My 96 dodge ram 1500 slt 5.9 The positive battery cable was very corroded to the point were the wires were just hanging by a thread.

is there 12v supplied to the starter connection? for that cable. Is there 12v supplied to the start enable wire when you set all the controls and attempt to crank it ? If those are ok, then use a volt meter to measure the starter connection and battery during an attempt to crank it. if you drop voltage dramatically it indicates the cable has corrosion internally. If the voltage is still up to battery voltage or just below, that is the amount of volts being dropped. Connection to the battery must be cleaned to a shine with a wire brush, the same for the cable end and the starter connection. They must fit well and be tight. Your body, your frame, and your engine block must be grounded. Corroded grounds have resistances that cause voltage drop also. An example of a good connection at any point is less than 1/2 ohm. if everything seems right? tap the starter relay or solenoid. while attempting to crank. If there was no power at start enable wire, trace back to the neutral or clutch switch or the ignition switch

A battery that leaks can be responsible for this degredation. leaking and sweating at the battery creeps up the cables and corrodes them. A battery that swells and sweats while being charged can leak electrolyte and corrode everything in the battery box, the frame, your ground ? A battery that is low on electrolyte can have distilled water added. A battery that is weak in reserve capacity or passes a load test poorly or cannot pass can also be partly at fault. jumping and charging them must be carefully and watchfully done when they are suspect. baking soda is cheap. so is naval jelly and spray paint. my truck silently and patiently attests.