yashsingh1/xdaforums huggingface dataset:
[Nexus 7 Q&A, Help & Troubleshooting] Beefheart:
My N7 has a manufacture date of December 2012 too.
[Nexus 7 Q&A, Help & Troubleshooting] lewmur:
Where did you get that date? /About Device on my N7 shows a "Build Date", but that is date the ROM was compiled. I show nothing about a "manufactured date".

---------- Post added at 07:37 AM ---------- Previous post was at 07:33 AM ----------

BTW, have you ever noticed that people who don't believe in Creationism all look like they're smoking pot?:p
[Nexus 7 Q&A, Help & Troubleshooting] lewmur:
Well, 4.2.1 didn't help so it back to "Smooth". Did discover one thing about the chargers. The one from my HP TP is faster. I get 15%/hr from it while it takes the Asus 15%/1.5hrs. Still takes close to 7hr from 10% to 100%.
[Nexus 7 Q&A, Help & Troubleshooting] bftb0:
@lewmur

When you plug the charger in, does the device "cable detect" report a DCP device? (see my prior post)
[Nexus 7 Q&A, Help & Troubleshooting] lewmur:
The lightning bolt appears in the battery icon and in settings, it says the battery is charging. And if the unit is off, the battery charging icons appear for a few seconds. But I don't know what you mean about reporting a DCP device. I checked through your previos posts in this thread and don't see that mentioned anywhere.

edit: Sorry. You meant by looking at the /proc/kmsg file. Unfortuneately, when I try to access that file with Root Explorer, the screen goes blank for a while and then Root Explorer reports an error. What is another way to view it's content?

re-edit; OK. Figured out how to

#cat /proc/kmsg

But right now the battery is fully charged so it doesn't show a charge rate. I'll let it discharge for a while and try again.

re-re-edit: Cable: DCP
[Nexus 7 Q&A, Help & Troubleshooting] bftb0:
Whoops - my bad. The reason that I was asking about the cable detection was that I was wondering if it were possible for a charger to be incorrectly detected as a "SDP" (Standard Downstream Port) rather than a DCP (Dedicated Charging Port). That would current-limit you to only 500 mA. But, that's not what you are experiencing.

After a little closer examination of the USB v1.2 Battery Charging Specification, it becomes pretty apparent that a DCP would never be mistaken for a SDP as the latter requires a live protocol on D+/D-, and a charger that did that would not be cost-competitive with most "dumb" chargers. Although TBH, the DCP charging specification seems to allow devices to be certified as a DCP even though they are barely more powerful than a SDP. Providing just over 500 mA at 2.0V is acceptable behavior for a DCP charger!

The stock kernel does also seem to have CDP (Charging Downstream Port) detection in the SMB347 charger code. Whether or not such devices exist is an open question. Seems like they would only appear on PCs or powered high-speed hubs. (They have a very tight power delivery spec - at least 7.5 W minimum).

Anyway, sorry I'm no help. But I will suggest that if the battery doesn't charge nominally when the tablet is completely turned off, there is little hope that things will be any better with power-consuming processors booted up, nor will any OS flashing make any difference in that case ***

BTW, I've looked at the BQ27541 kernel driver source code - it doesn't appear to do any PROGRAMMING of the controller - it only reads status from that (TI BQ27541) chip at most. While it would be technically feasible for an operating system to write non-volatile changes to the battery charge controller - which would then alter the future history of that device, even if you flashed a different ROM - the driver code does none of that; it only reads data from the charge controller. That is why I am highly skeptical that the OS affects the maximum battery charging rate ***when the maximum rate is already abnormally low when the device is completely powered off.

Have you inquired of Google/Asus whether they regard your results as abnormal?

Just curious.
[Nexus 7 Q&A, Help & Troubleshooting] lewmur:
I purchased the N7 refurbished from Geeks.com. I've emailed their tech support about the situation but I've have yet to hear back from them.
[Nexus 7 Q&A, Help & Troubleshooting] IdeosPower:
return to stock and test charging.
[Nexus 7 Q&A, Help & Troubleshooting] lewmur:
Did that. Still only charging at 15%/hr. Good news is that geeks.com has agreed to exchange it. Sent me a prepaid Fedex label to send the old one back.
[Nexus 7 Q&A, Help & Troubleshooting] ycon:
I just bought mine from OfficeWorks in Australia (32GB WiFi) and it's charging so slowly. Has completely ruined my experience with it.

