Here's how to check the switch for proper operation:
With connector plugged in, backprobe each wire, and press buttons and take voltage readings in w/ ground as reference. Key on for all tests. Also, turn the main cruise switch on for readings, too.
Brown: 12v
Black: 0v (when you press the on button, if the little light lights up this wire's fine)
Dark Blue: 0v, Press S/C button: 12v
Grey/Black: 0v, Press R/A button: 12v
Grey: 12v w/ cruise on, 0v w/ cruise off
Light Green: 0v, Press Cancel button: 12v
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