Laptop screen wont brighten when unplugged. help.?

I have a Dell Inspiron 1420. It is one and a half years old so it really isn't that old. But lately I haven't been able to brighten my laptop screen. It is getting frustrating because when i use my laptop while running on the battery I strain my eyes because I can't see the screen.





I have done the whole press Fn and brighten the screen. I've tried and changed the settings. Everything in each power saver to balanced setting is 100% set brightness (plugged and unplugged) but the only time my laptop would brighten is if it is plugged in.





I have a good amount of computer experience so if anyone knows how solve this please help!Laptop screen wont brighten when unplugged. help.?
Firstly you can go to your graphics option and check there. Or go to the Dell Quick Set options and change brightness there.



Also when rebooting, when you are at the Dell logo tap F2 to go into the Bios and there is actually a setting in there, well there is for my Vostro 1500



Good luck!Laptop screen wont brighten when unplugged. help.?
Well, if your laptop is running on the battery and running like normal on it then the battery would not cause this issue. I think it is a issue with your inverter board for the lcd panel. Only way to know for sure is to have someone test it or replace it and see if it works. I know the screen brighten when power adapter is inserted but, the inverter still could be bad. Good luck.Laptop screen wont brighten when unplugged. help.?
Sounds like your battery is starting to wear out. Consider buying a new one.

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