Ac and heater not working after new battery install

[joel_mitchell77]

Hey guys, hoping someone can help me out, I just changed the battery in my fg xr6t, and since doing it I now have "system comms fault" coming up on the dash and my heater/ac aren't working at all. Like no buttons I press to control the ac do anything and nothing on the icc screen comes up for the ac. It's like it's totally disappeared. 

The stereo and Bluetooth etc all work but the heater and ac are gone completely. Checked fuses and all look good. Disconnected battery for an hour and re connected and still the same. 

Help.