I have a 2000 Silverado. I have no lights on my 4wd selector. on 2000 Chevrolet Silverado 1500

I put it in 4 low (trans in neutral). I heard the clank as it went into low. The low light blinked and then went out completly. Then the service 4wd light came on. It is low and I have no lights on my selector switch. The 4wd fuse is good. I have tried a different switch and 4wd module with no results.