Answer
Jan 23, 2025 - 12:29 PM
If you're getting an automatic headlight adjustment defect warning on your BMW 428i, it usually points to an issue with the headlight leveling system. The most common causes are:
- Faulty Level Sensors – These are mounted on the front and rear suspension arms and tell the system how the car is sitting. If one fails or gets damaged (often due to corrosion or a broken linkage), the system won’t adjust properly.
- Disconnected or Damaged Wiring – Check the connectors going to the level sensors and headlight control module. A loose or corroded connection can trigger the warning.
- Failed Headlight Control Module (LCM or FRM) – The Footwell Module (FRM) controls lighting functions, including auto-leveling. A fault here can prevent the system from working.
- Coding or Calibration Issue – If the headlights were replaced, the system may need to be recalibrated using BMW ISTA software or a high-end scan tool.
- Faulty Adaptive Headlights (if equipped) – If your car has Adaptive LED or Xenon lights, a motor failure inside the headlight can cause the system to register an adjustment defect.
In any case, the OEM manual should contain every manufacturer-provided troubleshooting procedure to make sure you know exactly what's the issue.
Good luck!
