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Q: Headlights wouldn't turn off / now they won't turn on

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When I turned off the car and he lights I noticed my headlights would not turn off. My friend checked under the hood and unplugged the wires seeming to connect the power lights to a battery. They turned off - which was good cause otherwise it would mean I would need to jumpstart. After they turned off we attempted to restart the car, turn on the lights and everything but the headlights turned on. What should I do?

My car has 240000 miles.
My car has an automatic transmission.

The most likely components to cause this may be the headlight relay, headlight switch, or the ignition switch itself. The relay is an electro-mechanical switch. The headlight switch sends a power signal to it. It then switches on internally to send power to the headlights. If the relay is sticking either in the on or off position, this can cause the lights to stay on or not turn on. If the headlight switch has failed, it may not be signaling the relay properly. With the ignition switch, if the mechanical tumbler portion is worn, it may not be fully moving it’s internals to signal the electrical portion of the switch to turn the lights on or off. Or vice versa, the electrical portion of the switch may have shorted internally.

Since one or more components may be at fault, it may be best to have a certified technician properly diagnose why the headlights are not working to find the exact cause.

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