Database Users

No LED indicator lights on 8525

Hello again, I finally bought the 8525 (As-Is for $115) on Tuesday from an eBay member, which arrived Friday. There was a known issue with the phone not turning on, but I just figured it was a battery or maybe a bad power supply. The following day, I purchased a 3-piece AC/DC/USB kit for $6.29, which arrived Saturday. Just last night I ordered 2 Li-Ion batteries on eBay for $12.98. I also downloaded the pdf of the owner's manual for the 8525.
With the above scenario in mind, I do not see any indicator lights at all when the USB cord is plugged into the phone and computer. I've read that "jump starting" the battery may help it charge up again, but is the solution that easy? I may have misinterpreted that as meaning to use the jump start if the LED is red only -- not when the LED out completely. If that idea fails, would using a new battery be a quick fix?
I am being very cautious with my investment, so bear with me. Once the phone powers on, which version of the ROM should I install? I don't want the phone to crash or, worse yet, never work again. What about tweaks (programs) to add to it? I've seen a few listed on various threads, but not really noticed if they work independently (i.e. not in a series with other programs, but 'a la carte').
Thanks in advance for your patience and future help with a novice phone tweaker. If possible, use "layman's terms" as I've never tweaked a newer phone and I'm not really up on the lingo.

Just a quick update . . . I attempted to power up the phone via USB cable, with the battery removed, and still no red LED appears. The phone doesn't show the "white dot" having changed colors, and the battery still has the normal red polka dot on white background.
I know that's not much info to go on, but any ideas what could be wrong? I have never seen the phone powered up, nor has the person I bought it from had it powered up. However, the person he received it from did say it powered up for her.
Thanks for any assistance!

If tyhe red led doesn't turn on when you connect into the power WITHOUT the battery then theres something wrong with the hardware... It should show the red led when connected to the power, Orange for charging and finally Green for fully charged.
You may have bought a dud, sorry...

Yep, does not seem hopeful. As stated above the Red LED should light when plugged into charger if the battery is out or if the battery is not charging, otherwise it should be orange to show it's charging.
It might just be a disconnected internal connector but I'm doubting that a little. It may be the internal fuse:
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But replacing that or even testing it is not an amateur job unless you have a good knowledge of electronics.
Mike

mikechannon said:
Yep, does not seem hopeful. As stated above the Red LED should light when plugged into charger if the battery is out or if the battery is not charging, otherwise it should be orange to show it's charging.
It might just be a disconnected internal connector but I'm doubting that a little. It may be the internal fuse:
But replacing that or even testing it is not an amateur job unless you have a good knowledge of electronics.
Mike
Click to expand...
Click to collapse
Sorry for the long delay in replying, I've been away from the computer for a while.
Yesterday, I did take the 8525 to a "Sprint/Nextel/Verizon" seller/repairer.
He couldn't fully repair it, as AT&T didn't give him permission to do so. He did assist me as much as he could. He thought the charging port may have been loose, so he checked it and reseated it . . . but that didn't help. I also mentioned to him about the fuse [as I read that was a problem on another thread] but he didn't see it as blown.
I found a website online that says they can repair any cell phone issue -- even water damage -- starting at $29 (parts are sold separately). I am considering this, if it is plausible to be repaired at all. I would like to do this option as a last resort though. Are there any other options to look into beside the fuse or charging port?

Before giving the go ahead, find out how much are the parts and if they are being re-used...
Cheers...

ultramag69 said:
Before giving the go ahead, find out how much are the parts and if they are being re-used...
Cheers...
Click to expand...
Click to collapse
Great idea, thanks! I would need to know what other parts could need replaced, so to ask their pricing. There was another repair place in New York state that repairs for $99 or so. I doubt either of you have used their services, but in general what would be the cause of such difference in pricing? Is it the same in the cell phone world, "What little you pay equals the same amount in quality."? Does anyone from the board here who's used that company's services have any feedback from them?
On a tangent, I have read that the "white screen of death" may not be fully repairable, so I hope my phone doesn't have that issue when it's fixed! (I Just read the first and last page of that thread, as most of it was over my novice head.)

