My 4x4 indicator is not working - won't shift from 2x to 4x. Also have a clicking noise under dash maybe near steering column. Sounds almost like a solenoid trying to engage / disengage. I have not fully checked fuses, just a cursory look-see. I also have the 4 whl service light on. Any help would be most appreciated.

With the "service 4wd" light on there are going to be some codes in the 4wd system module. Post back the codes. Also is your '99 an "old" or "new" body style? Do you have the "auto 4wd" system?

My 4x4 indicator is not working - won't shift from 2x to 4x. Also have a clicking noise under dash maybe near steering column. Sounds almost like a solenoid trying to engage / disengage. I have not fully checked fuses, just a cursory look-see. I also have the 4 whl service light on. Any help would be most appreciated.
this could be a bad dash transfer switch. my switch failed by taking a long time to engage and made relay clicking noises. and eventually threw a service 4wd lt. I read that in another forum years ago, that the switches were bad, and that the cost of the switch is much cheaper than dealer code read, so i removed switch found bad solder joints resoldered , now years later still running strong. only took 45min to fix. no tools needed to remove switch need small soldering iron and if you can solder wires, easy fix. if this isn't the problem then go to dealer could be very expensive repair....need dealer to scan i tried local non dealer repair shops they said scanner too expensive to buy.......

I work at an independant repair shop and we have 3 scanners capable of reading the codes. In the hands of a skilled technician, a $3,000 scan tool quickly pays for itself. That may say something about going to a shop that cannot read the codes.

The TCM (maybe TCCM) Transfer Case Control Module (located behind passenger kick panel) is a very common failure on these. Pull the big connector off and look for corrosion on the terminals. The terminals can usually be cleaned and will work for a while, but it's almost guaranteed to fail again. The module is around $350-$500.