Nexus 7 never goes into deep sleep

[CBF1]

The new Nexus 7 was my first tablet, so I didn't really know how much battery to expect when I turned the screen off, but it did feel like the battery drained too quickly. After going to bed and waking up I'd find around 20% of the battery gone. I've had the tablet for a week and a half and I decided to investigate more into the issue and saw this thread http://forums.androidcentral.com/go...822-omg-thing-has-battery-just-wont-quit.html which indicated something was wrong.

I downloaded Wakelock Detector, BetterBatteryStats, and CPU Spy and they all confirmed that my tablet never goes into deep sleep (always 0% deep sleep, 100% awake)) and gets wake locked very often. I guess often enough so that the tablet never has a chance to go into deep sleep. I went and did a factory reset, downloaded the 3 apps and the other default apps were automatically updated. The problem still happens.

So far I've isolated the wakelocks to AlarmManager and ActivityManger-Launch. Wifi is turned off, Location access is off and I even deleted my account so nothing would get synced. I'm confused because it would appear that this is a software issue. However, other people don't have this problem out of the box while my tablet is like this after a factory reset. Could it possibly be hardware related?

 

[Aquila]

Have you tried singing it a lullaby?

Just kidding. I lose 1-2% while I'm asleep 5-7 hours. It's possible there is something wrong with the battery. If you can't get it solved with software (factory reset should have done it) then you may want to call Google's support and have them replace it.

 

[hillwoman]

I had this issue with my first gen nexus 7. And while Wakelock detector didn't actually tell me which app it was, it did tell me that it was a 1013 audio issue. I find that it's usually a game that for some reason doesn't turn off the audio when it exits (at least that's what I'm guessing is happening, because the app isn't running, but audio still is). What are those three apps that you put back on?

 

[CBF1]

The 3 were the battery apps Wakelock Detector, BetterBatteryStats, and CPU Spy.

I'm trying to do another factory reset except this time I turned the screen off as soon as the welcome screen came on so I didn't even choose a language or get onto wifi or anything. The battery was at 70% (was at 90% the night before) when I turned it off so we'll see what happens in a couple hours.

 

[CBF1]

Well, after 3 hours and came back, connected to wifi, signed in, and found that there was only 59% battery remaining, so something was going on in the background even though I was just at the Welcome screen and had turned the screen off. Looking at the battery usage, most (over 80%) were from Android OS and Android Services which I'm guessing was AlarmManager and ActivityManger-Launch.

I bought it from Amazon and I think their return policy is pretty generous so I might start that if I can't get this problem resolved in a few days.

 

[DeepSeaGoddess]

I started using DS battery saver on my first gen nexus 7 when this happened on it and that cures it....it put it to sleep. So I have it on the new 2nd edition too. I paid for the pro version to be able to do custom sleep settings. Works great for me.

Posted via Android Central App

 

[jerrykur]

Before sending it back reset it factory, DO NOT load any of your apps, and give it a try. If that works then you know it is an app and you will have the same issue on the replacement unit.

 

[CBF1]

It's not any of my apps, as the battery drained quickly after factory resetting and turning the screen off at the welcome screen.

I've disabled and force stopped so many things that I can't believe this is still happening.
Running services: Settings, DS Battery Saver, Google Keyboard
Cached processes: CPU Spy, Wakelock Detector

On top of that I disabled almost every app. All that's left is Calculator, CPU Spy, DS Battery Saver, Settings, and Wakelock Detector.

 

[Aquila]

It's not any of my apps, as the battery drained quickly after factory resetting and turning the screen off at the welcome screen.

I've disabled and force stopped so many things that I can't believe this is still happening.
Running services: Settings, DS Battery Saver, Google Keyboard
Cached processes: CPU Spy, Wakelock Detector

On top of that I disabled almost every app. All that's left is Calculator, CPU Spy, DS Battery Saver, Settings, and Wakelock Detector.

Three of those five things on the "all that's left" list would have been my top suspects.

