I have a 2021 LT and I was able to turn off the horn blaring when the car is turned off and the remote is left in the car. Home Screen/Settings/Vehicle/Remote Lock Unlock and Start/Remote Left in VehicleThere's no way to disable that which works. I recall a "Remote Left in Vehicle Alert" from page 149 of https://my.gm.ca/content/dam/gmowne...?evar25=ch_bolt-recall_owners-manuals_bolt-ev. I've shut that off already and checked it. It doesn't help. Have gone thru this many times (e.g. checking that the setting is off and turn it on then exiting then back off then exiting)
If you know of a setting that works, let me know.
I don't recall the exact repro steps but it's along the lines of with fob in pocket, turn off car. Exit car via driver's door and maybe close it (don't lock anything and I don't have passive locking or unlocking enabled). Re-enter from driver's side w/fob in pocket. Upon closing driver's door you may get the triple quick braps of the horn.