Q: Low beam headlights won't work on 2002 Chevrolet Trailblazer

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My low beam headlights won't turn on, have tried to check fuses and bulbs, everything is still good. But after a day and a half they turned on again. Took it to a dealership said it could be electrical, sure don't want to pay just for them to look at it. So is there anythin I can do on my side that maybe i can fix on my own? As I am speaking the headlights are working, but I just want to make sure they won't turn off again, how do I check to make sure they won't go out again?
(1) Answer
Look in your owner's manual in the glove box and determine whether your headlights are controlled by relays which should be under the hood in a "fuse and relay box." If the relays aren't labeled, you can find the ones for the headlights by having someone in the car flicking the hi-beam switch high and low and you feeling for the relays that are clicking when the switch is flicked. If you can locate the relays that way, you may be able to swap them and have the problem reverse itself. You could determine which relay is failing and fix your car pretty cheap that way.