Q: Both R&L low beam headlights quit working simultaneously.

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Both R&L low beam headlights quit working. All related fuses are OK. Replaced both low beam lamps 1.5 years ago with great results. Replaced the low beam relay and that did not work. The high beam lights work correctly. All other lights on the car work correctly. No "burnt" electrical smells. Don't know how to check to see if the replacement low beam headlamps are still good other than to remove and visually inspect the filaments? Thanks.

My car has 130000 miles.
My car has an automatic transmission.

Hi there. Check the switch to the headlights and see if there is a break in the wiring. Check the fuses and see if there is any fuse that are blown. If the fuses are good and there is no break in the wiring, then either the switch has failed or the ballast resister has failed on the low beam circuit. Turn on the switch and check for power coming out of the switch. If there is power to the switch and power out of the switch, then I recommend replacing the ballast resister. If there is no power coming out of the switch, then the switch needs replaced. If you need further assistance with diagnosing the low beams, then seek out a professional, such as one from Your Mechanic, to help you.

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