Ok so my lights on my 4x4 switch stopped working. At first it was just the lights indicating if I'm in 4h, 4low or 2wd. Now all those lights don't work at all. It still engages into 4x4. Could this be the wiring or the switch itself? It's bothering me that the lights don't work. It's a 99 jimmy sle.

 

Which dash switch do you have: three-button or four-button? The two different switches have different wiring systems. That's some important information when troubleshooting.

 

Sorry, it's the four button switch.

 

Two suggestions come to mind:
1) remove the 4x4 switch and look at the connector - is there any corroided contacts, contacts further into the plastic shell...etc. Spray contact cleaner on them.
2) take the switch to the workbench, separate the two housing halves to expose the circuit board and then re-flow every solder connection.

This worked on my 4 button switch when the 2HI lite would not stay on and tapping the switch a few times would make it light-up...but got tired of doing this every time I started the engine.