More than likely the clicking that you are hearing is the encoder trying to engage but it cannot.
So, the likely cause of this is the encoder has failed but we need to do some testing to confirm this.
Let's go to the encoder on the side of the transfer case and check the voltage on the motor wires and see what it is when you are operating the switch.
I am attaching the wiring diagrams below that will help with this.
Please let me know what questions you have, and we can go from there.
Images (Click to enlarge)
Wednesday, January 12th, 2022 AT 5:17 PM