How do I disable Onstar on 2019 New Generation GMC Sierra

Find the module and disconnect it. Look around on the web for the location.

Yup I kind of know where it is in the Center Radio stack! However new gen console block easy access to the bottom stack screw cover between the stack and console! I guess the real question at this point is , how do you pull that cover. I just highly doubt a service person would have to remove the console . Given that would entail removing both front seats. See attached photo of lower Center stack trim Awaiting on input as I have tried trim tools with no available. Pros there a special tool to release that trim piece which wraps around the lower Center stack above the console that conceals the 2 lower Center stack torx screws.

Im having a hard time removing the radio I’m almost there but I can’t get the bottom loose exactly where your pic is showing how did you do it

There is a maroon plug up around the gas pedal area. This is the antenna coax for the gps and cellular that connects to Onstar. Takes about 30 seconds to unhook.

That was easy! Look under the dash by the gas pedal you find a square maroon colored connector. This is the coax cable for Onstar. Pull off by pressing the tab on one side and pull straight down (took a little effort). The Onstar button went from a green light to a red light.

Thank you for the photo Dan19LTZ, makes finding it much easier. I however have a 2021 silverado and the one thing that was different from the photo above is that their is an orange lock (so to speak) that you have to pull straight down then press the tab and pull it straight down. I've had issues with onstar interfering with my sxm radio audio, so maybe this will put a stop to this issue since Chevrolet has no fix as of right now.