Screen comes on randomlySupport

Last Updated:

  1. Sailing_Nut

    Sailing_Nut Well-Known Member

    OK, I have a really strange thing happening. The screen on my phone keeps coming on for no reason . I set the timeout to 15 sec after noticing this. Now the screen will come on then it goes off after the 15 sec and then comes back on after a few seconds.

    I'd appreciate any suggestions on how to troubleshoot this.

    Thanks in advance!

  2. mruno

    mruno Well-Known Member

    I had the same problem and it turned out to be a very old app that was made for version 2.2. It seems it there was a bug in the app's wakelock. It would start turning on my screen AFTER i opened and then closed it since it was running in the background.
    best way to troubleshoot this is to first verify it is a 3rd party app by booting into safe mode.
    if it doesn't do it in safe mode reboot and start your phone normally and see if it turns on by itself.
    if it still does it in safe mode, you can try disabling some system apps.
    If it doesn't, remember what apps you open and check and see if it starts again.
    if it does it is an auto starting app. You will need to get a list of apps that autostart and disable (or uninstall) them one by one until the problem stops.

    good luck, it took me a couple of weeks to find the bad app.
  3. krouget

    krouget Well-Known Member

    I had the same issue, and it had to do with the pins for the power chord being bent (or something of that nature), which will cause the device to wake as if you had just unplugged it.

    This is why it goes to sleep after the set duration, then wakes up again and again. I *fixed* it by inspecting the contacts, plugging things back in, then carefully removing the chord (while also being more careful about removal in future situations). I found that while plugged, it wouldn't do this, so something was (or wasn't) making contact when it should. Hasn't happened since.

    That's just my experience, YMMV. Good luck.
  4. Tim K

    Tim K Well-Known Member Contributor

    Was about to post this same thing. I've seen a number of users post they were having the same symptoms and it turned out to be a bent pin in the charging port that made the phone think it was being plugged in and unplugged and thus the screen was coming on randomly.
  5. Sailing_Nut

    Sailing_Nut Well-Known Member

    Thanks to both of you for the "bent pin" suggestion.

    I don't think that is the problem because I can unplug the phone and it is well behaved for a while and then it begins acting up after use.

    Still trying to figure out how to use wake lock detector (suggested by someone at XDA) to find out who is turning on the screen. It seems to be a great tool but I just don't understand enough about the terminology to know what I'm supposed to be looking for.
  6. krouget

    krouget Well-Known Member

    That's the tricky part about the pin issue, mine would behave normal for a period after unplugging, then start with the symptoms a bit after (it was inconsistent).

    Certainly run your tests, but I wouldn't rule this out as a possibility, just yet. Does the display turn on while plugged in?

    This should be a big tell; if it doesn't, it's likely the pins, if it does, I'd point towards an application.

    Just keep in mind, that applications which prevent the phone from sleeping, typically don't let the phone time out according to your display duration (which is why they request the permission). The fact that it's cycling on and off suggests a malfunction elsewhere, but again, certainly run your tests. You may want to look for apps like media viewers, maps, browsers, media players, etc. These are all applications which have features that keep the phone awake, from a practical standpoint.
  7. Sailing_Nut

    Sailing_Nut Well-Known Member

    So this may help out in diagnosis. (By people smarter than me! :p)

    I used wake lock detector and found out that it is an Android system process waking the phone up. The process name is modem_usb_suspend_block. In my mind that may have something to do with a bent pin in the USB port. Also the screen does not cycle when the phone is plugged in.
  8. Tim K

    Tim K Well-Known Member Contributor

    I don't think that is your problem. According to this thread that wakelock is related to data transmission via 3G/4G networks.

    Keep in mind that 'wakelocks' are not referring to the screen state. A wakelock means something that has forced the processor to be operating instead of sleeping. We all have these wakelocks, but they don't refer to the screen being triggered. In fact, most wakelocks are with the screen off.

    I don't know how to detect what is triggering your screen to come on, but I'm 95% sure its related to the USB port. As krouget posted, the symptoms vary and can occur with or without being plugged in.

    There are hundreds of people with similar issues.
    krouget likes this.
  9. Sailing_Nut

    Sailing_Nut Well-Known Member

    The reason I suspected that wake lock is that every time the screen turned on that wake lock incremented by 1.

    Thanks for the Google link. It does sound like I am having the same problem. I'll take a look at the port under a magnifying glass to see if the pins seem to be an issue.
  10. krouget

    krouget Well-Known Member

    This is significant, because the pins (or whatever is in there), are *set* properly when plugged in, so everything that should be in contact, is. It's once you remove it, that things are allowed to move out of place, thus causing the display to cycle on/off status.

    My *fix* above wasn't anything professional or scientific (and I didn't feel like disassembling my phone), but it did seem to shift whatever was in there back into place enough to prevent the issue from reoccurring. I figured since it was inconsistent, some contact must have been just a tad off, so that's why I took this route.

    As a compete aside, I can't stand the fact that the display turns on when unplugging the device. It's sad that my current ROM doesn't disable the feature.:(


    Good link, I didn't even think to look there at the time of my problem. That pretty much sums it up.
  11. CRogers

    CRogers New Member

    I changed my power adapter for charging, and the problem went away immediately. I assume it was the result of either drawing too much power, or not enough to charge the phone. Anyway, there you go. Hope it helps! :D

    If your phone is waking randomly while unplugged it may be the phone reconnecting to your wireless network. While searching for the problem I encountered someone who said turning off wifi fixed it. :rolleyes:

Share This Page