I have a 8125 and a 8525. I had a problem when trying to charge them when completely dead. After talking to ATT I found out that once the phone goes below a certain charge, the charger I bought and the usb charger did not have enough miliamps to charge the phone. I could not get any LED's to appear. I had to buy the manufacture recommended charger. Once I did that the phone charged with no problems and the LED lights appeared as soon as I plug it in.
Get the specs on your charger and make sure your charger has at least the recommend milliamps for charging or buy the manufactured charger. I made sure at that point not to let the phone go completely dead so I could use other usb and cig chargers on the go.

gblacknall said:
I have a 8125 and a 8525. I had a problem when trying to charge them when completely dead. After talking to ATT I found out that once the phone goes below a certain charge, the charger I bought and the usb charger did not have enough miliamps to charge the phone. I could not get any LED's to appear. I had to buy the manufacture recommended charger. Once I did that the phone charged with no problems and the LED lights appeared as soon as I plug it in.
Get the specs on your charger and make sure your charger has at least the recommend milliamps for charging or buy the manufactured charger. I made sure at that point not to let the phone go completely dead so I could use other usb and cig chargers on the go.
Click to expand...
Click to collapse
Thanks for the response! I feel honored that I was your first post on this site, that is very thoughtful of you to register just to reply to my problems!
I don't have the AC charger that came with the cell, but I did buy one on eBay -- not sure if it's the same specs as the OEM though.
I just got back from an AT&T repair/replace shop. They couldn't repair the phone, so they gave me a reconditioned one in place of it! I'll post another thread for other help with the phone. Mostly tweaks and software "upgrades" (if you get the drift).
Thanks again to all who replied to me! I greatly appreciate all your time and efforts!

The charger should be 5v 1A. If not, then it's not the right charger.

CRCinAU said:
The charger should be 5v 1A. If not, then it's not the right charger.
Click to expand...
Click to collapse
That's correct. Many chargers for various other phones etc are 5v 500mA and although they will work they can cause problems through being underpowered. Strange things can happen like the phone not charging unless it is turned off, sudden battery drain despite being plugged in and in some cases the battery charge can drop so low that the charging circuit gets - how shall I put it - confused.
So an underpowered charger is OK for occassional use but I would personally only use it with the device either off or in standby mode to top up the battery. I would NOT use it if my battery was below 10% charge and I would not operate the device whilst plugged into a charger with less than 1A.
Mike

Completely Dead, No LED
I read this constantly but don't post often. My 8525 from ATT is out of warranty and did this same thing. It went dead while I was at a football (American Football) game. When on wall charger there's no Red LED. Seems like the fuse or some other major hardware meltdown. I have 2 batteries and put both in a friend's 8525 and they work perfectly. I cleaned battery connectors in phone.
Any suggestions on identifying the problem or fixing it? I'm waiting on the ATT Fuze to replace this and am now stuck on an old RAZR.
Any help would be greatly appreciated.

cparkhorn said:
I read this constantly but don't post often. My 8525 from ATT is out of warranty and did this same thing. It went dead while I was at a football (American Football) game. When on wall charger there's no Red LED. Seems like the fuse or some other major hardware meltdown. I have 2 batteries and put both in a friend's 8525 and they work perfectly. I cleaned battery connectors in phone.
Any suggestions on identifying the problem or fixing it? I'm waiting on the ATT Fuze to replace this and am now stuck on an old RAZR.
Any help would be greatly appreciated.
Click to expand...
Click to collapse
You've proof it's not the battery
Without testing it's impossible to be conclusive but likely culprits are the m/board fuse (as you say) or the soldered battery connector contacts (to m/board). One other more remote possibility might be the main internal flex cable connector - less likely I think but it would cut off the led daughter board if it was not connected along with everything else. (Less likely as it is held in place by tape.
Mike

Can fuse be replaced
Thank you Mike. Can the fuse be replaced or does the whole motherboard need to if that goes?

