Climate control fan wont work on speed 3

2000 XJ - I'm guessing an actual control switch issue but when I turn my fan speed up to #3 it stops working, it does this with heat/vent or AC on. 1,2,4 speed positions work fine. Never hurts to ask right?

If only one position does not work, odds are that the switch is shot. If you pull the switch, you should be able to see.

Another way to verify if the switch is good is to probe the different positions on the switch with a voltmeter. IIRC, the way it is wired is that the switch will send voltage to each position, one at a time. While it is possible for the fan resistor to have a single tap not work, it is very rare.

Well it looks as if I have one of those very rare ones. I swapped out the switch and same thing. Is it possible to just change the resistor on the fan motor?

Update: Purchased a new resistor and presto 5 minute install and fixed.

too quick, was going to say if it's not the switch it's the resistor pack. Usually you lose 1, 2, and 3 but other failure modes are possible.