Nope. You just need a new battery. Once you managed to get the engine started with just jumper cables, which is quite an accomplishment in itself, the alternator keeps the electrical system going. It is supposed to recharge the battery too, but not when the battery is bad. The engine and the rest of the electrical system will run on the alternator until you stop the engine, then everything will be dead again.
Also be aware that the battery helps to stabilize the electrical system from voltage spikes and surges, and you don't have that protection right now. What you basically have is you're running the engine with, in effect, no battery. That is real bad news, and I have about a two-hour reply that I copy and paste when I read that someone did that. If this was a GM product, they have a real miserable generator design, (Chrysler developed the "alternator" and copyrighted the term), that develops huge voltage spikes under the best of circumstances, and disconnecting the battery with the engine running can destroy multiple computers. Chrysler systems are much more forgiving, but it's still not good practice to run the engine with no battery or a failed one.
There's one more thing to be aware of. Alternators and generators are real inefficient at low speeds. That can save you from doing damage to other circuits and computers. Do not raise engine speed or try to drive the car like this. As the alternator speeds up, its output voltage will go up a little, and that voltage is also what makes it generate its output voltage and current. The faster it goes, the higher the voltage goes. It is real easy to reach over 30 volts, and that's what destroys computers and any light bulbs that are turned on. The voltage regulator is supposed to control that, but the battery is the other part of the team. The voltage regulator can't control system voltage by itself.
Thursday, June 25th, 2015 AT 12:51 AM