Both the low beam and high beam headlights are not working?

2008 CHEVROLET IMPALA
173,694 MILES • 3.9L • 6 CYL • 2WD • AUTOMATIC
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MVANN74
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Bulbs are good. Fuses are good. Daytime running lights and fog lights work. Removed headlight assembly to test power and ground. I have power on both pins on both sides. Could this possibly be a grounding issue? If so, where do I find the ground for headlights?
Dec 9, 2023 at 11:00 PM
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JACOBANDNICKOLAS
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Hi,

I attached the wiring schematic below. If the high beam works, the ground is good. That leaves a power supply which you indicated is present.

So, check the light socket and make sure it isn't corroded or damaged. Also, are you certain the bulbs are good?

Let me know.

Take care,

joe

See pics below.
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Dec 9, 2023 at 11:40 PM
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MVANN74
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Thanks for wiring schematic. High beams do not work. No corrosion or damage in either socket. The only lights that work are the DRL and the fog lights. No low or high beam. Bulbs are good. Fuses are good. Although I was reading something about a non serviceable relay on underside of fuse block. Some kind of circuit board. If that's the case will the entire fuse block need to be replaced?
Dec 10, 2023 at 12:19 AM
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JACOBANDNICKOLAS
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Hi,

That is correct. There is a high and a low beam relay that is part of a printed circuit board and non-serviceable.

If you look at the schematic I sent, it indicates PCB, which is a printed circuit board. I have no idea why they do these things.

Let me know.

Joe
Dec 10, 2023 at 7:33 PM