Used Mercedes-Benz B-Class Door Lock Mechanism

These are from different generations — the first-generation B-Class (W245) ran from 2005 to 2011, while the second-generation (W246) ran from 2011 to 2018, so a 2009 mechanism and a 2013 mechanism are from entirely different platforms and will not interchange. Always buy within the same generation to have any chance of fitment. Confirm the exact part against your registration with the breaker before purchasing.

Both years fall within the second-generation W246 B-Class (2011–2018), which received a facelift in 2014, so you are potentially crossing a facelift boundary here. The door lock mechanism may or may not have changed at that point, so while the generation is the same, you should confirm with the breaker whether the pre-facelift and post-facelift parts are interchangeable for your specific door position.

Trim level does not affect door lock mechanism fitment on the B-Class — the mechanism is determined by the generation and which door position you need (NS front, OS front, NS rear, OS rear), not by whether the car is Sport, SE, or any other trim. You may find trim-related cosmetic differences on surrounding parts, but the lock mechanism itself is the same across trim lines within a generation. Just make sure you specify the correct side and door position when contacting a breaker.

Yes, it matters significantly — door lock mechanisms are side-specific and cannot be swapped between the driver's side and passenger's side. In UK terms, the driver's side is the OS (offside, right-hand side) and the passenger's side is the NS (nearside, left-hand side). Always confirm the correct side with the breaker and check it against your registration to avoid ordering the wrong part.

No — engine size has no bearing on door lock mechanism fitment whatsoever. What matters is the generation of your B-Class (W245 2005–2011 or W246 2011–2018), the door position, and the side (NS or OS). Tell the breaker your registration and the door position you need, and they will be able to identify the correct part regardless of what engine is under the bonnet.

The W245 B-Class ran from 2005 to 2011, and parts from within that generation are your best starting point for fitment compatibility, though you should always confirm the specific year and door position with the breaker as there may have been running production changes. Used parts for the W245 are increasingly harder to source as the cars age, so it is worth contacting multiple dismantlers through Findapart to compare availability. Never assume fitment without checking your registration details against the donor vehicle.