How to synchronize the 4WD

get a code U1026 and I think U1049 (lost notes) communication loss can I trick the switch somehow unconnected

No tricks to the computer controlled circuits. The module communication circuits needs to be found and repaired. Could be between the case module and encoder, I have seen broken wires between them before in the harness from debris of 4 wheeling. The best and ideal way is to use a Tech2 scan tool and test the system and determine where to start.

what if key was on when I changed buttons

It could have spiked the control module.