks.