Or you could buy a test light. pop off your cover near the Ignition and test the wires to find out which one it is. How do I do that????? Well get the test light 1st. Put the key in and test all the wires. Then use the ones that don't turn on test light for the next step. NExt step turn the key to the ACC (when the radio comes on) and test the wires, Again ues the ones that don't turn on an out the key to the ON position and test. Phew that wasn't too hard was it.