Early 2000s S-Class and E-Class models (limited to non-CAN modules). Accessible Control Modules
The Carsoft L-Link is essential if you own a W124, W140, or R129 with the 38-pin connector. For W210 facelift or newer, buy a modern tool.
Understanding the nomenclature of the explains exactly how it communicates with an older vehicle's Electronic Control Units (ECUs):