Nexus 7 (2012) Wont Turn On? - HOW TO: Jump Starting the Flatlined Battery
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- เผยแพร่เมื่อ 2 ต.ค. 2024
- Watch in HD! Read description if you want to skip ahead some...
WARNING: This video is for the 2012, First Generation Nexus 7. While this procedure will work on various devices, including the second generation Nexus 7 (2013), your process for opening your device will vary. Also do some research before grabbing the pry tool!
This video is a little lengthy...but I wanted to show the steps I took to make sure that it wasn't a simple problem. I.E. holding the power button, checking the battery connection, using the power cord, etc etc.
If you don't want to see my thought process, or hear some of the explanation before the fix, skip to 7:20 to see what I did!
This might work with other devices that have flat-lined like this tablet! DIY and get your device working again!
Thanks for watching! Any questions or comments feel free to post, and please subscribe!
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Holy shit! This really actually works! My Nexus 7 (2012) died a few years ago after sitting in a drawer for too long and this brought the battery back to life! I have 0 electrical experience and no multimeter to test anything, but decided to try it anyway (despite the fire risk if something went wrong). I stripped the cable with some scissors and left it charging with the modified cable for about 20 minutes. Lo and behold, it turned right on after nothing else worked!
Thanks again for making this detailed video. I greatly appreciate it and you made my day.
Glad it helped!
My battery was showing zero volts at the pins. I used a USB lead and some telephone wire to go into the openings on the battery connector. I used an iphone charger to provide the juice to the USB. I put the battery into a metal enclosure outside just in case there were any fireworks. Aprrox 5 mins on charge brought it up to 3 volts. Replaced battery into Nexus, attached charging lead and started charging straight away. I had also opened the tape on the battery and saw that the paired wires were soldered together at the battery. Good job. Thank you.
Thanks for the idea. I tried something else, which I read somewhere years ago. I plugged and unplugged the USB port in and out continuously for a second at a time, maybe 30-50 times. The battery then started working and charging. I do not know the exact reason but apparently the tablet gets a charge for the first second and there is a mechanism to stop charging right after the first second. So if you plug and unplug continuously at the end it is charged enough seconds to be able to be charged continuously. I had the same problem with a BlackBerry tablet and it worked there as well. To avoid damaging the tablet I plugged and unplugged the hub end of the cable.
+apierrat Awesome!! That would be a great alternative if it turns out to work for others! I did try to plug/unplug mine, but not nearly as many times as you did. So maybe I should have done it a few more times. Good tip on not unplugging at the tablet...the MicroUSB would probably not appreciate that. Thanks for commenting!
This comment just got me going! Thanks! Been sitting here for years in a drawer and decided I wanted to put CyanogenMod on and see what would happen (it's basically been a brick for years). Now to see what happens!
Thank you! I believe this just jump started mine, as I can now see a dead/charging battery image flash on the screen.
I have tried both the method shown in the video and the method described in the comment here. Both have worked for me.
The reason you have 2 reds and 2 blacks that are paired is likely simply that having pairs enables more current to be passed by what is quite a small connector for a battery of this capacity. Stories elsewhere of 2 cells in the pack are wrong. No one does that unless in series to make a 7.4V battery.
There should be more warnings here about your charging method. Accidentally shorting the battery or charging it at 5V from USB for too long may lead to a fire. But charging from USB for 20 mins or so is OK if battery is indeed flat. Problem will come if it is actually fully charged without the viewer realizing it to its >4V max and someone tries to add more to make it 5V. That could start a fire. To be safe check the voltage is less than say 3.6V before you start charging it. And never leave this unattended or on all night. And check what I say is right before proceeding.
Ideally one should use a 4 to 4.1V charge source but these are not readily available.
You are right. In fact if you measure resistance between these two reds and blacks, you get straight zero, so need to charge inner or outer pairs separately.
I replaced a cracked screen (the unit did charge and turn on with it in place) and cannot get it to boot up. I tried all the tricks I could find including jumping the battery. Still nothing. I checked the battery and got 4.15 on my multi meter for each of the two cells. Swapped the old screen back in to see if I had a bum replacement screen. Not a thing with the old screen either. Any more ideas on why it won't start with a charged battery and new screen?
+Marc Riddick Hmm...bad power button maybe? Check the ribbon cable for the power button, make sure its seated. If it is, use your multimeter to make sure the button is closing the circuit. You could also just trace it to the main board and jump the two points to see if it powers up. In my video, you can see the two wires that I have added...those are actually going to the power button solder points. So you can see where about they are. Failing all that, Im at a loss. Im not a pro with LiPo batteries...can you have enough voltage, but not enough amps to run it? Sort of like losing some cells in a car battery? Measure 12v, but drops to nothing when cranking?
