This guide provides comprehensive instructions for adjusting your B8 S4 headlights using VCDS (VAG-COM). Whether you need minor adjustments or a full reset, this guide covers both scenarios, ensuring your headlights are aimed correctly and functioning optimally. This is especially helpful for lowered cars where the factory adaptive bi-xenon headlights might not illuminate the road sufficiently.
Part 1: Minor Headlight Adjustments (No VCDS Required)
This method is ideal for small adjustments when your headlights are generally aligned but need slight tweaking.
Tools:
- Phillips head screwdriver
Time:
- Approximately 5 minutes
Procedure:
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Park and Prepare: Park on a level surface about 20 feet from a wall or garage door, preferably in a dimly lit area.
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Access Adjusters: Open the hood and locate the headlight adjusters. They’re usually behind dust covers that can be easily removed. See image below for reference. The red circles indicate the VERTICAL adjusters, and the yellow boxes indicate the LATERAL adjusters.
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Turn on Headlights: Turn on your headlights without starting the engine.
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Adjust Vertically: Cover one headlight to focus on the other. Using the Phillips head screwdriver, slowly turn the vertical adjuster. Clockwise raises the beam, counterclockwise lowers it. Aim for a downward angle of approximately 1.5 degrees, meaning the beam should be about 0.5 inches lower at 20 feet. Focus on the lower cutoff of the beam to avoid blinding oncoming traffic. See the image below for proper aiming reference.
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Repeat for Other Side: Repeat the adjustment process for the other headlight.
Part 2: Resetting Headlight Adaptation with VCDS
This method is necessary for significant adjustments, when replacing a ballast, or if you have a “Dipped Headlight” error on your dashboard. It involves resetting the headlights to factory settings and then recalibrating them.
Tools:
- Phillips head screwdriver
- Laptop/Tablet/PC with VCDS software installed
- VAG-COM diagnostic cable
Time:
- Approximately 15 minutes
Procedure:
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Prepare Your Vehicle: For significantly lowered cars, raise all four wheels off the ground to simulate stock ride height. This prevents the suspension sensors from interfering with the calibration process. If your vehicle has air ride, this step is not necessary.
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Connect VCDS: Connect the VAG-COM cable to your car’s OBD-II port and launch the VCDS software on your computer.
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Access Xenon Range Controller: Select “Select Control Module,” then choose “55-Xenon Range.”
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Reset to Factory Defaults: Go to “Adaptation – 10,” enter channel 00, and click “Read.” This will load the factory default settings. Click “Save” to apply the reset.
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Basic Settings Adjustment: Go to “Basic Settings – 04” and click “Go!” The software will guide you through the adjustment process. Wait for the output to display “ADJUST” or “LEARNING.”
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Manually Adjust: While VCDS is in “LEARNING” mode, manually fine-tune your headlight vertical aim using the adjusters as described in Part 1. If you already adjusted them to your liking in Part 1, simply wait 20-30 seconds for the module to learn the current positions.
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Confirm Adjustment: Click “On/Off/Next” in VCDS. The output should indicate successful adjustment. Double-check for fault codes to confirm the process was completed successfully. You should see a screen like this:
Conclusion
By following this comprehensive guide, you can successfully adjust your B8 S4 headlights for optimal performance and visibility. Whether you prefer the quick manual adjustment or need to perform a full reset with VCDS, this guide provides the steps necessary to achieve proper headlight alignment and eliminate any related fault codes. Remember to always prioritize safety and ensure your adjustments do not blind oncoming traffic.
