So if this sounds like AI helped me generate it, it did. But I did not want to post something weak that left too many questions to be answered, I'm not being lazy, I just really want to bring this thing to life because the electrical issue is the only thing I need to solve before I get it inspected and back on the road:




I'm dealing with a headlight control issue on a 2016 MINI Cooper S (F56, manual transmission, U.S. model, halogen headlights, non-adaptive) and am hoping to get targeted input before replacing the BDC (Body Domain Controller).
Symptoms:
Low beams remain on even with ignition off, key not in vehicle, and headlight switch in the OFF position.
High beams do not activate at all, even when engine is running and I pull back on the 'stalk'
All other lighting and comfort systems (blinkers, running lights, brake lights, windows, sunroof) are functioning normally.
What I’ve Done:
Battery disconnected for diagnostic safety.
Glovebox removed to gain access to fuse panel and expose the BDC module behind the passenger-side dash.
All visible fuses behind the glovebox checked
No visual signs of corrosion, burn marks, or water intrusion around the BDC.
With lamps plugged in and ignition off, pulling F44/F47 (low beam fuses) immediately shuts off the headlights. Reinserting causes lights to turn back on even without ignition or switch input.
High beams never respond, even with car running and stalk manipulated.
Background:
Vehicle suffered cosmetic damage to the front and rear passenger sides earlier this year. No airbag deployment, no intrusion into the dash, and no known electrical system involvement.
Interior is dry, BDC area clean. No evidence of flooding, dampness, or connector issues.
What I’m Thinking:
I suspect a logic-level fault or software issue in the BDC (where it’s erroneously commanding the low beams on and ignoring high beam inputs). That said:
The fact that pulling fuses disables the lights suggests the BDC isn’t "welded on" — it’s still obeying fuse logic.
It could also be a faulty signal input, like the stalk or headlight switch misbehaving.
What I’m Looking For:
Has anyone experienced these specific symptoms (low beams stuck on, high beams dead, everything else functional)?
Any way to test the BDC outputs or inputs directly (e.g., pinouts or voltage check)?
Can a faulty stalk or switch assembly send “always-on” signals for low beams or suppress high beams in this model?
Any relearn, reset, or programming sequence that can rule out software errors before I try a replacement BDC?
If I do test with a used BDC (~$200), and the exact same behavior persists, I am assuming it is not the BDC... and Ill be back at the drawing board.
Thanks in advance for any experience or technical insight you can share. I’ve done my best to rule out basic fuse or wiring issues and would prefer not to throw parts at this unless I can isolate the fault more confidently.