witch cable is the hot one going to bttery

Hello, You will notice that one cable should be red, one black. The red is meant for positive + and the black is meant for negative - . If these have been installed backwards, the vehicle is likely in need of repair, as this will destroy a multitude of electronic components in the vehicle. It is called reverse polarity, and it is difficult to repair. The other thing, you might just have corrosion on the battery terminals, or the battery cables may have corrosion inside the sheathing. Testing may be required.