Battery drain

[nightkeeper62]

Yesterday I went to start my truck and it sounded like my batteries were almost dead and every gauge in the dash pegged out and then went back to normal. I popped the hood and noticed that a ground cable had some corrosion on it so I cleaned it. Started my truck and went to the mall. Once there I shut it off and then tried to start it. It started fine and sounded like the batteries had charged up a bit. After my appointment there I came out and it started just fine. I drove it for about an hour and then parked it. About 12 hours later I tried to start it and the batteries acted like they were dead. Just clicking. I let it sit there over night and this morning came home to put the charger on the batteries. It will turn over but very slow and my charger looks like it is saying the batteries are fine. What does it mean when all the needle gauges go full then cycle back?

Every time I turn the switch to the on position all gauges cycle full then come back. And I noticed a couple of days ago my nav comp on the roof was so dim I could barely see it in the day time.