T100 4WD problem

My 96 T100 extended cab 6cyl w/95k miles will not shift into 4WD. I can move the shift selector ok but the 4WD light does not come on and I don't think the 4WD is engaged. Does anyone know what the problem might be?

There is always the possibility that the indicator is burned out, though that would not prevent engaging the 4WD. Does your truck have Toyota's ADD (not attention deficit disorder)? Is it a stick or auto? The schematic diagram for the '94, which I assume is similar to yours, shows a fuse, a relay, a couple of switches, and the ADD actuator in the circuit.

Thanks for replying. I finally got it to work by repeatedly shifting back and forth. After several (30 or so) tries it went into 4wd and it has worked ever since. I think something was stuck because it had set idle for the about 6 months. :)