I've rooted my device, installed multiboot, and a custom kernel (Kernel w/ kexec-hardboot patch (stock 4.2.2)). Could any of this be the cause? I can't be sure, but I think that before I rooted it it still took a long time to charge. I'm using the Stock rom

For example, today it took me 4 hours to charge from 38% to 50%

So far I've tried:

* using the stock USB cable plugged into my computer, and then plugged into the stock charger. Both were equally slow.

* a random spare USB cable, and a different charger, but it is the same.

* charging with it on standby, and off, and still the same
[Nexus 7 Q&A, Help & Troubleshooting] bftb0:
@ycon

If it charges at only 4% per hour with the tablet turned completely off (not sleeping - off), you have a hardware problem.

If it is completely off, the installed software does not make any difference (how could it, if it is not running?)
[Nexus 7 Q&A, Help & Troubleshooting] LauraSakura:
I'm having this issue too. I left my Nexus plugged in to AC and turned off... After 12 hours it still wasn't full. Didn't do this before 4.2
[Nexus 7 Q&A, Help & Troubleshooting] goodbuoy:
Same thing with me

I experienced the same problem with my Nexus 7. What I did is returned it to ASUS for repair. First they did is replaced the battery. But after a few weeks, the problem returned. So I have ASUS checked my device again but this time with my AC charger and cable. They didn't find any problems with the charger and cable. But what they did is they replaced the battery, the board, and an IO cable between the microUSB port and board. Now, I am currently charging my device for the first time since I got it from ASUS. It seems the charging is normal with my device on sleep mode. It gained 10% for I think 20 mins.
[Nexus 7 Q&A, Help & Troubleshooting] apis10:
My nexus7 won't charge when it's switched off but charges normally when on.

There must be something wrong with kernel settings for offline charging
[Nexus 7 Q&A, Help & Troubleshooting] WalterCool:
If someone have a PS Vita, try using this charger with a microUSB cable and profit. 2-3hrs and it's charged (turned on). PS Vita charger is 2mAh with standard voltage.
[Nexus 7 Q&A, Help & Troubleshooting] md1008:
Mine is slow too, but the battery last forever on a full charge so it all evens out I guess
[Nexus 7 Q&A, Help & Troubleshooting] asrdias:
I was using a custom rom v 4.2.2 based on Cyanogenmod and had this slow charging issue. It would take forever to get my Nexus 7 to 31%

I installed Factory Rom 4.2.2 and root it.

Now charging is very fast. Maybe 2 hours to get it from 10% to 100%

I am guessing there's something on some custom roms that screws the charging. Maybe some custom governor settings or power settings. Have no idea...
[Nexus 7 Q&A, Help & Troubleshooting] ReiverBlade:
i use a N7 8gb under 4.2.2 and it charge real quick (i brought it recently it was under 4.1.2 and did a OTA update)

i guess its more battery provider dependant than software (im using pure stock so it might be custom rom related tho...)

normal AC charger in the package is a 2a no? at last mine is a 2A 5v ... (i think you meant 2A not 2mAh) so basically ps vita has the same charger as the N7 (if someone has another Amper rating let me know xD )
[Nexus 7 Q&A, Help & Troubleshooting] LauraSakura:
Unfortunately mine charges slowly no matter what ROM I flash. I have the original wall plug but a different USB cord. I've tried with other cords with the same result. It charged fine for months then all of a sudden started charging super slow. I want to say it was around when I went to Android 4.2 but it might just be a coincidence. At this point I just figure my device must have a problem and I'll just have to deal with it. I think I'm outside of the warranty window by now and I assume I voided it anyway.

GNex // Toro // RootBox // AK exp // Hue
[Nexus 7 Q&A, Help & Troubleshooting] ReiverBlade:
Oh Well i will keep my N7 stock...since its pure Android base i dont see the need to use a custom rom...:rolleyes:

More now, as i see many custom rom user have charging problems xD
[Nexus 7 Q&A, Help & Troubleshooting] Gulfcoastowl:
I did work for me

It did work for me. I tried changing the direction I plug in with original wall charger. Before it used to take 8 hrs to completely charge and now almost 1% every 70 seconds. I charged it completely in 2 hrs. earlier I was using a usb equipped surcharge protector thing. So now on my original wall charger i marked the correct direction of the charger to pin this way all time. I tried it for 2 full charges and fully charged in 2 hrs. I am using 4.2.2 and i had it fine until i started using a different unit(usb wall surcharge protector which was close to my bed) and now changed to original charger. I think it is worth for all u guys giving it a try with polarity and different sockets and may be original charger
[Nexus 7 Q&A, Help & Troubleshooting] PalmerEldrich:
Glad that worked out then. Those kind of problems are scary.
[Nexus 7 Q&A, Help & Troubleshooting] subhishine:
Agree

I agree with this..

it just happened to me today and the last night, my nexus 7 is still charging for about 10h (63%), then I switched/reverse the polarity of the charger then I got the fast charging.