cparkhorn said:
Thank you Mike. Can the fuse be replaced or does the whole motherboard need to if that goes?
Click to expand...
Click to collapse
It could be replaced if you can locate the correct component but not something to do with a standard soldering iron. A repair centre should manage it.
Mike

Though would probably be cheaper to find a "broken" Hermes and use for parts than send to repair center...
Cheers...

totally dead wizard after battery drain

Hi,
That's the first time I am not able to find in this great forum a solution for a problem with one of my 2 wizards (i love this machine...)
Yesterday, one suddenly did not power on. I knew that the battery was pretty low, so I guessed was just discharged. But once I plugged it at home to the wall charger, no amber light appeared, nothing powered on! When I replaced the battery with a fresh one, nothing changed... and when I tried the "bad" battery with my second wizard+wall charger, I confirmed the battery was almost empty (2%), but worked fine.
I tried to plug the mobile to the computer, but nothing... to soft-, hard-resets... the bootloader reset... but my wizard did not respond electrically or electronically to anything... any idea what could be happening? any possible solution? I do not remember exactly which rom I was wearing now, if that matters... probably a FariaWM6_realthing_crossbow
thanks to all in any case
marcos

Maybe out of sight accident
why you leave alone your lovely wizard and so aprecciated mmmm....
its xtrange but as you say i think this kind of forum may helps you with software... took it to a cellphone repair center... they has multimeters to know where does the energy stops... maybe a little electronic component has burn it down. or try the not original and official wall chargers withj specific mhz and amperage, try something more hard.
hope i help you

more news
After being overnight without the battery, this morning I tried a "resurrection"
I just put back the battery, did a softreset, and it worked!... really!? no... just the first two screens (HTC welcome and machine tests) It did not go forward, and a second reset it did not work either... now it's again like yesterday, just dead
I think there is something else than just an electronic problem, but who knows. I recommend you not to let the battery too low!
Marcos

Charging a completely dead Wizard battery
Delapena,
I've had this problem a bunch of times with my Wizard (Cingular 8125 branded version). I was able to get it working again using the instructions of a VERY helpful person(s) who I want to give credit to but cant remember right now (sorry in advance) so just FYI this works for me, but the credit goes to the original poster (will edit later if I recall).
Easiest method (if available):
1) Locate your STOCK 5vdc/1.0A wall charger.
2) Remove stock battery, put it in a ziplock bag, place in freezer for 5-10 min or so. This should minimize the internal resistance of the battery to boost VDC across the terminals (in case you ran the battery very, very very dead).
3) After the battery is good and cold, put it back in the phone; DO NOT PRESS THE POWER BUTTON!
4) Plug the 5vdc/1.0AMP STOCK WALL CHARGER into the phone.
5) Charging indicator (solid amber LED) should light up after 5-10 seconds with no other indications (no screen, no beeps, just solid amber LED ON).
It's my understanding (may be wrong) that the 1.0amp wall charger uses/supplies 5vdc one one or more of the mini-usb plug pins than the standard USB->mini-usb cable used for standard data-transfer on standard USB-spec devices. Also, the wall charger sources a full AMP of current at 5vdc, as opposed to the 0.5amp each USB host IC is allowed to source (e.g. the USB host IC on your motherboard/front/back of computerbox).
...reply to this if you want the comprehensive method. Ill research if above doesnt work / you dont have the charger. Swamped at present though; if you need the full blown recharge-the-battery-from-the-stoneage method ill look it up---dont want to give you invalid info.
If you dont want to wait (i'd understand, been there), try searching around a bit if you havent already found what your looking for.
Reply back if you need more help, otherwise, good luck and replace your battery with a new one asap!
Cheers
(again, no credit to me on this one, got this solution from somewhere else on the forum a long while back...credit to original poster!!)

