The logic box (buzzer) is located under the dash on the drivers side. In order for the logic box to activate (buzz) 1. You must have the key in the ignition. & 2. The door must be open. On the drivers side you'll notice 2 seperate switches on the door. The top one is for the door lights, and the bottom is to turn the logic box on. It's possible that a previous owner may have disconnected this switch. It buzzes every time to door is open, and it is not a pleaseant sound. But after all it is there to remind you not to leave your keys in the ignition... -Robert vin 6585 (The DeLorean from hell.)