Automatic Brightness & Ambient Light Sensor Not Working!

[pamfu]

I am having this Xperia Mini Pro in my family since May 2012. When I purchased, it came with GB, and very soon there after, the update/upgrade to ICS was released. The upgrade was duly installed through the PC Companion.

I had initially noticed that there is no "Automatic" option under Menu → Settings → Display → Brightness. But then, the handset was in use mainly by my wife and I didn't think much about it since she always keeps the brightness at maximum or near there. Recently we swapped handsets and since I'm a heavy user, I looked for the setting to reduce battery usage, but couldn't find it!

I thought there must be some miss/bug in the software. I downloaded "Andro Sensor" from the market and there is no "Ambient Light Sensor" shown by that app! In fact, it says Light sensor not supported - see screen shot below:

Where as in the "White Paper on SK17" found on Sony's website (http://www-support-downloads.sonymobile.com/sk17/whitepaper_EN_sk17_xperia_mini_pro.pdf), at page 5, it says "Yes" against "Ambient Light Sensor".

My question is whether the sensor is there in the production version or not? It is there, then it appears the sensor in my handset is not working and needs repair/replacement under warranty?

After the recent update to 4.1.B.0.587, I observe that my display brightness fluctuates randomly, and this happens very often. Why does that?

Any replies and guidance would be highly appreciated!

Thanks in advance!

[Aniketg]

the fluctuations of ur screen light shows that the ambient sensor is working,it happens because the angle of light affect the sensor either to decrease the brightnss or increase it...sometimes this logic becomes difficult for sensor and hence it fluctuates...when it happens try to cover the sensor by your finger,those fluctuations will stop.

and its the major clue that ur light sensor is working.

if you want to check it take ur fone in dark and fire light on the sensor...the sensor brightness will increase,try this for 10-12 sec then turn off that light,now the screen brightness will decrease..if these things happens your sensor is all right.

[pamfu]

Aniketg, thanks for the reply! I'll try what you've suggested and then reply again. In the meantime, I wish to mention here that I had tried the reverse of what you've suggested - kept the phone in a well lit place and covered the top area of the front face of the phone where I expected the light sensor to be, but with no effect! That's why I got this doubt.

Any way, I hope to come back and reply by tomorrow!

Thanks again Aniketg

[pamfu · Accepted solution]

OK! I tried the following:

Dialled *#*#7378423#*#*

Selected "Service Tests"

Selected "Ambient Light Sensor"

Covered and uncovered the top portion of the front face of the phone to observe changing values for the sensor!

The results I got proved that the sensor is present and fully working! But still, no "Automatic" option in Display Brightness settings - is this a problem with Sony's implementation of ICS? My phone is updated to 4.1.B.0.587.

Thanks any way!