Need help trying to figure out what happened
My husband tried to install a bully dog in his 2007
GMC Sierra after he installed it the truck won't
crank. He took the bully dog out but it still won't
Put the bully dog back in and put it back to stock settings and see what happens. If nothing still works then it blew out all the factory programming and the vehicles systems will have to be reflashed by a GM dealer.