This is a wiring diagram for a headlight reminder to tell you that you have left your lights on when you turn your ignition switch off. It costs less than $10.00, is easy to make, and very effective. It requires an automotive relay, readily available at automotive supply stores and a 12 volt pezio buzzer from Radio Shack. You can buy a complete reminder, ready to install, on eBay or an automotive supply store for $25 to $50 if you do not want to assemble one.
The wire going to post #30 attaches to a fuse that only has power when the lights are on. I hooked it to the parking light fuse, since it is powered when the parking lights or the headlights are on.
The wire going to post #85 attaches to a fuse that only has power when the ignition switch is on.
A wire from post #86 goes to ground and #87A goes to the buzzer.
The 3rd buzzer wire goes to ground. I just taped up the bare wires and connections on the relay and the buzzer and hung it up using a zip tie.
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