all depends on your truck, ive been told that the 07 and up have a plug and play feature. how ever such the case like mine the 03-06 has to have a different harness. its called a clock spring harness, and has to come from a truck that had steering wheel controls! after the harnes is installed there are a series of computer flashes that have to take place in order for the computer to know its there. that usually is dealer thing unless your really good with computers! and have a tech two.