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Audi Xenon HID Ballast 8K0941597B 4G0907397D for D3S D3R D4S D4R

Audi Xenon HID Ballast 8K0941597B 4G0907397D for D3S D3R D4S D4R

SKU: NLT1M01342
$38.99 In Stock
$38.99
Sale price  $38.99 Regular price 
Ships for free in 2–4 business days.
This new aftermarket 12V/35W xenon HID ballast replaces 8K0941597B, 4G0907397D, and the listed interchanges on compatible Audi factory D3S, D3R, D4S, or D4R headlamps.
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Compatible Models

We do our best to list all compatible models. Although this may be the part you need, your exact model may not appear below.

Compatible equipment / model
  • Audi A1 / S1 — 2010-2017 with matching factory xenon module
  • Audi A3 / S3 — 2009-2016 with matching factory xenon module
  • Audi A4 / S4 / A4 Allroad — 2010-2016 with matching factory xenon module
  • Audi A5 / S5 / RS5 — 2008-2017 with matching factory xenon module
  • Audi A6 / S6 / RS6 / A6 Allroad — 2010-2015 with matching factory xenon module
  • Audi A7 / S7 / RS7 — 2010-2015 with matching factory xenon module
  • Audi A8 / S8 / A8L — 2010-2014 with matching factory xenon module
  • Audi Q3 — 2012-2015 with matching factory xenon module
  • Audi Q5 / SQ5 — 2008-2017 with matching factory xenon module
  • Audi Q7 — 2010-2015 with matching factory xenon module

Product Overview

When a factory xenon lamp flickers, shuts down after warming up, or will not strike with a known-good bulb, the ballast becomes a likely repair point. The stamped module number matters more than the Audi badge or model year alone.

The ballast starts and regulates the HID bulb. Audi used multiple halogen, xenon, adaptive, and LED systems across these years, so the original module is the best reference.

Key Features & Performance

  • Regulates compatible factory HID bulbs
  • Services the external module separately
  • Useful for a verified ballast or moisture failure

Replaces Part Numbers

  • 8K0941597B
  • 8K0941597C
  • 8K0941597E
  • 4G0907397D
  • 4G0907397P
  • 4G0907397R
  • 4G0907697D
  • BAM92-143700
  • W003T20171
  • W003T22071

Common Uses

  • Repairing a xenon lamp that goes dark
  • Replacing a water-damaged ballast after sealing the housing
  • Testing a suspected ballast on an identical side-to-side system

Technical Specifications

  • Product Type: Xenon HID ballast / control unit
  • Voltage: 12V
  • Power: 35W
  • Supported Bulbs: D3S, D3R, D4S, D4R as listed
  • Placement: Front left or right headlamp
  • Lighting System: Factory xenon/HID only
  • Condition: New aftermarket replacement

Installation & Fitment

  • Disconnect power and allow high voltage to discharge
  • Confirm HID/xenon equipment
  • Match every number and connector
  • Repair moisture entry and transfer seals
  • Test operation and perform coding if required

Compatibility Notice

Northline Parts does its best to list all known compatible models, but the correct part may fit an application not shown.

Audi used several halogen, xenon, adaptive, and LED systems within the same model year. Order only when the complete ballast number, D3/D4 bulb family, connector, mounting pattern, and headlamp label match.

Frequently Asked Questions

Q: Which number is the best fitment check? A: Use the complete number printed on the original ballast. Model and year alone are not enough because Audi offered several headlight systems.

Q: Does this work with halogen or full-LED headlights? A: No. It is for a compatible factory xenon/HID assembly using the listed ballast and bulb family.

Q: Can it fit either side? A: The researched listing identifies front left or right use when the module number and mounting pattern match.

Q: Can a bad bulb look like a failed ballast? A: Yes. Test the bulb, wiring, power, ground, and moisture condition before replacing the control unit.

Part Summary

keywords: 8K0941597B xenon ballast replacement, 4G0907397D Audi HID module, D3S D3R D4S D4R ballast, Audi headlight flickering repair, aftermarket Audi xenon control unit

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