Fast charging mode= the charger is warmer than a normal state.

Slow charging mode= the charger is not getting warmer.
[Nexus 7 Q&A, Help & Troubleshooting] ReiverBlade:
I tested charge with ac adapter 13% to 100% 1h45, weird... Still nous custom ROM just 4.2.2 stock root.

If you use custom ROM is there a possibility, that you messed up with the batterie status and calibration?

Or you have bad habit of plugging the N7 to the charger before 15%- battery

Also I never look how i plug my charger and it charge same either way.
[Nexus 7 Q&A, Help & Troubleshooting] divvykev:
Same problem but battery drain too

Also suffered from slow charging but also severe battery drain caused by Android OS and am wondering if these are linked.

I have a Nexus Wifi 16G and an Xperia Arc LT15i and when I use JB Rom on the phone then I get the same issue which makes me think its one of the google apps which is causing the OS to continously wake and thus cause drain. Dont get it on GB.

What I have found though with the N7 is that if I use Battery Calibration from the AppStore when it eventually gets to fully charged then charging becomes normal for a while. I have suffered this issue with several Roms including stock.

Weird eh.

BTW also tried different cable, wall sockets, usb adapters.

I know this doesnt offer answers but I cant help thinking that the big battery drain and slow charging are linked in some way.
[Nexus 7 Q&A, Help & Troubleshooting] najaboy:
Sigh. Battery stats and "calibration“ are a wives tale perpetrated by a gross misunderstanding of both Android and how lithium polymer batteries operate.

Also, you may want to study up on batteries. What you term a "bad habit" is actually more like a best practice.
[Nexus 7 Q&A, Help & Troubleshooting] LauraSakura:
I can confirm this has helped me as well. Plugging the adapter in the opposite way has greatly increased my charging speed

GNex // Toro // CodeX // AK exp // Hue

---------- Post added at 01:05 PM ---------- Previous post was at 01:02 PM ----------

On this note, Anyone dealing with excessive battery drain should try the app "better battery stats".it tracks wakelocks so you can see any apps or services that are preventing your device from remaining in deep sleep. It's great for diagnosing excessive idle battery drain.

GNex // Toro // CodeX // AK exp // Hue
[Nexus 7 Q&A, Help & Troubleshooting] Coyote0420:
[fixed]Reverse the Polarity!

To think it was such a simple thing.. I've tried for 3 months to get my 7 to charge while plugged in AND operating.

Before flipping the wall adapter... seriously that kills me... it would die even while charging with only wi-fi and basic use. It had charge with the screen off but would take 12+ hours from a dead state.

And out of all the different roms, battery manager apps, cables and 4 different wall adapters nothing seemed to improve it. Although a screen dimming app (Screen Filter) actually slowed the discharge when I set it to about 25% brightness. But since the begining of writing this post it's went from 5% to 12%, all while running the CPU at full.
[Nexus 7 Q&A, Help & Troubleshooting] jastonas:
It appears your help, helped many people! You should edit your post and put in bold the part with the fix :)
[Nexus 7 Q&A, Help & Troubleshooting] nhutquang972012:
Added the solution to first post :D
[Nexus 7 Q&A, Help & Troubleshooting] fnixirix:
hi guys.. my charger socket is 3pin adapter n my wall 3 pin plug socket as well. any idea how to reverse / flip it ???
[Nexus 7 Q&A, Help & Troubleshooting] najaboy:
The flipping of the plug as a solution is a post hoc logical fallacy. There is something else going on.
[Nexus 7 Q&A, Help & Troubleshooting] bftb0:
I'm glad you said it - folks are getting tired of me always being the contrarian. ;)

I poked around a little bit and found that it is possible to have a (quite small) DC bias present on an AC branch circuit due to unrelated loads (for instance loads that do half-wave rectification) on the same branch. So *in principle* you could tell one polarity from the other using only a two-terminal device if that condition was occurring. This condition (DC offset) actually can very negatively effect the amount of primary winding currents in transformers connected to the AC mains. But even in this case, the effect is deleterious in either polarity - not just one polarity versus the other.

For completeness, I flipped around my AC charger (that previously was charging my tab from less than 10% to 100% in about 150 minutes) and charged my tablet from 6% to 100%. How long did it take? 150 minutes.

