My problems started with a loose battery + connection. The symptoms were the truck was stuck in 2nd gear and no power to tach or speedometer. I quickly went back home and tightened the connection. That fixed those problems. I thought that was the end of it until a couple days later when I drove the truck. Now I have no power to the HVAC controls and the ABS light is on. I have verified all the fuses have continuity, but I don’t have 12 volts to fuse slot 12. It is a 25 amp marked HTR/AC. It is located in the cab on the driver side. Does anyone know if the power to it is controlled through the ECM? Does anyone have any trouble shooting ideas? I am an electrician by trade so I’m more than willing to dig into some wiring but not sure where to start. Any help is greatly appreciated.