Not sure about the newer trucks. The '08 truck has the up fitter switches notated in the owners manual along with the wire color codes and amp rating for each switch. The 4 wires protrude out of the harness by the E brake in the cab and they have heat shrink on their ends. There is also another set of 4 wires that are in the harness which go thru the fire wall in which you would connect to the wires from the up fitter switches at the E brake location to transfer power to an outside of cab function.