Enabling BMW Rear DRL (Daytime Running Lights): G20 Coding
How to code rear DRL on BMW G20 to illuminate together with front DRL using obdthink? Step-by-step module paths and warnings.
— Tekin Code
Enabling BMW Rear DRL (Daytime Running Lights) (G20)
Want the rear LEDs to illuminate when the front daytime running lights (DRL) are on during the day? On the BMW G20, this provides both a more distinctive appearance and increased visibility. Let's enable rear DRL step-by-step with obdthink.
What Does This Feature Do?
The rear brake/park LEDs illuminate at low intensity in sync with the front daytime running lights. This makes the vehicle appear "active" from the rear as well.
Requirements
• obdthink app
• OBD adapter or ENET cable
• BMW G20 / G21
Step-by-Step Coding
1. Head Unit (HU_MGU)
- Activate the DAYDRIVING_LIGHT_REAR parameter under HMI_SPEECH.
- Code.
2. BDC (Body Control) – Expert Mode
- Activate the Feature_4 parameter under 3702 LicFeatures.
- Code.
Verification
Turn the ignition off and back on, then check the rear of the vehicle while the daytime running lights are active; you will see the rear LEDs illuminated.
Common Issues
- Rear LEDs not illuminating: One of the two modules may not have been coded. Apply both HU_MGU and BDC steps.
- Conflict / error after software update: Some users report having to revert this coding after an update. If you experience issues, restore your backup.
Warnings
In some countries, continuously illuminated rear lighting may violate traffic regulations; check your local rules. All procedures are at your own risk.
Conclusion
Rear DRL is a visually distinctive coding that takes just a few minutes. With obdthink, you can complete the procedure in two modules and make it permanent.
Frequently Asked Questions
Does rear DRL shorten LED lifespan?
Since the LEDs operate at low intensity, the impact is negligible.
Is it legal?
It varies by country; check your local traffic regulations.