Headlight and battery issues

dead battery,with the alt bolts loose the alt was not charging battery complety,after he tighten the alt the alt belt was tightened and over charged the battery killing a cell in it.

So, that could cause the headlights to go out while he was driving?

yes,once the battery isshot nothing will work,all it was running on was what power was in the battery,once the lights were turned on it pulled the rest of the power out,the alt could not charge it enough to keep it running.replace the battery it should be fine.I would have the alt checked ,it should be putting out 14 volts at idle with lights on.

If you had power and the headlights went out and still had power and running. Most likely not the battery . Headlight fuses are a breaker and if get hot enough Will trip but will normally come back on after a minute or two. Unless it went out . Not a common thing. Headlight switches get weak over time then tend to get hot tripping the fuse. Or sometimes a loose wire will get the switch hot and trip the fuse. Check connections to switch from back of panel if all Secure I'd change switch if keeps happening . There not that high and easy to replace bout 25.00 T.

Anther thing that could cause this problem is dimmer switch l.way to Check this is when light go out they normally go out on high beam change to low beam and see if stays on eventually will start going to when in low beam. Easy to fix just a little more pricey. 90.00 to 300.00 hope this helps good luck. T.

FORD F 350 2009 GAS EVERY BIT OF BATTERY IS DEAD INSIDE TRUCK WITH HOT BATTERY