Smart Auto Locksmith
Central Scotland

Smart Key Services — Mercedes IMMO for Original Fortwo and Forfour, New EV Models Explained

Smart has undergone two distinct phases that directly affect key service availability. The original Smart — Fortwo MK1 (W450, 1998–2007), Fortwo MK2 (W451, 2007–2014), Fortwo MK3 (W453, 2014–2022) and Forfour MK2 (W453, 2014–2022) — used Mercedes-Benz Group IMMO architecture. Mercedes Group OBD equipment covers all original Fortwo and Forfour generations for all key services with no year limits. This is a critical point: unlike the BMW post-2019 AKL restriction that affects BMW passenger cars, Smart carries no equivalent restriction. A 2021 Smart Fortwo MK3 is as accessible for AKL as a 2005 Fortwo MK1. Thatcham Research rates Smart vehicle security as part of their Mercedes Group assessments.

The new Smart — Smart #1 (2022 onwards) and Smart #3 (2023 onwards) — are produced by a Geely/Mercedes joint venture and use a Geely-derived EV platform that is entirely different from the Mercedes IMMO architecture covered by Mercedes Group equipment. For Smart #1 and #3 owners, please call before booking — I will confirm whether the job is within scope and what process applies before I travel. I will tell you honestly on the call rather than attend and find a different architecture. The two phases of Smart are genuinely distinct vehicles from a key programming perspective.

For the original Fortwo and Forfour, the key system evolves across generations. The MK1 Fortwo (W450) used a standard blade key system. The MK2 Fortwo (W451) introduced a more conventional Mercedes-style fob. The MK3 (W453) and Forfour MK2 (W453) use a push-start smart key on higher specifications and a standard fob on lower trims. The W453 Forfour was developed alongside the Renault Twingo MK3 on a shared platform — however, the key IMMO system on the Forfour uses Mercedes architecture rather than Renault’s Zedfull-covered system. Call with your specific Smart model and year to confirm the key type before booking.