4x4 Indicator Light
Howdy. I have a 1990 Silverado. I've been messing with the 4x4 actuator quite a bit lately and began wondering what causes the 4x4 indicator light to turn on(it works fine, I just don't get it). With the actuator removed from the differential, you can move the 4x4 shifter back and forth between 2wd and 4wd and hear/see the actuator moving (I have the non-thermal one installed), but the 4x4 indicator light doesn't come on unless it's installed in the differential. I didn't see any wires coming from anywhere else to sense the engagement. Does anyone know what turns the 4x4 indicator light on? Thanks.