Sir,
I didnt read what you had already tried. My wizard is rebooting constantly as well. My thought is that my battery is so old that the battery charging chemistry is so out of whack that the battery charging / voltage sensing circuit is all sorts of confused as to where the (really old worn out) battery is on its charging curve.
I'm guessing that my phone is rebooting because the battery fails to supply adequate voltage at x.xx amps of current draw to the phone's internal voltage regulator. When the IVR cuts out, the phone poops its pants.
I'm currently looking for a battery replacement myself.

more... but less
Thanks for the help, brhestir. But did not work for me. Actually, I tried with the 3 batteries I have, which actually work OK in my second wizard.
The only thing I am able to "slighlty" reproduce till now:
1) Wizard remains several hours with any battery plugged
2) I put the battery back
3) I switch it on or do any kind of reset
4) Just sometimes, the machine starts up, but gets hanged up after the first screens
5) most of the times, after this... the screen turns white slowwwwly, till it switches off
6) only once, I managed to get the bootloader screen, which stayed like that with any problems... but the computer cannot connect to it, so impossible to change the rom.
Next step: to dismantle the machine (prior step before throwing it through the window)
Marcos
brhestir said:
Delapena,
I've had this problem a bunch of times with my Wizard (Cingular 8125 branded version). I was able to get it working again using the instructions of a VERY helpful person(s) who I want to give credit to but cant remember right now (sorry in advance) so just FYI this works for me, but the credit goes to the original poster (will edit later if I recall).
Easiest method (if available):
1) Locate your STOCK 5vdc/1.0A wall charger.
2) Remove stock battery, put it in a ziplock bag, place in freezer for 5-10 min or so. This should minimize the internal resistance of the battery to boost VDC across the terminals (in case you ran the battery very, very very dead).
3) After the battery is good and cold, put it back in the phone; DO NOT PRESS THE POWER BUTTON!
4) Plug the 5vdc/1.0AMP STOCK WALL CHARGER into the phone.
5) Charging indicator (solid amber LED) should light up after 5-10 seconds with no other indications (no screen, no beeps, just solid amber LED ON).
It's my understanding (may be wrong) that the 1.0amp wall charger uses/supplies 5vdc one one or more of the mini-usb plug pins than the standard USB->mini-usb cable used for standard data-transfer on standard USB-spec devices. Also, the wall charger sources a full AMP of current at 5vdc, as opposed to the 0.5amp each USB host IC is allowed to source (e.g. the USB host IC on your motherboard/front/back of computerbox).
...reply to this if you want the comprehensive method. Ill research if above doesnt work / you dont have the charger. Swamped at present though; if you need the full blown recharge-the-battery-from-the-stoneage method ill look it up---dont want to give you invalid info.
If you dont want to wait (i'd understand, been there), try searching around a bit if you havent already found what your looking for.
Reply back if you need more help, otherwise, good luck and replace your battery with a new one asap!
Cheers
(again, no credit to me on this one, got this solution from somewhere else on the forum a long while back...credit to original poster!!)
Click to expand...
Click to collapse

wow i just ran into the same problem today.. my battery was low tried to plug into the cigar lighter but the fuse was blown due to another object i had plugged in so i didn't get a chance to charge it, the phone was fine all day until i left work it was completely dead.. no amber light for the charger.. have you had any luck?

hi everyone,
i solved this problem by creating a sort of bypass for the battery...
i bought a special battery used for some circuits experiments which is 4,5v..
i connected the + and - with the phone contacts, with the battery plugged...turn on the phone until the orange light is on and leave it until charge is full...
this is cause phone needs a minimum of charge to start recharge circuit...

Yes the same problem on every post
The thing of cooling batteries is an old but knowledge charging fast option but it brokes your performance batt drain so i recomend a new full battery ok? is the only way or...... charge the one you have fully fully.
and try again! tu plugin the batt once at time and again and again it wouldnt boot cause its too low to begin the OS and let you charge with the wallcharger... to charge with the wall or usb you need a bootable and functional OS ok?
hope you can find a way to charge your batt at least sufficient to boot the OS ok?
bye

well good news! 20 minutes in the freezer + 5v + 1a = win

CONGRATS!!!!!!!!!!!!!!!!!!!!!
mp86 said:
well good news! 20 minutes in the freezer + 5v + 1a = win
Click to expand...
Click to collapse
So dont ever let the batt drains to the hell down forever hahaha.

