I just want the onstar disabled.

The OnStar system is integrated into the Telematics Communication Interface Control Module (TCICM) as well as the Human Machine Interface Control Module (HMICM). The TCICM is powered by the Air Bag/Info Fuse (10A). The HMICM is powered by the RDO Fuse (20A). Both fuses can be found in the right instrument panel fuse box which is located in the right end of the dash. You can read about how to disable OnStar here: https://www.yourmechanic.com/article/how-to-disable-onstar-by-elan-mcafee

How to Deactivate Onstar

Go under the hood and remove the cover for the underhood fuse and relay box, look under the lid, it shows a fuse diagram. pull the fuse that is described as "Communication" or maybe just "COMM" for short not sure about abbrieviations they use on GM cars and trucks

Here's a link on removing onstar. Disabling Onstar

You have to call Onstar to cancel service. If you try to disable it,your car wont start.

The OnStar module is located under the right rear passenger seat, unhook the connector. Also, fuse #27 in the rear fuse panel is for the OnStar, but the DVD player as well.

OnStar fuse is on the inside cabin fuse box, 10amo fuse. Fuse box is usually located on drivers side, near your left knee.

Unplugging the Onstar unit should deactivate it and if you can get to it. I haven’t yet taken the time to locate the Onstar unit in my Yukon. In older Yukons, Tahoes, and Suburbans the Onstar was in the cargo area, above and behind the right rear wheel well. However, it’s my understanding that when they redesigned the Onstar unit for smaller size, they started putting it behind the instrument cluster in the dashboard. Good luck

The OnStar module is under the rear seat, passenger side. You should be able to just pull the connectors out of the module. Just the rectangular ones.

The dealer is thinking about the power amplifier for the Bose radio system. That's in the fender at the right rear of the car, but that's not the issue here.

you can remove the fuse however you will get a call asking if everything is okay.