I had the same problem, I removed the battery, checked the voltage, it was less than 3 volts then I had lithium ion battery charging circuit, I charged the battery using that overnight and checked the voltage and ot was around 4.3 volts....
And I plugged the battery in tablet, tried to boot it up and *disappointment*...
It wasn't booting up :(
Still its not booting
After 6 years, I could finally use my old tablet because of this.
Ditto
No luck unfortunately. Made a very nice lead with crocodile clips attached to an old stripped down USB lead. All good there with a tested 5V coming from the charger. The old battery in the unit was completely dead and did not register any voltage at all. While I was able to get it partially charged it was unable to hold a charge. Swapped out battery for a 'new' one which I measured at a little over 4V. However no amount of button pressing, or combinations thereof, managed to bring the device back to life. A fiver wasted on a new battery, but it could have been worth it. Sadly not. I guess something else is wrong with it, perhaps the screen, a failed chip, dry joint etc. Nothing lasts for ever, I guess, but the Nexus 7 was the perfect size for reading books and watching the occasional TH-cam clip. March 2023.
Thanks!
Worked perfectly. Tablet had been sitting for a few years. Changed charging port also.
This method of jumpstarting it is really smart! It worked for me perfectly, but not wanting to mutilate any USB chords, I used 3 AA batteries (1.5V each) linked up to get 4.5 V. But it still worked! Great idea!
+Alexander Ng Hey Alexander...thats a GREAT idea! I didnt think of that...but I already had like 40 mutilated cables laying around so it just made sense to use one haha. Thanks for watching and commenting. Glad it worked for you!
I just tried what you did,same dead battery 2 engineers could not do it,and hay presto it worked. your amazing
Awesome :) Glad it's going again for you!
Can't thank you enough keep the tips and video's going
Found my Nexus being set aside for more than 5yrs. Couldn't get it to charge. Couldn't get it to turn on. Followed the jump start instructions and got it up and running in
Awesome! Glad another device is getting some more use!
I can't believe you had a multi-meter right there the whole time and not once checked the battery voltage?? If you had I'm sure you would have found the voltage to be below ~3V (from not being charged in so long in your case) which is too low for a LiPo so the built in LiPo charging circuit deems the battery to have failed and does not attempt to charge it for safety reasons, in case the battery has become faulty. All you are doing with this 'fix' is raising the battery voltage high enough so that the built in charging circuit sees the battery as safe to charge again.
FYI this is a fairly common 'fix' in R.C. circles for liPos that were not disconnected/turned off and have been allowed to get too discharged and a LiPo charger will refuse to charge it, in this case the charger is switched over to NiCad or NiMh mode which doesn't care what the battery voltage starts at and the LiPo is then charged at low current until the voltage has risen a little above 3V and then the charger is switched back over to LiPo mode and the charging can continue normally.
+Awynn0 Pretty sure I checked the voltage. I knew it was low...too low for the circuitry to kick in. Im sure there was reasoning behind not allowing the battery to charge after a certain voltage. And I know LiPos have a "min voltage" you should let them drop to. But I have heard of people giving up, buying a new battery and having the same issue with the new battery. Or...buying a new in box Nexus that is dead right off the bat...from sitting on the shelf. They arent bad...just need a little kick start to get them moving again. Then they work great. The one I jumped still acts like new. Im curious as to why you are putting fix in " marks? It does fix the problem...no? Pretty sure that classifies is at as a bonafide fix. I have heard of the RC community doing this. But my RC experienced ended with Ni-Cad haha. Just getting into NiMh and quickly realizing I should skip it and move right to LiPo, since thats what all the cool kids are doing. Thanks for the comment!
What could be wrong if the battery trickle charged at 3.7v 0.5A and after approx 10 mins the battery was charged to 3.7v but tablet is still not powering up.. usb current meter shows 0.44A 5v draw
I was skeptical but it did work. The battery was giving 3.2V after a few years in the junk pile. 5V is actually a bit much for a lithium battery. They typically don't want more than 4.2V. A normal charge would be with a fixed current at first and then switch to fixed voltage (4.2). I tried with my lab power supply and couldn't get the battery to take more than 300mA, with 4V up until 5V. So I left it on 4.2V for like 10 minutes, plugged it back (the cable had quite some slack, so I didn't need to detach the actual battery from the tablet) and it started charging normally... The battery is probably mostly junk now but this tablet has a great feature: it has an NFC chip than can actually read mifare 1K chips.
