Limp mode
 

I have a 2009 gmc 6.6 duramax with edge attitude with juice. It had the cts on it first about a month ago I switched tunes to 7 and it immediately thru check engine light on but ran fine. A mouth after I switched tunes it thru itself into limp mode and it's say egt high voltage and low voltage I've tried everything scanners dealerships nothing seems to help. It does not have the practical filter on it and I wanna say it doesn't have a egr cooler either.