I'm stumped with this radio issue
 

Hi all, first time posting. I have a 2004 4wd 4dr blazer. When I bought it a couple years ago, the radio would not work with the ignition in accessory, and it would not stay on after the engine shut off. It has the double din 6 disc cd changer. Now, the power windows do work with the key in accessory, so I am thinking the ignition switch is good.

I tried installing an aftermarket cheapo head unit thinking that the cd player was messed up, well there is no acc. wire at the headunit, so I went and bought the module adapter that communicates with the bcm, and the new radio still would not work in accessory, so I'm leaning towards BCM. Has anyone else ran into a situation like this?

*side note* I have a 2001 blazer I just bought as a donor vehicle for a new hood and fender, the radio works fine in that one, but it's a 1.5 din single cd, and I don't think it's controlled by the bcm for accessory power.