Note: after "kickstarting" the battery and plugging on USB, it was only drawing 0.43A, which is very low for a tablet.
was really skeptical about this, my nexus was back of a drawer unused like 2 years.. Teared usb cable down with scissors and teeth, and used sawing needles to connect. Worked like a charm, thank you good sir!!
I was skeptical too! Figured what did I have to loose if I was about to throw it in the trash. Mine is still going! Thanks for watching and thanks for the comment!
...and another thanks from 2023!! Found a couple in my pile, one took a charge no problem but the second one was just flashing back light when you plugged it in. Pulled the battery, put some old resistor leads into the connector and clipped on 5 volts from a breadboard power supply for 15 minutes. Re-installed the battery and it started charging just fine. 👍
I just found my old Nexus and needed to do this to bring it back to life, very impressed that it worked. I used a portable USB battery so I could do this outside away from the house, but everything went smoothly and now my Nexus is plugged in and charging normally.
Simply put, if the battery voltage drops below 3.2 volts the protection circuit in the tablet takes that as NO battery, if left too long uncharted normal decay causes this, by force charging for a few mins can bring the voltage of the battery above 3.5 volts, protection then ses it as a good but discharged. And will in most cases start charging.
Bingo!
Absolute legend cheers mate. 30 mins on the outside red and black ports. used a pair of safety pins and tied the cables to them. 30 minutes of that got me 40% battery. had the device in a drawer for a few years and can breathe some life back into it. any ideas on what i should use it for? :)
FWIW, the correct way to recover a lithium ion cell that won't charge is to trickle charge it VERY slowly - i.e. at a very low current, until it reaches at least 3V. We're talking 50mA, not a lot more.
Once it passes 3V (sometimes a bit more if it still won't cooperate) you can usually just charge it normally. The problem is that chargers refuse to charge a cell that's too low - in this case, we're talking about the charge circuit built into the tablet, not the USB wall wart that powers it. The way around that is to charge the cell at a very low current until it gets to a voltage that the charger will accept as a working cell.
The trickle charge is partly for safety reasons, but also because a really flat cell can be damaged by charging it at a normal rate.
Interesting video though. Thanks.
TooSlowTube Great info! I agree ideally trickle is the way to go. But I doubt most folks have the ability to trickle charge at this level, unless they have a wall wart that outputs that low of an amperage. The wall wart isnt providing any current over what the battery normally takes during charging through the circuitry, its just getting it direct to the leads for a short period to bring it over that low voltage condition. Then the devices power handling can take over. This is certainly not the way it is show in "the book", but most folks would be throwing the device away at this point. Or spending a bunch on a new battery. Thanks for the comment though! Im sure the viewers will find it helpful!
Agreed. It's worth trying, at that stage.
The simplest way to trickle charge is just to use a resistor in one of the wires from the power supply to the battery (which costs pennies).
Assuming the battery was at zero volts, and a 5V supply, a 100 Ohm resistor would give you 5/100 = 50mA. That drops as the battery voltage goes up. By the time it gets to 3V, probably ready for the charger, you'd be getting (5-3)/100 = 20mA, so it would be taking longer.
If you had a volt meter (ideally), you could switch to a smaller resistor, after you see it get to 2V or so - e.g. a 47 Ohm resistor (a common value) would be giving 63mA at 2V = (5-2)/47, dropping to about 43mA at 3V - I've used that trick with lipo batteries for RC models.
On the other hand, the battery has a protection circuit strapped to it, in this case, so maybe it's clever enough to do all that itself :)
I tried trickle charging by using dc power supply set to 3.7v 0.5A after approx 10 mins the battery was charged to 3.7v but it still not booting up, battery is holding charge and usb current meter shows 0.44A 5v draw.. what else could be wrong?
thank you sir it really works
+acerobert padilla Glad it worked for you!
Yep this worked; effectively I now have a free tablet! I remember zapping dead NiCads with a bank of electrolytics. I think it was metallic whiskers that caused an internal short.
Many thanks!
It may be the case with lose battery connector. Mine wouldn't even charge but I slapped two times on the back and it start charging.
Could be...However this was all tight connections. Its one of the first things I checked because I had had the tablet apart. But it was just below the voltage cut off. It still works to this day.
After a night on the pogopins, i got a nice 4.1 volts on the battery. because it fails to load on the usb conn, replaced the inner connector back to the original one. And..... its loading again on usb now. Perhaps the ribbon made bad connection. Learned a lot on the inner parts of my N7. All of this has nothing to do with your exellent video but will add information I wanted to share.
