I had an extra master door switch lying around and thought I would open it up to see if I could take the illuminated switch that is labeled AUTO and use it to replace the non illuminated switch that is labeled AUTO. That way both of the AUTO switches would be illuminated. In case anyone else has thought of doing this it does not work. The little LED that supplies the light is not attached to the switch itself but to the circuit board for the entire assembly. And I was all happy because I thought I found a quick little fun mod

 

You can still do it... You just have to get creative.

 

If I recall correctly, the "auto" switch on the driver's side that controls the driver's window is illuminated but the auto switch (on the driver's side) that controls the passenger window is not illuminated. I am guessing this is the one you are trying to replace since the passenger side on mine is illuminated. If that is the case, replace the switch with the LED'd one and you should find two pins in the harness that are unused. Probe the other switch and find the wire that has voltage only when the lights are on and bring that power to the harness.