How do you disable alarm on 2003 Mitsubishi montero?

To disable the alarm on a 2003 Mitsubishi Montero, insert the key into the driver's door lock and turn it to the unlock position. This should deactivate the alarm system. If that doesn't work, you can also try starting the vehicle with the key, as this generally resets the alarm. For persistent issues, consult the owner's manual or a professional for assistance.