+Erik van Brakel Hey the important thing is you got it running again!!
My nexus 7 stopped powering on 5 years ago, I am finally able to use it again. Thank you!!!
my favourite tablet for years and its been in my cupboard for most....tried everything until i watched your video.......FIXED IT! You my friend are a legend and cant thank you enough. Its too old to do much with now so im going to use it as a controller for Tidal on my HiFi setup. thnaks again!
Glad it worked Steve! I couldnt believe it myself when I tried it. And I am also a fan of keeping older electronics, even if they are useless. I can play every SEGA Game Gear game on my Raspberry Pi....but I still have that Game Gear haha.
IT WORKS! Thanks man. I'm a simple mechanical man. but this was easy.
Nice!!! Glad the video is still helping folks!
Thanks, great video. I like your idea with the needles as I was about to spend more money on Alligator clips. Have not tried yet, but I hope your trick will work with my completely dead Nexus 7 (2012) that's been entirely drained and is completely unresponsive now.
How did you make out? Did you give it a try yet? Thanks for watching and commenting!
awesome. it worked. and you've explained and done it in so layman terms.
Glad it worked!!!
Thanks for the help. It worked very well.
It works. I connected a 2A charger and just had the cables in for a minute and when it started up i could stick in the usb cable to let it fully charge. Excellent little trick.
Glad it worked for you! Thanks for letting me know!
Just trying this now. Let’s see if it does anything
After you jump start it back to life. Expect to perform open heart surgery on it as well ...lol... The current OS makes them run terrible. I recommend installing an OS that supports 7.1 android (lineageOS) There are plenty of guides online to help you with that. Hope this helps someone!
Used a current-limited bench power supply set for a max of 3.7V and 100mA to jump-start the battery. Worked like a charm - it took a few hours at these settings to push the battery over the threshold. I think it had to reach 3.4V before the tablet would start. Now it reports 1% charged, but it's alive!
Awesome Martin! Glad you got it back working!
Thanks. My 2012 nexus which has been gathering dust for 3 years is now working again
I used a bench power supply set to 3.7v and 0.5A, charged for 5-10 mins, the battery is charged to 3.7v but still not booting up… with usb current meter the tablet is drawing 0.44A but still dead, any suggestions? Does the tablet have to be closed for it to work
@@darattaqwa Dude - these things are super old now! Just spend the $99 on an Amazon Fire tab and be done with it. Unless there's data on it you absolutely must have...
@@martinhobson8607 I was enquiring because I am learning how to repair tablets / phones / laptops
I have the 2013 model, but followed the same principles, and it's charged it like a dream. Now I just need to sort the USB connection so I don't have to pull it apart every time it needs another charge! Thanks!
Probably need a new connector. Those are likely online and cheap!
@@JEGsGarage well I went ahead and bought one, but I think I may have had a SNAFU! When taking the existing connector out, the connector to the silver cable that runs along the back of the battery broke. Do you know if *that* is repairable?;
Hey thanks a lot, it helped my nexus live again!!
CUDOS
Glad this trick is still working!! Thanks for the comment!
this shit actually worked. my 5 year old did it with me and she was really surprised that it brought the thing back to life. haha. seems like the memory on the tablet has either badly degraded or the battery has degraded because the performance of the thing is abysmal. I'm going to try to replace the battery and the charging port and see if that works. if not I guess it's $30 down the drain
It worked. Well that was unexpected 😀
OMG It worked for me to. I was going to junk the thing. now it booted up for the 1st time in like 3 years or more.
works thanks :) bought at a car boot for a £10 with 3 other tablets :) so very chuffed this has worked xxx
Nice! Sounds like you got a great deal! Glad I was able to help.
Man thanks a lot. It did the trick for me as well !
Thank you your a lifesaver i been trying to turn on my mom
14 years old nexus 7 tablet i gave up so many times
until i found your video i did what you did and it turn on
now it's charging normally again thank you so much
Can you fully charge the battery this way? My charging port is broken.
Not sure... Probably? But you have to watch because there is logic built into the charging circuits. They slow the charging down as you get close to 100%. I wouldnt just let this run wide open for very long.
Nice one mate just put 12v charger on for 20 mins and has now booted up back on normal charger now. In cubard for 3 years lol 👍
Man, i owe you a tablet! Thanks It worked perfectly
AWESOME! Thanks for the detailed explanation and solution that brought my Nexus back to life!!
+Charlie Ellison Great!! Glad it worked for you! Thanks for watching!
skip to AT LEAST 8:50 to see him actually start the repair. Talks too damn much.
