Iam having the same issue with my astro awd. Sevice awd light on. Codes say its the encoder motor, well, I have been told there is a flow chart to id the problem, There s a possible wire to the encodor motor broke or the control module for the tranfer case is bad. My front dif does not work with this problem. It would not bother me to put the money into the van, with 206,000 miles. Beings its 1 of the best things GM has made, but, in there infinite wisdom they decide to stop production? Why kill what works. Maybe thats why they need the bail out.