I have a 99 f250 and couple months ago it seemed like the batteries died. Then eventually everything died, there was no power at all. I have charged the batteries and had the alternator looked at but I still have no power. No lights or nothin. Don't know what to do. I also cleaned up the terminals but no change.

 

Welcome to the FTE

How old are the batteries? It's possible for a battery to measure OK, but choke under load. Not saying that is what is happening here, but it's something to be aware of. Batteries have to not only charge up, but be able to hold a charge.

When you measure the voltage across the positive and negative terminals and turn on headlights what happens to the voltage?

 

Have you tried another batt?
Follow the cable from the driver side leading to the fuse box, make sure its not corroded and make sure you got current going into the fuse box

 

Yea bad batteries. I guess the broken alternator ground killed the batteries. She's alive again. Thanks for the input.

 

Good to know everything worked out