Body functions, access and the immobilizer live in the body domain controller (BDC). Its hardware changed during production: cars built from mid-2020 take a newer unit than earlier ones, so a replacement has to match the production date as well as the model.
Like every BDC, it holds the car's key and immobilizer data, so a replacement is programmed in or has the original's data transferred to it — a used unit off the shelf does nothing on its own.
From a documented source: transpondery.com CAS/FEM/BDC list.
Modules that fail on this one
- BDC (body domain controller)The FEM's successor — body functions, access, immobilizer and gateway in one domain module, from the 2014 X5 and BMW/Mini front-drive cars to the G-series.
Work this generation comes in for
- Diagnostics & Electrical TroubleshootingComplex, intermittent and non-standard faults in electronic systems and the digital data buses (CAN, LIN, FlexRay, MOST), and in the wiring itself: parasitic drains, water damage, chewed or brittle harnesses.
- ECU Programming & CodingProgramming, resetting, pairing and recoding control units of any complexity: powertrain, transmission, comfort modules, body electronics and multimedia.
- DME Unlock — BMW 2020+Bench unlock of the engine control unit on 2020 and newer BMWs — required before it can be read, cloned or reprogrammed outside BMW's own software. $399 per module.
- Control Unit Replacement & AdaptationFull-cycle adaptation and synchronization of both new and used control units, component protection removal, and configuration to the specific car.
- Airbag, Safety & ADASDiagnosis and repair of airbag, safety and driver-assistance systems — modules, sensors and the faults they leave behind after a hit.
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