Battery light on dash?

[99' Powerstroke]

My battery light came on last night for the whole 1.5 hour drive home. The truck ran fine and I didn't notice the headlights dimming. I did lose the presets on my radio though. The truck started up strong as ever this morning but the light is still on. I checked the battery and alternator connections and everything was tight. Is this an indication that my alternator might be going bad or something else entirely? Don't want to buy a new one if I don't have to. Any help would be much appreciated.

[03_Turbo7.3]

yes sir, abtt light usually comes on if the Alt isnt charging or or batts are dead.. fast easy way to check the alt to even make sure it works is run the key on..dont start the truck..and take a wrench and touch the back of the alt or the front.. does it want to stick? yes..its atleast engaging..no? then somethings wrong.. there cheap to rebuild..could have a bad diode too.. if everything seems to be ok take it in and get an AVR test done..

[99' Powerstroke]

Thanks for the reply. I'll get it tested, and check into a rebuild.

[03_Turbo7.3]

Originally Posted by 99' Powerstroke

Thanks for the reply. I'll get it tested, and check into a rebuild.

Some places like autozone may even bench test your alt if you take it to them, i know ford regulators go bad too..easy to change

[ford diesel power]

stealing your post because i couldnt find another one. I noticed my battery light blinking eratically the other day. it only blinks when the lights are on but when i go up a hill or raise the RPM's it goes away. Then when i start coasting it starts again. The alt is a month old one battery is 3 months and the other is 2 years old. Any help please???

[X JBM X]

ugh. Bump up an old post.

Mine came on today, went off after about a minute of driving, then came back on, and stayed on.

Guess I'm going to have to test the alternator.

[paulgl26]

i had the same thing
180$ later (new alternator) the light is off
auto zone will test the alternator and charge the batteries for free
you should charge the batteries before you start the car with the new alternator

[Roc87]

Bought my F250 about 3 weeks ago, battery light came on middle of last week. Would go out at idle or just off idle, but as you accellerate the light would come back on. Found the receipt where previous owner bought new alternator at Oreillys back in January. Pulled off alternator, took it to 'em with receipt & they said it was bad, swapped it out, no more battery light