after shuting off my truck (94 Bronco) and taking the key out the warning buzzer will continually sound until I shut the door (like I left the lights on or the key in the ignition). Thinking it was the ignition I but a new ignition in (key). Thats not it. Any idea what else to check? I'v grown use to the sound but have left my lights on several times, I would like to fix before I kill the battery.