Windows 7: Keyboard brightness commands only work after 'Sleep', Latitude E5410

This has been going on for ages. Upon a fresh boot, keyboard brightness dimming does not work until I put laptop to sleep. Then, the FN+up/down works fine. I can't remember if this has always been the case, but I know when I first got my laptop, Windows 7 pre-installed, the auto-dimmer was working. Now I am not sure it is (not that I mind, I don't want it on). Now, when I check Advanced Power Options, the "enable auto dimmer" isn't even listed.

I pretty much need to have quick brightness keyboard control due to my light sensitivity. Win+X is annoying to resort to.

Also, when the FN+up/down keys DO work to change the brightness, it says:
"Ambient Light Sensor Disabled". If that helps for anything. (Also also, I checked, and I have no "sensors" installed, so says my system.)
Also, my keyboard has a FN+Auto Dimmer key that is the 'left' key in the arrow set, but it doesn't appear to do anything. Or am I completely missing that THIS might be what I need to hit in order to enable keyboard dimming commands? (I haven't tried, but right now, after coming out of Sleep mode, the dimming commands are working and the "auto" option does nothing).




Anyway....

Windows 7 Home Premuim
Dell Latitude E5410
Intel Core i5 m450 2.5ghz
4gb ram
32bit
DirectX 11
Intel HD Graphics 1562mb 60hz

Don't know what else you need to know.

I did some searching online and this might be a BIOS setting, but I didn't want to go that route before I talk to someone.

(PS, Power Options, as far as I can tell, only lets me manually, on the screen, adjust brightness - it seems to have no control over keyboard adjustment settings).

Thanks in advance.

Hi ally82,

My name is Sukanya and I work for the Social Media and Community Team at Dell.
I see from the issue description you have given it does not seems to be a hard ware fault ,but more to do with bios settings.What I would like to know is if you have reset the BIOS to default settings or have to updated teh bios recently.If you havent tried ether of the options ,I would request you to first Reset the BIOS to defaults and update Dell Control Point application if that do work flash the bios using teh below given link.
Drivers and Downloads | Dell [United Kingdom]
Please let us know if that is working out or not.

Regards,
Dell-Sukanya–M

Hello and thank you for replying.

I have not updated the BIOS ever, and the computer is about 2 years old. I support it can't hurt to call Dell (I'm still under warranty) to see if I need to update anything.

What I did just now was this:
Went into BIOS and looked at the screen settings
Reset to default, but all this appeared to do was change the bar-scale on how bright battery/AC will be.
After resetting to default, I moved the slide scale back to where I would want it, then exited.

There was no option that I could find where it set screen brightness to auto/manual.

However, I have done 2 fresh boots to Windows since going into BIOS and now the FN+up/down works fine. I could be imagining it, but I swear it even has a larger range of brightness/dimming.

Anyway, if this proves to not have solved whatever was wrong, I will do as you say. I have, in fact, observed that the dimming with FN+up/down working/not working appears to be completely random - sometimes it worked straight off, sometimes not til I put it to sleep....