Headlight Assembly replacement issue?

2013 AUDI A4
170,000 MILES • TURBO • 2WD • AUTOMATIC
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C SILVER
Just replaced the driver side headlight assembly for the vehicle listed above 2T 4 door. Also replaced the bulb. Everything works except for the headlight beam. Tried a second new bulb. Nothing. Fuses appear to be good. What do you suggest?
Jun 13, 2025 at 7:51 PM
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STRAILER
  • ✓ASE Certified Mechanic
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  • ASE Certified Mechanic
Does this car have the HID's? If not, I would test the yel/blk wire for power with the headlights on. This guide can help you:

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

If you don't have power, then you have a bad vehicle electrical system control module. Here are the wiring diagrams so you can see how the system works. Check out the images (below). Please let us know what happens.
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Jun 14, 2025 at 9:06 AM
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