4500 Gmc Duramax

Any help on this issue would be greatly appreciated! I think the truck is possessed!! Just kidding, well maybe not. Lots of trouble with the electrical system. Just changed sensor that shuts off truck when coolant low and fixed shorted wire. Now, after heading down the road thinking all is well, no power, blinking dash board lights and gages. At my wits end on this!! It is a gmc 4500 topkick 2007. Any ideas???

4500 Gmc Duramax