i just bought a used 2014 730. I really don’t remember checking the bunk controls before I purchased it. Now I noticed that they are not working. I can turn the power on and the screen lights up but shows nothing. I checked all the fuses and they are good. Is that control panel something that goes out. It does have a idle free electric apu on it and the blower will come on for that and then it turns off. I usually can figure things out on my own but kind of new to big trucks. Any help would be much appreciated