 

[CBF1]

I actually didn't disable everything. There was an 'All' tab further to the right in the settings>apps, so I went an disabled as much of those as I could, but it was still the same with AlarmManager and ActivityManger-Launch constantly wake locking the tablet (twice a minute if I read Wakelock Detector correctly). I just uninstalled Wakelock Detector and CPU Spy (and DS Battery Saver was uninstalled earlier) and will see what happens in an hour (battery currently at 30%).

After that I'll recharge, do a factory reset, not install any apps, and see if the tablet goes into deep sleep based on battery used (right now it's around 2-3% an hour with the screen off).

 

[Aquila]

right now it's around 2-3% an hour with the screen off

Yeah if you can't get it narrowed to an app, I'd definitely suspect a faulty battery. Mine is literally closer to 1% every 4 hours of idle.

 

[CBF1]

Can a faulty battery cause wakelocks like AlarmManager and ActivityManger-Launch? The battery seems pretty good when watching videos like around 10% for an hour. That's why I'm so confused. From what little information I've read, these wakelocks are caused by some app trying to do something, but even when everything is disabled and after a factory reset these wakelocks still happen.


Edit: It's not looking good.
I charged to 85%, did a factory reset, got onto wifi, skipped entering an account, turned off location stuff, turned off wifi, and after 38 minutes the battery went down to 82%. Android OS was 43% and Android System was 31% so it's probably AlarmManager and ActivityManger-Launch again.

 

[CBF1]

I'm going to try to exchange it. Went to bed and the battery was down into the 60s% when I checked it. Then I put it into safe mode and 2% was drained in a bit less than an hour. Android OS was using over 70% of the battery.

 

[stkorn97]

I'm going to try to exchange it. Went to bed and the battery was down into the 60s% when I checked it. Then I put it into safe mode and 2% was drained in a bit less than an hour. Android OS was using over 70% of the battery.

Since you arent doing any other apps most the time, the OS will eat a huge % of the battery cause its the only thing running and should have a high %. Its seeming like you have something else sucking battery life, if you reset it and left it running stock without apps, Id assume its battery issue itself.

 

[CBF1]

If I read Wakelock Detector and BetterBatteryStats correctly, the tablet gets wakelocked by AlarmManager and ActivityManger-Launch over 100 times an hour so the tablet never goes into deep sleep. Now the fact the tablet never goes into deep sleep after multiple resets and settings really confuses me since no one else seems to have this problem. I mean, shouldn't my software be the exact same as everyone else's? If so, then I can only conclude that it is a hardware issue causing these wakelocks. I don't really know much about wakelocks, but I thought it was only a software thing.

 

[rxnelson]

Have you tried airplane mode? I had an Android tablet and phone that absolutely hated my router. It kept it almost constantly awake. Maybe even with WiFi off that new scanning feature under advanced is still doing location stuff in the background?

What about qi charging? I've heard N4 owners complain it can cause a wakelock.

The only other thing I've got is to turn off touch sounds. That recently plagued my nexus 4.

Whatever it is it isn't normal.

Left mine home today after charging overnight.

Sent from my Nexus 7 using Tapatalk 4

 

[CBF1]

No luck with airplane mode.

Now I have another question. I bought the Poetic Strapback case and it works fine. But from this post http://forums.androidcentral.com/google-nexus-7-2013-accessories/299558-cases-5.html#post3000584 and the reviews on Amazon, it seems everyone's tablet turns off while folding it back. Mine doesn't. So it is possibly my hardware issue is with the magnet?

 

[rxnelson]

Can you stick a magnet on the device and make it shut off? Maybe the case is faulty?

Sent from my Nexus 4 using Tapatalk 4

 

[jerrykur]

Something seems wrong with the case. Why not remove it for a few hours and see if it has an effect.

Posted via Android Central App

 

[CBF1]

I just briefly used the case and the problem persisted.

Closing the case the normal way turns the screen off, but folding it back to use the strap does not. Maybe there are variations in the case magnet or something is wrong inside the tablet.