+ Que PPC said:
So dont ever let the batt drains to the hell down forever hahaha.
Click to expand...
Click to collapse
lol it was an accident i thought it was charging in the car!

Dead Battery HTC Wizard

Hi all, for those of you that have experienced a totally dead battery you'll know the pain it is to get it going again. I have recently had this happen and decided to post a fix on here.
Lesson #1 Dont let your battery die completely, if you get a low battery alarm, turn your phone right off till you can charge it.
Lesson #2 If your battery dies completely, just throwing it on the charger wont charge it. This is because the Operating System looks after the charging. If your OS wont load, your battery wont charge.
FIX:
After trying various methods on the net, I found a surefire way to jump start your Wizard so you can get it charging.
You'll need : 3 x AAA batteries and 2 lengths of wire and some tape.
I cheated here, I managed to pull a 3 pack AAA battery setup out of a regular Panasonic cordless phone which saved me having to piggy back the batteries.
1) If you dont have a battery pack, you'll need to piggy back the batteries. + to minus on each one so that you have 3 batteries connected to each other with one free + and - side. Use the tape to keep the wires from moving around and getting loose.
2) Remove the battery from the phone.
3) Put a wire from the + side to the top connector of the phone battery connection ( top gold pin, right hand side of phone nearest to the power button )
4) Put the other wire from the - side to the bottom connector of the phone battery connection ( bottom gold pin, right hand side of phone nearest to the camera button )
*** There are 6 gold connections sticking out on the side. Make sure the wires only touch the top and bottom pins. Bend them round if you have to and clip them if needed.
5) Try the phone and it should switch on now. If it does, push the battery back into place while its loading.
6) As soon as you get to the today screen, plug your charger in. Wait about 1 minute and check its charging ( from the battery icon under seconds ).
7) If its charging remove the wires from the AAA battery combo ( in case they explode or something ).
Hope this helps the next poor soul that didnt have time to charge their battery before it died completely. And thanks to all the posters that have helped me out with my problems. Long live the Wizard

While this is a good post, it in not entirely true. If your battery completly dies, you can infact use a standard wall charger that outputs 1AMP or more of power to charge it with, even if you phone wont start. The charger that is included with all HTC devices outputs 1AMP, so they should all be useable. Good post otherwise though!

Thanks ashasaur. When I posted this I did not have access to a standard wall charger. However looking at getting one just in case this happens to me again. HA I hope not.

Thanks for all that advice. In desperation, I have just bought a new battery and was relieved to see my Prophet come back to life, having, yes, let the battery run completely down. (I am away from home, where I left my charger as the Prophet seemed to charge quite happily from a USB port)
If 3 AAA batteries work ok (~4.5 volts), wouldn't it be a bit safer just to connect them to the dead battery for a while, as described above, to give it a bit of a charge, rather than risk the phone, or isn't 4.5 volts enough? Greg

buy a 4.5v 500ma adaptor and it will work
Earlier I was afraid of dead battery and use to turn off my kjam but later I got an idea and purchased one 4.5 v 500 ma wall adaptor($1 only) and cut the end socket and use it to give initial charge.
Earlier I was so much worried about my battery that had to put it in charging point where ever I find a usb port but now seems Kjam battery knows that's why haven't died for 2-3 months even though sometimes I forgot to charge it in night

pawanmehta said:
... purchased one 4.5 v 500 ma wall adaptor($1 only) and cut the end socket and use it to give initial charge
Click to expand...
Click to collapse
Great idea. Just tried it with an in-car USB power adaptor, but it didn't supply enough oomph. If you follow pawanmehta's advice, you might want to check out this site - USB pin out and lead details - for the correct leads to wire up.
A quick look around the internet suggests that mains to USB power adaptors are available at £4.85 (UK) or $15 USA but I expect a proper search would turn up cheaper items. Greg

