Ambient Light Sensor cannot be disabled

[mendicim]

Hey,

I'm having an issue with an Elitebook 8530p.  The display brightness on the laptop is always fluctuating.  I disabled the Ambient Light Sensor with fn+f11 but that didn't work. it was still having an effect on the brightness.  So I disabled it in the BIOS and even though it's no longer be recognized by windows, its still automatically changing the brightness.  If i cover the sensor with my finger (simulating a dark area), it brightens up... but I would like to have this feature completely disabled.   Anybody have any ideas?

Notes:

- I updated the BIOS, display driver and HP quick launch button software to the latest versions.

- There is no entry in the device manager for the ambient light sensor (as far as i can see)

- There is no service associated to this in computer management.

Any help would be great!

thanks,

Mat-

[guilherme128]

I am having the same problem. did you have any luck contacting HP support? I disabled on the bios and still my screen eradically dims. It has a mind of its own.

[HaryKary]

I have that problem, too. My 8530p's screen auto adjust the brightness even i disable the ambient light. It make me difficult to use. Plz help.

[mendicim]

Hey,

I couldn't figure anything else out so I ended up having to contact HP.  It turned out that hardware was defective.  They replaced the unit since it was still under warranty.  Hopefully this helps...

[sihu89]

Think this information does not help those, whose warranty is out of date. Had the same problem over months and finally i found a solution...or a work-around. could be possible, that it is definitly a hardware defect.

my work-around was to disable the "Ambient light sensor" in the BIOS. Just restart the computer, than click ESC to enter the BIOS, and then select something like "built-in-devices", there you can find an option of the "Ambient light sensor", and you can disable or enable it. It's still better than the screen gets dark every time. Hope that helps some people too!

[Psy-Virus]

Hey there,

I know it's an old thread but there seems to be a fix for this.

For everyone who also have this problem of auto brightness regulation of your display even if you completely disabled the ambient light sensor and have an amd graphics card in your machine, try the following

"

1. Open the registry editor by pressing Win+R and typing in regedit
2. Browse to: HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4d36e968-e325-11ce-bfc1-08002be10318}\0000
3. Right-Click on the 0000 key (it looks like a folder).
4. Select New->Dword.
5. Name the new registry entry PP_VariBrightFeatureEnable
6. Double-click on the PP_VariBrightFeatureEnable entry you just created.
7. Make sure it has a value of 0
8. Click OK, close the registry editory, and restart the machine.

"

Sources:

http://h30434.www3.hp.com/t5/Notebook-Video-Display-and-Touch/How-do-I-disable-auto-brightness-of-th...

and

http://itmishmash.blogspot.de/2014/04/how-do-i-disable-auto-brightness-on.html

I did the registry "hack" and it works perfectly on my Elitebook 8460p.

So I hope every one who is googleling around and search for help, like me, will find this thread and will be cured from this ugly effect.

 Please HP-Support, this should be added to the FAQs, 'cause I searched since at least 2 Month for a solution and this thread here was one of the results that didn't bring up any solution... since now! 🙂

Greetings

Psy 🙂

[Rafat1993]

for this kind of display issue 

update the bios

update the video driver

update the chipset driver

thanks and regards 

rafat