As you say, post hoc fallacy. If there is a penny on my desk showing heads, and I throw it once in the air and it lands showing tails, it is fair to report that experience. But it is not reasonable to conclude that it will always come up tails on every subsequent throw.
[Nexus 7 Q&A, Help & Troubleshooting] Nate2:
Same slow charging problem here too :(

I'm still on Android 4.1.2 on my rooted, stock Nexus 7; never had 4.2 or custom ROM.

Always using original Asus AC USB adapter and the short charging cable it came with, charging at the same location in my house.

I never had a charging problem for the first couple of months (full charge in about 2 to 3 hours).

Now, it is taking about 12 hours for a full charge.

I surmise that it is a Google Services (Framework?) update (either via a Google Play or Maps update, sometime over the past year) that caused this problem.

Also, my Nexus 7 used to be able to sleep soundly for 6 days straight; not anymore... it wakes up and I have to manually force stop Google Services to get it to go back to sleep.
[Nexus 7 Q&A, Help & Troubleshooting] AndDiSa:
Facing similar problems currently.The last changes to the device were only the official Google Play Store / Hagout / ... updates, so I suppose it's related to that. Btw. currently Google Services are using more then 50% of my battery. :(
[Nexus 7 Q&A, Help & Troubleshooting] jastonas:
I returned mine. Waiting for a replacement or a fix from asus.
[Nexus 7 Q&A, Help & Troubleshooting] SixSixSevenSeven:
Looks like I am making a warranty claim for a 9 hour old device. 25 minutes it has been on ac power and sleeping. Its charged 2% on the 4.2.1 kernel using the stock 2A charger (UK 3 pin so the utterly ridiculous suggestion of reversing polarity doesn't apply).

According to the battery info screen 75% has been consumed by the display which seems a bit excessive seeming as I am on minimum brightness.

See how it goes overnight but not the best start
[Nexus 7 Q&A, Help & Troubleshooting] mattyman:
Hey guys,

How many of you having the charging issue still have USB Debugging turned on?

I've had the issue since I rooted the device. I still had USB debugging turned on so I switched it off. I might be jumping the gun a bit but I think it's charging normally since doing so.

Matt
[Nexus 7 Q&A, Help & Troubleshooting] Nate2:
My USB debugging has always been on since the early days of my N7 when charge rate was fine. But I will try turning it off now and see if it makes a difference in charging, and report back.

Thanks for the suggestion.

Edit: Slow charging, even with USB Debugging turned off: 15% to 75% in 6 hours. Fully charged in 8 hours. If there was an improvement, it was marginal :(
[Nexus 7 Q&A, Help & Troubleshooting] nicetaco:
Use the bloody charger that came with it!
[Nexus 7 Q&A, Help & Troubleshooting] jpm168:
Been using the N7 for about 2 weeks and had the slow/non charging problem last night. After swapping polarity and cables it seems the problem is the original cable that it comes with. It appears plastic cover of the cable does not expose enough of the metal contact so the cable does not seat all the way in properly into the usb port on the tablet. Swapped a cable with a shorter cover, hence longer contact is exposed, solves the problem and it charges quickly right away.
[Nexus 7 Q&A, Help & Troubleshooting] jfmcbrayer:
Has anyone who has been having slow charging tried the dock? If so, do you still have the problem? I ask because I am suspecting that the problem may be, for many of us, a loose USB jack that is not guaranteeing a good connection for charging -- see this thread on reddit (I am not the OP and have not yet commented on that thread). I have not yet bought a dock, but I do find that the only charging cable that reliably works for me is the much beefier one that came with my wife's Archos 70b tablet. It could be the cable itself, but I'm thinking it's actually the slightly heavier connector that's ensuring a better connection.

So, anyone using the dock and still having slow charging?
[Nexus 7 Q&A, Help & Troubleshooting] PsychoMcSatan:
Both me and my cousin had these problems with messed up charging and sure enough, once my dock arrived the thing charges fine. In fact, it convinced my cousin to get a dock as well.

With some experimenting we found that some cables definitely charge much better than others and I've found a Samsung branded cable that seems to charge as fast as the dock. For both me and my cousin, the stock Asus cables flaked out after only a few weeks of use.