Yup. You and maybe half a dozen others think I talk to much. Unfortunately, its the way I am. I dont plan on making videos that dont explain things and just hand out answers. The whole point is to understand why you are doing it...so maybe you can critically think yourself through the next similar problem. I appreciate the feedback either way!
Thanks! Mine was sitting around for about 5 years and the battery was very much dead, it had about 350 millivolts and just did the same thing you did, but I only left the 5 volts applied for probably like 5 minutes, I felt the battery it was getting warm, I checked the voltage after the 5 minutes after jumping, it was reading 3.75 volts, so I just put it back in and now it can take a charge and has revived this thing.
You've told about charging both the cells inner one and the outer one.But you had only charged the outer one practically??
+Malik Iqan Hi Malik. Right around the 12:00 mark I explain that inner/outer cell thing. Basically, the leads that go out to the battery connector are actually connected at the battery board. So there should be no need to charge each "cell". Just doing what I did should power the entire battery pack. At least in my experience it did.
+JEG's Garage till now i've failed in 3 times performing it but hope it works
JEG'S Garage: hi .. I switched of my tab for ~20 days and battery is almost dead, sign of even charging is also not showing up.mine one is 2013 model, out of warranty. I watched your vid and tried the same method twice but .. so, far no result yet. If you have any suggestions.?
+Ahad khan When you tried this method, did it show any signs of charge increase? Doing this only netted me like 5% or something. Just enough to get it turned on and get the charging circuit working again. Im not totally familiar with the 2013 model though...they're quite a bit different even though they seem pretty similar.
Not half as much as me, thought it was going to tossed so, thankyou!
Totally worked on my 2012 Nexus 7 that has been dead and unused for over a YEAR !!! My wall charger was getting pretty hot after only about 10 minutes, so I took it off and gave it a try. To my amazement the Nexus 7 started right up with a 30% charge already on it. So my only comment is that waiting a half hour may be a bit of overkill.
Awesome! It seems like some batteries take a charge faster than others. Mine was hooked up for longer than 10 minutes and it wasn't anywhere near 30%. Maybe it depends on how low the battery is, or how long its been sitting? Glad you were able to get it going though! Thanks for commenting and watching!
Yeah, its really work man...thank you so much
You're welcome!
Worked for me. I did a five minute jump start and it came on straight away. Thank you!
You've just earned a subscriber
Glad it worked for you! And thank you for the subscription! Hopefully I will have some more content coming soon!
yes..Yes...YES!!!!!!!!!!!!thank you !
Youre welcome! Glad the video helped!
1st attempt failed: I didn't have a wire stripper so I might have cut more of the silver wire then I should of. Bought a wire stripper and now have more wire to work with. Will try again today.
This method actually worked.
Just be extra careful while doing this method, afterall you´re hard charging a Li-Po battery.
Do it outside and be prepaired for a fatal failure of the battery.!!!!!
Im not sure you will have any issues with this, unless you really over charged it. The idea is to just give it enough juice to allow normal charging. If you left it on a long time, you could potentially cause a problem though. Im also not sure if this is a true Li-Po or if its something else. Good tip though, and obviously doing it outside, and not leaving it unattended for very long is a smart move! I pretty much baby sat mine for 15 minutes while I did other things. If it had burst into flames that would have been interesting..haha.
genius!
I just had to reconnect the battery it was loose, that was it.
thank you so much.
+Mrs cakori Awesome! Hey as long as the video lead you to the solution, whatever it was, Im glad it helped!! Thanks for watching!
This works! Thank you so much! Nexus 7, 1st Gen. Hasn’t seen light of day in 5 years.
it's not always the battery, it's also sometimes the bad mini USB connector. Gently push the connection up wait for 2 min, try to power, or down.. but really only gently so it does have connection
Once it's below a certain voltage it will not charge through the charge circuitry. My tablet had a good usb connector. Once jump started it charged perfect through the port. Still charges perfect to this day! I just don't let it sit unused without topping off the charge occasionally.
I had strange results but ultimately positive. I had jump-started the battery, threw it back in and nothing happened as I tried to turn it on the typical +3 second button press. So then I tried holding the power button down for 15-ish seconds as typically advised and it booted up.
Found it really strange so I thought it was worth mentioning.
I've had an old Nexus 7 chillin at the bottom of a bin of dead electronics that I've tried fixing several times...figured I'd give it one last go before recycling it and found this video -- and it's charging! Thank you so much.
mine's not working.
