Q: Headlights automatically turn on by themselves at night when the car is off

asked by on January 02, 2017

My 2004 Chevy Trailblazers headlights, turn on automatically at night while parked in the driveway, after about 5 to 10 minutes of the car being off, the headlights automatically come on. They do not turn off until the battery dies! I tried messing with the switch, and when the headlights turn on, it won't even let you turn the lights off with the switch, after about 3 minutes it will let you turn them off. But after you go back inside for a few, they turn right back on. If it matters, I did get aftermarket light bulbs a couple months ago. But the problem didn't start until last month. Thanks for the assistance!

My car has 174000 miles.
My car has an automatic transmission.

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Hello, thank you for writing in. The vehicle may be having issues with the headlight circuitry. This may mean that the sensor, photocell, body control module, replacement headlight, or a fuse/relay has failed. Something is allowing power to be sent to the headlights when the vehicle should be off. One of the quickest way to track down the culprit is to use a voltmeter to trace the power supply when the issue is occurring. This part is important! Do not try and diagnose the issue when the issue is not currently present. Wait and catch it in the act, and then perform the voltage tests. These can be done at home with a voltmeter if you are equipped. If not, contact our service department to schedule an appointment.

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