I just got a 2000 Sonoma 4.3 4wd sls. I am having issues with my 4wd. There are no indicator lights for any of the 3 settings on the switch. We tested the wires that control the certain functions and they all read 14 volts when pressed. We also check vacuum lines everywhere and I changed the vacuum switch on the t-case and also the switch on the front axle. My truck is the model that does not have the extra vacuum switch on the firewall. So my question is why do I not have indicator lights and why does my 4wd not work. I'm lost.
