disabling factory alarm horn when setting alarm
 

Hello I'm a new member, I just purchased a used 00 4runner, does anyone know how to disable the horn from beeping when activating and deactivating the factory alarm using the factory keyless remote. The owners manual says it can be done and to call the dealer. I've tried calling 2 dealers 1 said they don't know anything about this and would need to see the car. the other did not come back to the phone after being on hold for 15 minutes..
thanks for any advise...