P0800 Code Transfercase 2003 Yukon

[Saucy_Walnuts]

My 2003 GMC Yukon has developed a P0800 Code but all connections are good, it shifts through 4Lo, 4Hi, and 2wd fine. It has a newer Encoder from when I swapped transfercases about a month ago. What could possibly be the issue? Should I not be super concerned because everything works fine on the transfercase even "Auto 4WD". I'm fairly new to GMT800s.

 

[Joseph Garcia]

@NickTransmissions is our resident transmission expert, and he will chime in with his thoughts.

 

[Saucy_Walnuts]

Transmission shifts fine, so maybe not TCM related? But I can't be certain, I'm still learning these trucks.