Heater blows cold air, there's no anitfreeze leaking into truck. Just wanted to check the fuses to see if there is a related fuse that might need replacing. Can't think of anything else short of taking it in to a mechanic. Pulled off fusebox cover but don't have an owner's manual that shows the configuration. Does anyone know if there is a fuse for the heating system and where it's located and the fuse rating? Thanks! Steve