1. Bigfireq's Avatar
    I have a problem with my 4S where I'm talking on the phone, but the screen remains on, and I can trigger buttons (such as Mute or Hangup) with my cheek. And guess what? I trigger them a lot!

    I had the same problem with my first phone, and exchanged it, and the second one has the exact same problem.

    Also, I don't have a screen protector, so I don't think anything could be interfering with the sensor.

    If it wasn't for this problem, the phone would be great. Does anyone have any suggestions for dealing with this problem? I can't believe I've hit this with two phones, but I can't find anyone else talking about it.
    05-16-2017 03:11 PM
  2. ttsoldier's Avatar
    There are problems with the proximity sensor.

    I have issues where even though the phone is by my ears, it changes to speaker. They really need a firmware update for this phone.
    05-16-2017 07:39 PM
  3. Bigfireq's Avatar
    Nice to know I'm not crazy, but strange people aren't up in arms about this.
    05-17-2017 01:01 AM
  4. xandros9's Avatar
    I would exchange it again if you could (I've seen bad cases involving more than a few replacements of a phone several years ago) but if the issue is truly as widespread as these three phones have suggested, the pool of affected devices is likely quite small.

    Now if it affected all Android-variants including the DTEK60, it might be higher-profile but seeing how it took a lot of reports for the LG bootlooping issue to take flight, I can't see this going much of anywhere other than hoping for a firmware update or low-level warranty repairs.
    05-17-2017 06:50 AM
  5. miraidave's Avatar
    As I have mentioned in the thread about the Creator's Update, I've exchanged my phone through T-Mobile warranty exchange twice, and all three phones have the proximity sensor issue. I do not think it is a hardware failure, but a firmware incompatibility with Windows 10 Mobile.

    I have identified that the proximity sensor will become non-responsive if you receive an incoming call when the sensor is covered, i.e. the phone is in your pocket or faced down on a table. If you receive a call when the sensor is unobstructed, it will work fine. Therefore, I believe this is a firmware/software issue and not a hardware issue.

    I uncertain if what is described above matches your exact issue, therefore I would try calling the phone in both the face up and face down positions to see how your phone responds. If the proximity sensor does not work in both scenarios, or if you are sending an outgoing call, you might actually have a bad sensor. If your phone responds exactly as I described then getting a new phone through warranty probably will not resolve the issue.
    editguy likes this.
    05-17-2017 09:13 AM
  6. nate0's Avatar
    I can attest to this (sensor issue), and have had this issue while the phone is locked and answering a call. If I hold the phone to my face when answered the backlight never shuts off hence the sensor is not enabled for some reason...Like posted just above, I am not certain if this only if the senor is covered or not activated or what.
    05-17-2017 12:29 PM
  7. nate0's Avatar
    Can we update the title to this thread, it has a spelling mistake.. @RumoredNow or another mod.

    This way if there are more folks seeing this they can easily find it.
    RumoredNow likes this.
    05-18-2017 07:41 AM
  8. editguy's Avatar
    I'm convinced that it's related to the Creator's update/firmware related. I've tried what miraidave commented on about the phone being pocketed/unpocketed and I got the same results that he did. If it's laying face up on my desk when I answer, no sensor problem whatsoever.
    05-18-2017 09:52 PM
  9. nate0's Avatar
    If bad or conflicting sw per the CU update then ask @fatclue_98

    He rolled back to the AU update. Maybe he would know if the T-Mobile model gets the same result.

    Also, I have had this issue since the updates on the last build, 14393.xxx before CU on the unlocked open market model.
    05-19-2017 02:37 AM
  10. fatclue_98's Avatar
    Mine was the T-Mobile variant but I never experienced the issue y'all have been discussing. That would've driven me insane if it happened to me. Quick show of hands, how many of you experiencing this have thrown your phones? We're family, speak freely.
    05-19-2017 05:23 PM
  11. editguy's Avatar
    Mine was the T-Mobile variant but I never experienced the issue y'all have been discussing. That would've driven me insane if it happened to me. Quick show of hands, how many of you experiencing this have thrown your phones? We're family, speak freely.
    I'm not throwing a glass-backed phone.
    fatclue_98 likes this.
    05-20-2017 12:56 AM
  12. nate0's Avatar
    05-20-2017 02:43 AM
  13. fatclue_98's Avatar
    Unfortunately, Google Services has stopped working.
    nate0, editguy, RumoredNow and 1 others like this.
    05-20-2017 11:18 AM
  14. RumoredNow's Avatar
    05-20-2017 03:18 PM
  15. nate0's Avatar
    Unfortunately, Google Services has stopped working.
    hahaha, that is because you are browsing a Windows forum...
    fatclue_98 likes this.
    05-20-2017 08:58 PM
  16. fatclue_98's Avatar
    hahaha, that is because you are browsing a Windows forum...
    Nah, even the most "flagship" Android drops that message every now and then and will drive you to pull a Nolan Ryan. I'm sure AC is littered with similar comments.
    nate0 and editguy like this.
    05-20-2017 10:01 PM
  17. nate0's Avatar
    Yes. The life of "first world" problems.
    editguy and fatclue_98 like this.
    05-20-2017 10:19 PM
  18. nate0's Avatar
    My freaking idol 4s keeps trying to call places and take photos in my pocket due to this issue. Every time I get a message or email it wakes up in my pocket now while locked. Frustrating.
    07-04-2017 11:03 PM
  19. gvp 1995's Avatar
    Good detective work, thank you 'miraldave'. A software bug confirmed. I bought 3 of these phones for each family member. Returned one because of this issue, thought it was a hardware problem. So, the good news is that it is not a hardware issue, the bad news is that it was first reported in this thread in May. Since then there were multiple updates, and it is not fixed yet. I will be very much surprised if it is fixed eventually. Looks like MS is dumping this specific model. Each phone has a specific build, from what I read, T-Mobile variant does not have this Proximity Sensor problem, meaning they need to fix specifically 4s unlocked.

