The error codes are for the high and low range actuators there is a solenoid in the back of the trans on the pass side it is a little smaller then a pack of smokes either a plug to it and four bolts that might be the culprit unless you have an issue with te wiring harness or the speed sensors with the automatic trans it's hard to figure it out I would say take it to a shop there is a lot of possibilities prob electrical maybe even mechanical