What is a battery saver relay.

Here's a diagram of your charging system. I'm not sure of what info you need. There is no Battery Saver Relay - at least not one that is serviceable - there are add-on's for police packages.

Thanks for diagram. I have new altenator , new battery . New altenator plug. New cable to fuse box from altenator. Still getting 12 v from altenator , I need 14 v to charge batt. Can't figure it out, mabey faulty ignition. Don't know. Need help. Thanks

You have a floating ground, which means you are loosing the 2.1 volts you are looking for. Do several to many voltage drop tests starting with your voltmeter black probe and sticking it into the battery negative post and your red meter probe to the post cable clamp. Write down all your values all the way back to the battery positive post. The bigger difference of voltage difference are where you have higher resistance, or a low resistance to ground. Do not clean, or tighten anything until you perform all voltage drop tests because you will see this concern again in the future, and by isolating and identifying the culprit, you can get to it much faster next time than to re-inventing the wheel. You can also help others, and they will thing you are a Guru, almost mystical. Maybe you can start a new religion! Just don't go around blowing things up, but helping spread the knowledge. Invest in a good set of wrenches, torque wrench, dielectric grease, and a wire brush. Lastly, get yourself a wiring diagram of your vehicle and start learning to read it like as if your life depended on it. Keep in mind that charge particles come out of one the the battery posts, go through the wires and circuits, and return to the other battery post. Voltage is consumed across resistive loads as power, and energy is stored in capacitive and inductive loads. Use Ohms law to calculate the resistive load consuming the 2.1 volts. There is no easy answer, but the answer is not the fun part, but the journey.