Transfer case issues

Hi Alex, thanks for your answer.

I think the AAMCO did the work like a year or more ago, the problem is the work was done in Sarasota and I'm in Miami.
I've visit some shops and they say the problem doesn't look like a differential problem, there is not any noise.
And yes just two or three times of many the Engine Light came up but just for a few minutes.
Can I still pull out any code DTC from the modules without the light?
Today I lost power in the front switches to close the doors. Can it be a fuse?
BR

The harness were removed from the main switch in the driver's door and everything working fine now after put them back
I have several questions.
1.- The 4x4 can activate itself and automatically?
2.- What if one of the wheels is hardest than normal?
3.- Why for is the speed sensor in the Tcase?
4.- And the decoder motor can be damaged?
Sorry but I'm trying to understand how the system works, before focus in the TCase replacement, is it true the car has to be reprogrammed if I change de TCase?
BR

When I place the truck in neutral and activate the switches, everything looks normal, lights change and everything, you can hear the transfer case changing and making the same sound
when the failure occurs the light 4WD unlocked remain lit.
Why do you suspect of the switch?
I've been reading a lot about transfer case and everything related lately,
the problem looks to me below, the 4WD engage without command and according to what I read, it can be caused for a defective VSS, or defective encoder, or definitely a bad TCase (folk) or other thing inside.
I also suspected the TCC module but I have inclination to think if the module is defective the lights should be changing, don't you think?
This is my plan.
1.- I will change the sensor,
2.- I will change the encoder if nothing happen
3.- I will have face the TCase replacement
one last question, any of these changes will require any programming?
I will keep you posted.

Sure, I have this complete manual.
Thanks

I have a risen question.
In case that I need to replace the encoder motor, what if it is in a different position than the T-Case?
Can I connect it to the harness and start on the truck without to hook it up to the T-Case?
BR

Two questions
Do I have to drain the TCase before the encoder replacement?

When I switch from 4WD to 4WDHi lock I can’t hear anything being in neutral and with the door open
Going back to 4WD I do can listen a little noise
When I go for and back to 4WD Lo lock I can listen a bigger noise

The 4x4 activates by itself if one of your rear wheels is getting hard to rotate than the other one?

I've not proceed because I was told after you replace the encoder motor or the transfer case you need to reprogram the modules. Is that true?

Okay, transfer case down, open and verified defective plastic fork (replaced).
My concern now is how to put back the piece that move the fork, any suggestion or it is easy?

Alex, thanks for your prompt answer.
Do you have all this in just one PDF?
Now I have several doubts.
I can see nothing related to the shaft I asked, the one that is moved by the encoder, and in the planetary I only have marks in two gears, is it okay?