-PMS
[Nexus 7 Q&A, Help & Troubleshooting] jfmcbrayer:
Thanks for the response. I've tried a number of cables of different brands and gauges, with my stock charger, and only one of them has helped.
[Nexus 7 Q&A, Help & Troubleshooting] jpm168:
I'm pretty sure the stock cable is definitely cr@p. Tried using that to charge other things with a computer, and the lightest touch would cause it to disconnect/reconnect. Funny enough when I first searched about this problem, it led to the google page that suggest you to always use the stock cable which would then lead you down the wrong path.... The design of the recessed usb port doesn't help either, as some cables might not be plugged in completely.
[Nexus 7 Q&A, Help & Troubleshooting] Nate2:
I'll try my original Motorola cable from my DroidX. I wonder what could have happened to my original Asus cable...

Thanks for the suggestion.

Edit:

My Nexus 7 now charges from 15% to 100% in about 3 hours (like it should) with the Motorola cable! So the Asus cable internal resistance must have somehow increased over the past 6 months, causing it to slow down the charge rate?

With Motorola cable:

After 1 hour: 45%

After 2 hours: 75%

A little after 3 hours: 100%
[Nexus 7 Q&A, Help & Troubleshooting] jfmcbrayer:
I experimented with the heavy Archos cable (which I know charges with the Archos charger), and the stock Asus charger. No dice. So in my case, it may actually just be that the charger has crapped out after a few months. Now to try Archos charger with the Asus cable and a generic cable...
[Nexus 7 Q&A, Help & Troubleshooting] someone755:
I experienced the same thing as you guys. As somebody already said in the beginning, it's worth checking the battery connector. That is, remove the back cover, lift the battery and disconnect the connector for a minute or two. Then put it all together and it should be working perfectly!

Did wonders for my grouper. And no, it isn't a firmware or cable or charger fault. At least not in my case...

Have you guys never had a phone with a removable battery? Back in the old days, if anything was wrong with the battery life or charging, all you had to do was remove the battery for a few minutes :D
[Nexus 7 Q&A, Help & Troubleshooting] bsoplinger:
I bought the HP Touchpad charger mentioned in the accessories subforum here and one of the monoprice USB cables mentioned in the same thread (I think or perhaps another one on charging issues) and went from a typical charge rate when docked (using the factory cable and charger) of 450ma to as high as 1.8 amps using the new stuff. So charger and cable do make a difference.

Sent from my Nexus 7 using Xparent Purple Tapatalk 2
[Nexus 7 Q&A, Help & Troubleshooting] yeubacgiang:
Now im experiencing the same problem, did anyone find solution for this?
[Nexus 7 Q&A, Help & Troubleshooting] jfmcbrayer:
I don't think it's a single problem affecting everyone, but a number of different problems with the same symptom (slow charging, possibly discharging when plugged in and awake).

Having been through the troubleshooting process on this, here's what I'd recommend, more-or-less in order.

Try a different cable. A damaged stock cable is both common, and cheap to replace. If you want to completely rule out cable problems, try a Monoprice ferrite-core cable.

Try a different charger; it seems to not be uncommon for something to go wrong with the stock charger. Unfortunately, even most chargers that claim to be rated 2.1A don't seem to deliver enough current. Chargers from the HP Touchpad and various Samsung tablets seem to work. My Archos 70b charger works, even though it only claims to deliver 1.5A.

Pop off the back, pull the battery cable, wait a few minutes, and plug it in to make sure it's seated snugly. This fixes some other charging-related problems (see stickied thread for details).

If all else fails, you can RMA it. It's possible something's wrong with the USB charging port or the charging circuit.

In my case, it was almost certainly the stock charger that died. It will only deliver the needed level of current when plugged into the outlet at a very particular angle, and it's only possible to be sure it's inserted right by using CurrentWidget. I think this is the source of the urban legend about "reversing the polarity" -- some people's chargers need to be plugged in very carefully, and turning it around gets it properly seated.
[Nexus 7 Q&A, Help & Troubleshooting] ianmedina:
Guys.... i have a friend from asus who told me that if you have slow charging problem you gotta do this.

use the stock asus usb cable

plug it in to your computer and make sure it's charging via USB, then just wait for 3 minutes then

unplug it, charge/plug it in via AC using stock asus 2A charger. then wait for atleast 5-8 mins

then check it if it's starts to charge quickly. =)

Hit thanks if it's working.
[Nexus 7 Q&A, Help & Troubleshooting] shab_2008:
Hi there ,

I faced the same problem. my device charging time took 5 hours from 30% to 100% . For the next time , I replaced the cable with another one and the charging time took 2 hours and 53 minutes from 10% to 100% !

Be happy.
[Nexus 7 Q&A, Help & Troubleshooting] jfmcbrayer:
What did you use to produce those logs, Nate2? I would find that useful.