headlight wiring diagram

2009 LINCOLN MKZ
78 MILES • 3.5L • V6 • AUTOMATIC
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DGRAVES
Low beam passenger headlight went out, replaced bulb and ballast and the fuses and relays are good. Why is the light still not working?
Jan 13, 2019 at 12:46 PM
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BMDOUBLE
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One quick thing to try is to disconnect your battery for one minute and reconnect. The modules in these vehicles have protect circuits that will disable a particular circuit if there is an issue. A reset sometimes will restore operation so long as there is no more issues on said circuit.
Jan 13, 2019 at 4:00 PM
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STRAILER
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Hello,
I agree with BMDOUBLE the smart junction box could be having troubles, if resetting it doesn't work let's confirm the failure by testing the power at the fuses. Here is a guide to help and the fuse locations with the headlight wiring diagrams so you can see how the system works:

https://www.2carpros.com/articles/how-to-check-a-car-fuse

If the smart junction box is bad you can replace it because it self initializes. Check out the diagrams (below) check for power at fuses # f19, f2 and f24. Please let us know what you find. We are interested to see what it is.
Jan 13, 2019 at 5:33 PM
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PECCHE20
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My driver side low beam went out. It is a hid system. I checked the fuses, replaced the hid bulb and it still does not work. I am assuming it is the ballast?... how do I remove the head light assembly to get to this?
Apr 26, 2020 at 11:17 AM (Merged)
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MLDANIELS2000
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Most likely bad ballast.

Removing headlight:
1.Remove the front bumper cover. For additional information, refer to BUMPERS .
2.Remove the headlamp assembly pin-type retainer.
3.Remove the 4 bolts and the headlamp assembly. Disconnect the electrical connectors.
4.To install, reverse the removal procedure

Removing bumper cover:
2.Remove the 6 pin-type retainers (3 each side).
3.Remove the 8 fender splash shield screws (4 each side).
4.Remove the 4 air deflector bolts.
5.If equipped, disconnect the fog lamp electrical connectors.
6.Remove the 5 bolts from the top of the radiator grille.
Apr 26, 2020 at 11:17 AM (Merged)
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CITATIONMAN
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Thanks for the instructions; worked like a charm. I paid 55 bucks apiece online (I did both even though only one was out). Could not have been more straightforward. The dealer wanted 150 bucks each and estimated 3 hours. I saved 500 bucks with DIY
Apr 26, 2020 at 11:17 AM (Merged)
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OLIVE09
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I currently have HID headlights and I want to know how to convert it to halogen or can I do that?
Apr 26, 2020 at 11:17 AM (Merged)
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WRENCHTECH
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That would be way more hassle that it would be worth. The car is wired for the HID modules and igniters.
Apr 26, 2020 at 11:17 AM (Merged)
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OLIVE09
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I cannot find a headlight assembly because mine is cracked so I thought it would be easier to convert it. Where do you suggest I look for an assembly at besides Ford?
Apr 26, 2020 at 11:17 AM (Merged)
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WRENCHTECH
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ford is the best place to get the parts.
Apr 26, 2020 at 11:17 AM (Merged)
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