Tom_Slick

Since my 2006 now longer works with OnStar(outdated cell connection) I plan on removing the fuse… I also recently added an aftermarket stereo… My car is a 3LT that came with the Bose/ Nav/ XM radio… I’d like to remove the XM box also, and I assume there is a separate fuse for that also…? If so, I want to remove it too.

4SUMERZ

Unfortunately, the XM is on the same circuit as the radio.(RADIO/S-BAND/VICS) 15A fuse.

You can remove the fuse for the OnStar, which is a usual suspect for parasitic draw.
If you have a digital multi-meter, you can hook it up at your battery and check before/aft the draw of the On-Star.

Tom_Slick

Thanks again... After pulling the fuse, and going for a drive with my lights, A/C, radio, and front bumper camera on, I noticed that the voltage seldom dropped below 14.0. Prior to pulling the fuse I’ve seen it drop as low as 13.0 when under a load. I’ve bought multiple batteries, changed the battery terminals thinking that would fix the problem in the past, it didn’t… The funny part is that even though I paid a monthly fee for OnStar for many years, I seldom ever used it.