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Q: Headlights come on when off in middle of night draining battery

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My headlights mysteriously power on in the middle of the night without any key in the ignition or it started and drains my battery about every night almost for a week now. I'm not sure what is going on. Is it a fuse or relay? Is it my turn signal switch and corrosion?? Help please. Tina Daniels

My car has 167834 miles.
My car has an automatic transmission.

A: There are several possibilities that may be...

There are several possibilities that may be the source of this issue - first make sure your headlight switch is in the "Off" position (rather than "Auto" for example). Then remove both the headlight relay and the daytime running light (DRL) relay from the fuse panel. Leave the vehicle overnight to see if the lights come on. If not - progress! Re-install the DRL and headlight relays one at a time - install, leave overnight, check to see if the lights come on. Reinstalling either the DRL or headlight relay causing the lights to come on will identify which of these relays has burned contacts, and is sticking in the "On" position. If you need assistance in diagnosing this issue, a YourMechanic certified technician can come to your location to inspect your vehicle and help find the faulty electrical component.

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