Proximity sensor doesn't work properly except for 9.9.3 firmware


dmvoron

Members
Sep 28, 2020
5
3
Hello. I came across the fact that the proximity sensor stopped working correctly on my phone for several months. I have already read many forums on this topic, and I know that the problem is often not solvable. But I noticed that in firmware 9.9.3 the sensor works perfectly during a phone call. At the same time, on any other more recent firmware, the sensor does not work correctly during a call.
I have flashed the phone several times for different versions of weekly firmware, but each time the sensor works correctly only on 9.9.3 firmware. Perhaps this is a hardware problem, but if the sensor always works normally on 9.9.3 firmware, then I ask for help in understanding the reason why this is happening. Is it possible to identify and transfer the settings related to the proximity sensor from firmware 9.9.3 to a more recent firmware?
 

dmvoron

Members
Sep 28, 2020
5
3
Are there any developers on this forum who know the nuances of the firmware and can understand the problem?
 

sfxsfx

Members
Oct 15, 2020
6
3
Just a random comment that maybe helps you. Have you try calibrating the proximity sensor? Sure you tried because you look quite experienced, but maybe...
 

dmvoron

Members
Sep 28, 2020
5
3
Just a random comment that maybe helps you. Have you try calibrating the proximity sensor? Sure you tried because you look quite experienced, but maybe...
Thanks for your reply. Yes, of course I tried, but it gave nothing. Well, the sensor calibration is missing in the latest versions of the miui.
 

sfxsfx

Members
Oct 15, 2020
6
3
Thanks for your reply. Yes, of course I tried, but it gave nothing. Well, the sensor calibration is missing in the latest versions of the miui.
Have you tried using this code in the phone calls?
*#*#64663#*#*

apparently in some Xiaomi model it unlocks more calibration options

source
 

dmvoron

Members
Sep 28, 2020
5
3
Have you tried using this code in the phone calls?
*#*#64663#*#*

apparently in some Xiaomi model it unlocks more calibration options

source
No, I haven't tried it. This combination really unlocks the proximity sensor calibration on Miui 12, thanks! But in my case, calibration again did not help. The sensor passes the test only after 10-20 attempts or does not pass at all, and does not work correctly during a call. At the same time, with firmware 9.9.3, the sensor also fails this test, but it always works correctly during a call. Why does the proximity sensor work correctly only on firmware 9.9.3 or earlier? Please help me understand...
 

sfxsfx

Members
Oct 15, 2020
6
3
Its a weird situation yours. I work in tech, and my feeling is that Xiaomi place in the market lot of stuff that it is not completely tested. Lots of products are super buggy. They sell themselves as a company with good hardware and affordable price, if this is the case, clearly they have an awful UAT process and they try to place lots of products in the market (hardware and software) without the appropriate testing.

In my case I think is a hardware damage. I tried a lot of things and I wasn't able to fix it. I am asking for a return of the money, I don't want another buggy Readmi Note 9. I bought a phone, not a problem.
To be honest, after this experience and digging into forums, Xiaomi hasn't a very good reputation, and it is just hyped.

I would like to be more useful and optimistic, but I think that the best solution ,if you can, is to ask for a replacement or the money back. I suspect that there is not much that we can do. Also, Not only Redmi Note 9 has this problems, lots of phones have this problem, so clearly is a know issue since a while (hardware and software) and they just give a f**k.