service 4wd

[Zack Denson]

got in my truck 2006 silverado 2500HD duramax this morning and "service 4WD" came up on the cluster (notification center?) i checked the switch and im pretty sure its fine when i try to go in to 4wd high nothing happens the light just blinks if i try to go to low the transmission swaps into the lower gear but stays in 2wd with the light blinking i regularly exercise the 4wd anyone have any idea what it could be not looking for a definate just possibilities

[kstruckcountry]

Get it scanned first, good chance it's the encoder motor sensor though.