The truck was sitting for 8 months. I needed to get a new battery and radiator. I replaced them and notice the drop in my battery gauge when using any accessory but notice a big drop when using lights.
My truck starts up fine with no problems. I have a new battery and the battery gauge says it is closed 14 volts. When I turn my parking lights on, the gauge drops 1-2 volts and i turn on headlights it drops even further. Checked alternator and battery already. Just seeing where a good starting...