I am running an alternator and a gauge indicating volts and it barely shows 11 volts. I always drive with the headlights on and if I turn them off I will eventually show a positive charge on the gauge. I have manually checked the output of the alternator and the voltage at the battery with the engine running and they were well within specs. I could run a wire from the battery into the cabin while driving to double check the voltage while driving and noticing this low charge condition. Perhaps the gauge is off? I have a brand new battery in the car.