Cheap Mercedes-Benz E-Class Body Control Module

The Body Control Module (BCM) — sometimes called the SAM unit (Signal Acquisition and Actuation Module) on Mercedes-Benz vehicles — is a genuine E-Class component that controls functions such as lighting, wipers, central locking, and auxiliary systems. Used units can work, but Mercedes SAM modules are typically coded to the vehicle and will almost always require programming or coding to your specific car after fitting. Make sure you tell the breaker your exact registration so they can match the correct unit, and confirm with them whether the unit they're supplying has been cleared or will need coding by a specialist.

These two cars fall in the same W212 generation (2009–2016, facelifted in 2013), but the facelift brought changes to several electronic systems including the SAM unit, so a pre-facelift (2009–2013) unit and a post-facelift (2013–2016) unit may not be directly interchangeable. You should confirm with the breaker against your exact registration and the donor vehicle's registration before purchasing. Even within the same facelift phase, correct coding to your car will almost certainly be required.

On the W212 E-Class, there can be variant-specific differences in SAM unit configuration depending on the engine and transmission fitted, because the module communicates with drivetrain systems. This means you cannot simply assume any W212 SAM unit is interchangeable regardless of engine — confirm with the breaker that the donor vehicle's engine and gearbox match yours as closely as possible. Always quote your registration to the breaker to help them identify the correct unit.

Unlike some parts where trim level makes no difference, the SAM unit on the E-Class can vary according to which optional equipment and features were fitted to the original car, and AMG Line or Sport models may have had different active systems compared to an SE. Because of this, trim level is worth mentioning to the breaker, but the most reliable approach is to match donor and recipient vehicles by registration rather than trim name alone. Confirm the donor spec with the breaker against your registration before buying.

The W211 (2002–2009) and W212 (2009–2016) are entirely different generations with different electrical architectures, so their SAM units are not interchangeable. You need a unit sourced from the same generation as your car, and ideally from a vehicle with a matching specification and build date. Always give the breaker your full registration to make sure the donor vehicle is the right match.

When contacting a breaker through Findapart, give them your full registration number, as this allows them to confirm the exact part number and whether the donor vehicle's spec is compatible with yours. It is also worth asking whether the unit has been cleared of its previous coding, and whether you will need a Mercedes specialist or dealer to recode it to your vehicle after fitting — this is almost always required and is an additional cost to factor in. A reputable breaker should be able to advise on the donor car's engine, trim, and build date to give you the best possible chance of a successful fitment.