Proximity sensor fix confirmed

[Guest lambethboy]

I too have been battling with the problems with screen lock-ups when making calls and have just methodically worked through all the possible theories of causes and solutions to find a fix.

Android version

Seems like the most likely cause, espeically on a site dedicated to changing the stock version. But, with many people reporting similar issues on different phones and using manufacturer ROMs it seems less likely.

Crappy drivers

Quite likely I thought, may still be an issue in tandem with the dust issue. However, I was able to confirm a fix without changing any software.

Crappy proximity sensor chip (CM3602)

I work in the semiconductor industry and know how much effort goes into qualifying devices for manufacture, whilst this isn't impossible, it seems unlikely to me.

Cases & Protective films

I thought this was probably the likely cause, so I downloaded the Android Sensors app and tried cased/naked. It makes no difference, which rules this one out.

Dust in the works

As per this thread I thought I'd give it a try. Bingo the Android Sensors app now responds to my hand moving towards/away the speaker grill. Calls now work okay and I can even use the keypad to access my voicemail.

SOLUTION - vaccum your phone. It fixes it!

Cheers to moerph and puiloong for pointing me in the right direction.

PS I'm using 10.1-20130402-EXPERIMENTAL-u8815-R3 (not that this is relevant, it was the vacuum that fixed it!).

PPS Apologies if I'm stating the obvious, but it took me a while to find this fix.

[Guest fr0do]

Great post ;)

[Guest smweb]

How are you performing the vacuum?

[Guest kyan31]

This is an odd fix, but a very good find I guess :P

[Guest dakok]

Be careful with vacuum cleaner.

Tip of the plastic end part tends to collect static electricity.

[Guest george109]

Be careful with vacuum cleaner.

Tip of the plastic end part tends to collect static electricity.

I would suggest to use an air duster to stop that (a can of compressed air)

[Guest zeronickname]

I had much the same problems with my proximity sensor. Using some of the HW debug tools on the market I could see that it went from 9 to 0 when I moved a hand close to screen, but never reset itself -- in calls the screen never unblanked (I had to repeatedly tap the power button or squeeze the top right of the screen to get the sensor to respond)

I tried the compressed air technique and it didn't seem to help (if anything I just got dust between screen and glass).

In the end I took the phone apart and noticed that there was a fair bit of dust on the inside of the pane that covers the proximity sensor. Cleaned that off, put the phone back together and now the proximity sensor works again.