I did some searching and found some info - but still don't quite know what is the issue.
The fan on my Jeep works in the three lowest positions, but not on high. In the three lowest positions, it blows out on high only, on high - it turns off. If you have the switch on high and give it a wiggle, it will come on sometimes.
I took out the resistor pack per the FMS and tested the resistance. The resistor pack appears to be working OK based on that.
I took out the fan speed switch from the dash. It does not appear to be burned or metled as some have reported. The FSM also said to check the resistance, I just was not sure where to test on that one.
So after my looking - I think it is the fan switch - but that is $100 compared to $20 for the resistor pack. Just want a second opinion before I go and spend money on the wrong thing.