I recently purchased and 05 coupe with Bose and navigation. And after trying to wire a new radio(it already had and aftermarket one) the radio fuse keeps blowing, even with the radio unplugged and keys out of the ignition. I think a key detail is that the previous owner appears to have had an aftermarket sub and amp that they removed prior to selling the car. Any help would be greatly appreciated as stereo wiring is not something I have attempting before. Thanks!

 

Here is the FSM for your '05 coupe's stock audio system:
https://www.nicoclub.com/service-man...F2005%2Fav.pdf
Scroll down below the "viewing window" on that page and you can "Click here to download a copy".

And here is the Power Supply, Ground, & Circuit Elements book:
https://www.nicoclub.com/service-man...F2005%2Fpg.pdf
Same advice for downloading the pdf copy.

Those books will show you the original wiring (be sure you're looking in the "w/Bose" section of the AV book). Maybe you will find the previous owner tapped off of the "live" power and when they removed their rig they left that wire in a position where it's shorting. You'll find it!