The switch has 4 wires that go to it. 3 of them go to the cruise control module, the other 1 is a power feed wire from the ignition hot.
Colors of the wires are: Blue, Which is the 12 volt power supply from Ignition Hot. Green, Sends 12 volts to the cruise control Module when the switch is in the on position. (cruise Input control) Red, sends power to the cruise control module for the "set/coast" function. Yellow, sends power to the cruise control module for the "resume/accelerate" function.
Color coding is for the harness on the switch itself, Vehichle harness may be of different colors. Also note that the harness from the switch is encased like an extention cord, so to test them you would need to peel back the outer casing.
But like was already mentioned, check fueses FIRST anf formost.