Transfer case stuck in 4hi or auto 4wd

[Oshkosh]

Hi,
2000 gmc yukon xl 1500 4wd, newer push button switch, service 4wd light on, 4wd hi light on and in 4wd.
Push 2wd and light blinks, I hear front axle shift in and out, the transfer case encoder motor turns on but doesnt turn when shifting threw buttons??? I have unmounted it and watched...Any ideas?

 

[alacran]

following...
this happened to a friends tahoe

 

[Oshkosh]

I replaced the transfer case encoder motor with a cardone unit, after my second one(1st was defective) transfer case seems to be back in 2wd.
That being said I haven't driven more than 100yds yet.
The service 4wd light is still on...Not sure if I have something else going on yet or not.....
I am planning on changing the autotrac fluid this week..
If the light stays on will have to have codes read....

 

[Oshkosh]

Well service 4wd light still on, not shifting consistently ,leaning towards bad tccm....
That being said are there any sub $300 code scanners that will read gm tccm codes?
I'm looking at a craftsman 939853 but it is unclear if it will read the tccm???

 

[SLCHOE]

Disconnect the battery cables and touch them together for s few seconds. Codes will be stored in memory until they are either cleared or you do a battery disconnect.

 

[Oshkosh]

I tried disconnecting the battery then pulling atc fuse etc etc....
There is no #13 on the data plug to ground as some gm's have,a scanner is the only option to retrieve codes on this model..

 

[ATIII]

I tried disconnecting the battery then pulling atc fuse etc etc....
There is no #13 on the data plug to ground as some gm's have,a scanner is the only option to retrieve codes on this model..

Check around at your local parts stores. Advanced and O'reilly are really cool here and will read and clear codes, you just have to push the confirm button on their scanner to clear them. They technically aren't allowed to do it.

 

[Oshkosh]

From what I've been able to find online (which isn't much)
I need a code reader with "GM Enhanced " software, a good obd2 unit will Not read tccm codes.....
Which means my decent $150 code reader is useless in this matter....
I refuse to give local dealership $100 for 10 minutes work,thus I will locate and upgrade to a gm enhanced unit...
I an just trying to see if anyone has purchased a reasonably priced unit.
It looks like I can make it work threw scantool for under $200-....