2005 Silverado 4x4 Problems

[MI_Silverado]

My dad has an 05 Silverado and it stopped going into 4 wheel drive about a month ago. The lights don't light up on the push buttons. He swapped out his push buttons with another truck and his worked on the other truck, but the ones from the other truck would not work on his. He had it hooked up to a computer the other day ( it was a Snap-On one), and it came up as " encoder motor invalid". He could light up all the push button lights with the computer.

 

Nothing come across the display on the truck to service anything. Anyone have any suggestions?

[gmtech4]

get it scanned by a REAL scanner called a tech2 and report the code

 

snap on scanners sucks