-i have no wire strippers
-i used needles instead of pins because i can't find any
-i have an asus me172v, literally the same battery as nexus
i tested it and i got 3.191 volts.should i try this?
my man thanks
If there isn't anything wrong with the tablet plug it in overnight before trying this. The charging circuit will work from zero but the tablet won't show anything until the voltage of the battery voltage reaches a sufficient level.
Hi Gary. I actually left it plugged in for several days. I verified the USB was good before this stretch. I could see the screen sort of, glow. But that was it. Never any charge indication, and the battery remained at an extremely low voltage. 1.xxx volts if I remember. I tried just about every non-intrusive trick I could think of to get it to fire back up with no luck.
my battery plug is not loose at all...in fact it feels like its GLUED on....so im outta luck. ;-(
Thank you! Your video was one of several I watched to get the Nexus 7 going again. Just want to let you know that this is still relevant. Mine had not been used since 2015 and this technique brought the battery back enough to get the tablet to reset and login, as well as getting a charge to "take" on the battery. The straight pin "trick" was awesome!
Hii there after another 30min jump start BATTERY showed me 3.91 VOLTS , but device doesn't turn on bro
I had a feeling that when I attached the metal parts I used for push pins it probably messed up the contacts
When I delved into mine, the battery wires are parallelled at the motherboard socket too, if this helps.
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My Nexus 7 stopped working/charging several months ago apparently dead. I assumed that it was broken having been in use for a number of years. Later I finished up buying a replacement. I was browsing TH-cam electronics and it crossed my mind maybe the Nexus 7 screen or other parts could be recycled, I Googled Nexus7 and a list of people commenting on having dead/unchargable tablets surprised me, and I came across your video. Following the procedure apart from leaving the battery on a 5V charge for about an hour, like you I didn't really believe it would work. After reassembly and switching on ***it booted up***, no problem. A load of updates to install and full recharge was all there was left to do. So I'm totally amazed and really pleased and sorry I didn't find your video earlier. Thank you very much from a grateful TH-cam browser.
+Michael Davies Thats great Michael!! Im glad the video helped you. Thats exactly why I take the time to do it! It makes me wonder how many tablets wind up in the bin because of this problem. It stinks that the fix involves some trickery, but Im glad to hear plenty of folks having luck. Thanks for watching and thanks for the great comment!
Hii just now brought brand new multimeter and tested BATTERY VOLTAGE it showed 3.75 volt
This works, but it's not the final solution for me. In my case, I am still not able to charge my tablet after I apply this video's solution. But this solution proves following:
1. The battery is not charged from micro USB for some reason (I think the USB port is damaged).
2. The battery is in good condition and can be charged directly like this video shows, although USB output is 5V+ that is higher than factory suggested battery charging input.
After watching other videos, I find that there is another port on one of the long sides can be used to charge this tablet. It's four metal dots and designed to work with charging dock originally.
I made an adapter to connect this charging ports by cooked USB cable and finally it resolved my problem. My adaptor is too ugly to show, the basic idea is to use the micro USB cable you cooked by following this video to connect the metal dots on the side.
One more thought,
It looks like there is a electronic gate between USB port and the battery. If the the battery is too low, the gate can not be opened. If the gate is not open, the battery won't charge from USB and will be lower. This is a logic deadlock bug by design. The jump start solution breaks this deadlock. So that's why it works.
+Lawrence Zhou Hi Lawrence. Yup...thats exactly what I think is happening.
As for your above comment. If your device is powered up, and it wont accept a charge from the USB cable, 99% of the time your USB connector is bad. Its very common with these tablets. You can pick up a new USB board fairly cheap...at least you used to be able to.
As for the side pins, that is usually how people determine the USB connector is bad. Because the tablet will charge from them. I dont think the tablet will accept a charge from the side pins if the battery is flat like mine was. I cant say for sure, because I didnt try it. I tested to see if there was a link between the positive and negative side pin, and the positive and negative of the USB. I believe the grounds were common. But the positives were not. So they must be going through a different circuit or gate at some point. Be interesting to try to charge one through the side pins if the battery was too flat to charge otherwise. Thanks for the comments!
Worked for my Nexus 2012.. have had it laying around for like 2 years.. because i thought it was totally broken. Did this, and it's alive again!
+Herman Willems Awesome! Glad it helped!
Ok i hope my nexus 7 2013 likes this i see the 2012 does D:
Disadvantage: Every time the battery runs out.. i got this problem. :( I need to keep it charged!
+Bodacious T Let me know if it works on your 2013. I dont see much reason why it wouldnt!!
