Audi A4 B7 US Lights VCDS Modification: Disabling Parking Lights

Are you looking to modify the front lighting on your Audi A4 B7 with US-spec headlights using VCDS? One common desire is to disable the parking lights that illuminate with the headlights while retaining turn signal functionality. This guide explores how to achieve this modification using VCDS.

Understanding the Audi A4 B7 Lighting System with VCDS

The Audi A4 B7 lighting system is controlled by the Body Control Module (BCM), which can be accessed and modified using VCDS (VAG-COM Diagnostic System). Within the BCM, lighting functions are managed through “Leuchte” programming, which defines how individual lights behave in different scenarios. Each light has a specific “Leuchte-set” that dictates its various functions and dimming levels.

This modification focuses on isolating and adjusting the parking light function within the larger Leuchte-sets that control the front turn signals/parking lights combination in US-spec headlights.

Identifying the Correct Leuchte-Sets

Based on an analysis of a similar vehicle’s BCM adaptation map, the relevant Leuchte-sets for the front parking/turn signal lights are likely:

• Leuchte2SL VLB10 (Left-side lamp)
• Leuchte3SL VRB21 (Right-side lamp)

These Leuchte-sets typically control four main functions:

1. Parking Lights: Illumination at approximately 30% brightness.
2. Coming Home/Leaving Home: Illumination at approximately 30% brightness.
3. Daytime Running Lights (DRL): Illumination at 100% brightness.
4. Turn Signals: Flashing functionality.

Disabling the Parking Lights with VCDS

The key to disabling the parking lights without affecting other functions lies in adjusting the dimming level associated with the parking light function within the respective Leuchte-sets. To do this:

1. Connect VCDS to your vehicle’s OBD-II port.
2. Access the BCM module.
3. Navigate to the Adaptation channels.
4. Locate the following adaptation channels:
   • (6)-Leuchte2SL VLB10-Dimmwert AB 2 (Left parking light dimming)
   • (6)-Leuchte3SL VRB21-Dimmwert AB 3 (Right parking light dimming)
5. Change the value of both channels from 30 (or the current dimming value) to 0. This sets the dimming level for the parking light function to 0%, effectively disabling them.

Important Considerations

• Backup your existing BCM coding before making any changes. This allows you to revert to the original settings if needed.
• These instructions are based on analysis of a similar vehicle and may not be directly applicable to all Audi A4 B7 models. Consulting a detailed wiring diagram or your vehicle’s specific adaptation map is highly recommended.
• This modification will only disable the parking light function. The turn signals, DRLs, and Coming Home/Leaving Home functions will remain unaffected.

Conclusion

Disabling the parking lights on an Audi A4 B7 with US-spec headlights can be achieved using VCDS by adjusting specific adaptation channels within the BCM. This modification allows for a customized lighting configuration without compromising other essential functionalities. Remember to proceed cautiously, back up your existing coding, and consult reliable resources for your specific vehicle model.