    Interestingly, I read in another thread that double tap to wake could be related to this issue, and tried to find a work around. But in vain. It is related though. Such if you turn it On or Off, the very first time it behaves even if the sensor is covered, apparently because something gets initialized. But the second time it gets screwed again.
    12-26-2017 06:37 PM
  20. gvp 1995's Avatar
    A couple of new observations for those who have this problem.

    1. T-Mobile firmware gives the same result as unlocked
    2. Proximity sensor breaks at 1709 update
    3. For those who use T-Mobile everything is the same except added bonus WiFi calling
    4. There is no way to go back from T-Mobile firmware to unlocked.
    5. If you receive a call with opened Proximity Sensor, it works, as well as all outgoing calls you place late. However, if you receive a call with closed Proximity Sensor (in your pocket or in closed case), then not only it does not work for this call but for all outgoing calls afterwards. It is re-set by receiving a call with opened Proximity Sensor or by restarting the phone.

    It is a pity there is no work around this bug. MS is selling the phone for $99 and it would be a steal if not this bug.
    01-10-2018 10:05 PM
  21. greedo_greedy's Avatar
    The $99 deal from Microsoft is quite tempting indeed.

    Just have a question, I know this software issue is bothersome but is it really that bad that it will make me want to not use it? I mean it should still function and provide me with basic calls and texts right?

    Or is it really experience breaking that it will make me toss the phone at the pavement?
    01-11-2018 09:50 PM
  22. gvp 1995's Avatar
    After weeks of researching this issue, it looks I am finally approaching the understanding how this bug works, and more importantly - the solution.

    It is not binary works/does not work. There are 3 distinct modes of the Proximity Sensor on this phone.
    1. Sensitive
    2. Not sensitive
    3. Not working.
    I don't know how it is done on other phones, but here it looks they wanted to make PS respond depending on the proximity to the surface (maybe for double tap to wake?).

    The first mode engages when the phone is face up - no surface. When the call starts it is enough to bring the hand and the screen is off.

    The second mode (semi-sensitive) can be reproduced if the phone with no case put in the pocket or face down on the soft surface (furniture or something). Then brining the hand is not enough, but PS still turns off the screen if brought close to the ear.

    The third mode (non-working) can be reproduced if the phone with no case put face down on the hard surface - wooden desk in my case. Then, upon answering, there is no way the screen is off, no matter how close you bring the phone to your ear.

    In the process of these experiments, I collected 5 different cases. Some of them make it not working - for example, the one with the cover. To cut the long story short, there is one case CoverOn that serves both purposes: when the phone is face down on the hard surface, the case has enough ridge to trigger mode 2. At the same time the ridge is not big enough, so you can bring the phone close to your ear enough for PS to work.

    So finally I do have a working phone, and I love it. The only one question remains if you get these 3 modes automatically. What I mean by that is that there are several things that are involved - signing in, installing updates, updating apps, restoring the backup, etc. that could be done in a different order. After the numerous attempts that failed, I developed this sequence to set up the phone, and I don't know if it is important or not, but it did work for me:
    1. Reset the phone with WSRT with no SIM
    2. Turn off automatic updates before connecting to WiFi
    3. Turn WiFi on
    4. Sign In with MS account, don't restore any updates
    5. Update all apps in the store (Store -> Check for updates)
    6. Insert SIM
    7. Install all the OS updates one after another (4 in my case)

    I was using unlocked phone but restored a T-Mobile image, which gave me WiFi calling
    01-19-2018 03:11 PM
  23. gvp 1995's Avatar
    All I wrote is correct. But it works on a flat surface. As soon as you put the phone in the pocket (not any pocket, but mostly), it still miss-behaves.

    Here is the WORKAROUND. In the situation you know the proximity sensor will not work, before pressing 'Answer', briefly press 'Power' twice. After this press 'Answer'.
    01-25-2018 11:45 PM

Similar Threads

  1. Why a dual-boot Coship Windows/Android phone is a bad idea
    By WindowsCentral.com in forum Windows Central News Discussion
    Replies: 4
    Last Post: 05-17-2017, 12:45 AM
  2. After CU, bad performance on L950
    By user4545 in forum Windows 10 Mobile
    Replies: 22
    Last Post: 05-15-2017, 01:02 PM
  3. Windows Central = Bad Place for Advice
    By MLXVI in forum General Phone Discussion
    Replies: 23
    Last Post: 05-11-2017, 03:05 PM
  4. Microsoft Surface revenue fell 26% during third quarter, but that's not so bad
    By WindowsCentral.com in forum Windows Central News Discussion
    Replies: 0
    Last Post: 04-28-2017, 10:10 AM
  5. Do you have a bad boss story?
    By HeyCori in forum Ask Dan!
    Replies: 3
    Last Post: 04-25-2017, 01:45 PM