Herman Willems Are you letting the battery drain until the tablet shuts down? I would think it would still charge at that point. This issue usually only crops up if you leave it with a dead battery for days or longer. It slowly drains past the normal working voltage for the charge circuit. If every time your tablet battery dies, you cant just charge it right away, then something else might be wrong with the battery/circuit.
Was just about ready to toss my Nexus 7 because it wouldn't boot up or apparently charge. Tried your solution last night and, Voila!, I have a usable tablet again. I didn't bother to remove the battery from the device when I kick-started it though, just unplugged it from the unit. Thanks for sharing.
+Chris McLain Hi Chris. Glad it worked!! I wonder how many Nexus 7's, or other devices, wind up in the landfill because of this problem? Good point on not removing the battery. I thought I mentioned it, but I only did that to be able to show what I was doing better. Also...being a LiPo, I didnt want to risk it doing something odd and destroying the tablet haha. I wouldnt hesitate to leave it installed now though. Thanks for watching and commenting!
Thank you but doesn't work unfortunately I be the one fooled by "GOOGLE ASUS "
okay got a charge finally with this method won't turn off bought an asus charger not taking a charge please help
+Jackie Fernandez It wont turn off??? Thats strange. So it was dead, you jump started the battery, it fired up, now wont turn off? Did you remove the battery completely while doing the jump?
MEN WTF ... THATS REALLY WORK !! ❤❤❤❤❤❤❤❤❤❤❤❤❤ THX !! VERY MUCH !!
You the Man.. my tablet decided do same suddenly to just grind my last nerve till fixed & ready to toss it. tks for sharing your know how it really detailed & concise but need HELp my tablet has 2 batteries, is that possible& if so so i have charge both the same the first?
Molly B two batteries? What kind of tablet? Never saw that before. But if you want to try it, first I would verify that each battery is a 5 volt battery. If they are, do one or both at the same time. If for some reason they are like 2.5 volts you would have to do something different. I doubt this is the case, but want to warn you to check the output of the battery before hooking it to the USB cable.
My battery has been dead for over 2 years... Let's see if this trick works on a battery that's been dead for that long
Please let us know how it works out! I havent tried to bring one back from that long!
OMG 😱 it worked !!!!!!
Cheers buddy, this worked a treat...however it's shed light on what looks like a faulty USB connector (no juice flows when connected), looks like I'm replacing that next, but your video helped get some life into that battery where everything was failing...much appreciated!
Thanks for the comment Fran! Glad the video helped! Those USB connector boards go bad pretty frequently. They are fragile and finicky.
I know nothing at electronics but i was desperate to get a charge as all other methods failed. This worked a treat was even more surprised than you were before turning the devise on. I recommend this method if you can't turn on your tablet through other on/off methods. Thanks for the good video and walk through.
+Sean Mc Kevitt Glad it worked for you!! I still cant believe it worked haha. I want to dig up all my electronics that I hoard that dont turn on anymore and try this. Thanks for watching!
Got a refurbished Nexus 7 (2012) tablet from Walmart. Battery was DOA and tablet would not start. This did the trick... Thanks.
KCW Awesome! Glad that it worked! Bummer that your battery was DOA when it was a new unit. Thanks for watching!
this is awesome, i also used sewing needles and an HP Touchpad charger. Sacrificed a USB cable and 30 mins later it's booting! now what the hell do I do with a 4.5 year old Nexus 7 :-P
That is the question Tim! They make decent in car navigation/entertainment. While a bit slower than the newer tablets, they'll still run basic tasks really well. Or use it when you wouldnt normally use something nicer haha. Like with greasy hands or by the pool or something. Glad you got it working either way. Worst comes to worst you could wipe it out and sell it online for a few bucks!
I jumped started the battery it turned on I bought a true charger and it does not turn off or take a charge aNt suggestions
+stephanie cordero Someone else mentioned that. Not sure what that is about. Ive used this method 3 times now, and lots of people have had it work for them. Did you try holding the power button for an obscene amount of time? Like 30 seconds or so? Maybe try to disconnect the battery, reconnect, and fire it up and see whats up? Also...not charging through the USB once you have it working could be a sign you have a bad USB port.
Thanks for your helpful video. I had ordered a new battery for my Nexus 7 because it wouldn't come on. And it wouldn't charge. I let my Nexus 7 set for two months and finally for Christmas got a new iPad mini. I love it but I decided to look for a video to see if I could fix my Nexus 7. I thought it was impossible to fix. I followed your video and now my Nexus has booted up and is charging. I am so pleased. I learned a real lesson, go to TH-cam first when I have a problem.
