Steering Wheel control Primary harness adapters convert the commands from your car's steering wheel controls to a code that an aftermarket radio can recognize. A patch lead is also requires for SWC type systems based on the brand of head unit you have. for more details check out our you tube video. http://aerpro.com/video/control_harness_installation CHMC5C C-CLASS 2006-2011(MY10)(W204)
This product is also known to work in the following vehicles: Mercedes C-Class 2007-2012 W204