turn machine off, turn on AWD, press override button for 5 to 10 seconds, continue to press override button and start your machine, after started release override button. Your instrument cluster is now in diagnostic mode. press and release the override button till you get to the AWD screen. if AWD says it is on, you have a mechanical Problem, if it says off, check the brown/white wire to ground, going to your hub coils, with the hub coils connected, if you have battery power, your AWD switch is bad, you have a wiring problem or your hub coils are bad. if your dont have power, pull your pod cover off, disconnect the 16 pin plug from the speedo, check for battery power to the brown/white wire, if you dont have power, its a wiring problem. remove throttle cover, disconnect wire connector, check continuity across your AWD switch, if you have continuity, replace speedo, if no continuity replace AWD Switch
I understand you say you just replaced the AWD switch, but it is know to get bad parts in new.
If this does not fix it, you have a mechanical prob