I have a 2007 f350 6.0l 4wd crew cab single rear wheel and the Brake light on the dash as well as the 4 wheel hi and low light come on at random times and will stay on for sometimes an hour at a time along with an awful buzzer sound. I took it to the dealer they said it was a gem module problem they replaced $500 later still have the same problem. now they are saying they are not sure possible instrument cluster problem. I asked for a guarantee that it would fix it before I spend 1000 but they aren't sure. Does anyone have any ideas. I do have autoenginuity if there is something I can check. Thanks Michael

I get codes C1446, B1892, P1832,P1876, P1804, U1900