If this is an after market system, it could be anywhere. For factory units, close all doors and use the key to lock and unlock driver door. If it fails, try the passenger door. Turning the key to ON in ignition should disarm the system.
Nov 15, 2012 at 7:19 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.