+Charles Lawyer Awesome! Glad it helped bring your Nexus 7 back to life! Keep the Nexus and do a car install now that you have an iPad :)
Hi All this is how I "jump started" my Nexus 7 I check the battery connector first, that was fine. Then I connected the Nexus to the charger for 30 seconds, disconnected for 30 seconds, connected for 30 seconds, disconnected for 30 seconds... etc. Until I got the battery charging image. Give it a try. Thanks for this video!
+JumpingMOUSE! That is one of the 'tricks' reported to work for these. I must have tried that 60 times in a row while bored one night, and the only thing I felt like it did was wear out my USB port faster haha. I think this works depending how far depleted the battery is. Im thinking it takes a tiny bit of charge before it detects the low voltage and shuts the works down. If it takes a tiny bit of charge, a dozen times, it might pull it up enough to trigger the charge circuit. Maybe if I had done it 100, or 500 times, it might have worked? Its certainly worth a try before diving in deeper though! Thanks for the comment.
+JEG's Garage Yeah... I just unplugged the usb cable from the adapter so I would not wear out the port! On another note, I am running 5.1.1 on this first Gen Nexus, I think Google will not update it any further. I have noticed it becoming fairly slow after the updates and have tried resetting to factory settings and clearing the system cache. Do you have any recommendations for 1st gen nexus 7's... I have seen some hacks online to get it up to 6.0 but I am not sure if this will make the system any faster or be secure. Thoughts?
+JumpingMOUSE! Duh...unplug from the wall wart side! Haha...didnt think of that. I guess I was too lazy to reach? Good call haha. I dont know much about upgrading past 4.1.1 or whatever it is. Im running Timur USB rom, and that wont support any higher Android than what I have. I have thought about trying a different kernal. But this one works so darn well, and the tablet is pretty snappy unless you're running Bluetooth with WiFi and GPS all going at once. CPU maxes out fast. Otherwise, it still runs way smoother and faster than the Pioneer AVIC headunit that it replaced, with a 10x better screen, 100x better functionality. If I ever move away from the Nexus 7, I will probably venture into the more current Android versions and see whats there. Sorry I have no advice for you on that! XDA forum would probably be your best bet.
I tried your method twice. Now the screen has a flicker of light. I replaced the battery and got a new charger. Any thoughts what else i might be able to do. Thanks.
Jackie Fernandez So you got a new battery and it still wont turn on? Sounds like there's a hardware issue somewhere...assuming the new battery is charged and good. Did you try this trick on the new battery for a little while? Sometimes even new, unused batteries can flat line from sitting. There is a guy below that got a brand new one and it was dead/wouldnt take a charge. If everything else checks, then the tablet might just be dead.
'll well and good but my non tablet powers up but will not open by the normal swiping as usual.
That was ONN tablet from walmart
Thanks, worked for me!!!
+vijshedbal Awesome!
Worked perfectly
Great!!
Hey Jeg, just tried this on my tablet and it brought it back to life!!! after only 10 minutes!!! It will not charge though. I tried a charger that I know works with my cellphone and it does not show any charging activity. Looks like it might need a charging port. Thanks so much for sharing this video!
Hi Maria! Glad it brought the tablet back! Sounds like your USB port is bad like you said. Pretty common. You can usually pick them up pretty cheap. Depending on the tablet you own, it shouldnt be too hard to replace either. Does your tablet have side connectors that you could charge with a dock?
Man, first try this: I just unpluged the battery from the mobo, and than pluged it back a minute later, and it started to charge...
Yup...tried this. If the battery is too flat, this wont do it. Sometimes batteries will sort of "self recover" if you turn off the item, or remove the batteries. Im not sure Li-Po tech does that the same way as other batteries. I literally tried everything, and was about to buy a new battery or ditch the tablet. Nothing worked...except this :)
tapping it gently ,in 4 places worked for me, thks, Vaishnavi
Thanks man! You save me!
Glad it worked Giuseppe!
Tried this, it worked perfectly, thank you!
Glad it worked for you Ruth!
Really didn't think this was going to work but I'm very grateful to say it did and the Nexus 7 is back up and running! Thanks a mill...
No problem! Glad it helped you out. One more Nexus 7 saved from the trash :)
These Nexus 7s are junk! Ive had 2 and both have had power issues.
Seems hit or miss with them. Ive been using one as an in-dash tablet permanently mounted for years now. Battery still only drops a couple of % over night, and charges up fine.
Thanks a million. It worked like a charm
+Ricardo Gomez Awesome! Thanks for letting me know! Glad it helped.