It works with a O2 XDA Mini S, but it didnt work at first time: I have to put the cable with the 3-battery-arrangement and the 3.7 1400mAh battery at the same time, it's looks like that it wont turn on if the pins are not pressed, but well, I succesfully boot and now i'm charging (i remove the 3 battery arrangement).
And, I use 3 AA Duracell batteries, I tought it's the same than using 3 AAA, 'cause they use the same voltage (1.5 for common, and 1.2 for rechargeable).
Best regards, and thanks a lot MattyZee, u have my blessings

It works with a O2 XDA Mini S, but it didnt work at first time: I have to put the cable with the 3-battery-arrangement and the 3.7 1400mAh battery at the same time, it's looks like that it wont turn on if the pins are not pressed, but well, I succesfully boot and now i'm charging (i remove the 3 battery arrangement).
And, I use 3 AA Duracell batteries, I tought it's the same than using 3 AAA, 'cause they use the same voltage (1.5 for common, and 1.2 for rechargeable).
Best regards, and thanks a lot MattyZee, u have my blessings

hey everybody...
i read the thread a few days ago and thought...okay good to know but that will never happen to me now that i know that it shouldnt...
now...a few days later...of course it happenend...
soo...i tried everything. but the things are complecated to do alone...with all the wires and then pushing the power button and installing the battery again...
so i had to give up...
but here is another way how to do it...
it is already beein mentioned i think...
use the 3 battery combo, 2 wires at both ends, take out the dead battery and put the - wire to the pin at the very botton (the bin at the longer end) and the + at the other end.
hold that just for about a minute (i think i just holded it for 10 seconds but a minute would be better maybe...)
and then put the battery back in and it should start...
oh and i tried to use a 1400mA wall adapter and it didnt worked...
but try to avoid that...
it is not a nice situation seeing youre wizard dieing like that...
and at first i thought it is not the battery...i thought it is broken...
so avoid it if possible...
thats it...

What is length wire (sorry if it's a idiotic question)
please help
btw, I have O2 xda mini S.
And can I use 3 AA batteries????

thanks a lot,it worked
once again THANK YOU

You guys are geniusses It started, but when it started I put the charger in it fro my laptop and waited a while (removed batteries) then i saw it was charging but when I was waiting some more it yust fell off !! So i started it up again with the AAA's and then putted charger back in and i was using the phone, I saw it was charging and I looked @ lvl and it kept on saying it was on 0 % :s Then i thought let me wait a while and i stopped using it so it fell off again, what did I do wrong twice ?
Thx

A 9v Battery (The type you find in smoke alarms) does the job as well.
ONLY connect it for a couple of seconds, but repeat about 5 times then connect it upto a usb data lead and after about 10 seconds it should kick in.
After its been charging for about 30 mins turn the Wizard on.
Have succesfully used this method on 3 Wizards now and it works every time!
Don't Forget To Put The Battery Back In Your Smoke Alarm!

Exceptional
Thank you. I have a Kaiser that I love, and was just handed a Wizard that wouldn't even start. This post let me boot it and start the charge.
Thanks.

Apologies for bumping an old(ish) thread but I've tried this jump start method and seem to be having no luck with it.
I've tried the methods suggested, using 3 AAA batteries didn't seem to do a thing for me, but I've had a slight result using one of those square 9V batteries; the camera flash comes on and the screen lights up but wm doesn't begin booting up (the screen just stays blank but lit).
I've also tried attempting to give the battery some charge using the method mentioned earlier but that too doesn't seem to be working either.
The battery in question is brand new (one of those extended ones with a higher mAh) and I'm assuming it's arrived with zero charge in it.
Does anyone have any suggestions?
(incase anybody is wondering, the wizard boots up fine using a different battery which is charged)
edit: if it's of any relevance, the wizard's a g4.
edit2: I've tried charging it with the wall charger but all that seems to happen is a red light flashes once every 5/10 seconds and the screen flickers on then off

Update: After numerous attempts at jump starting, my wizard now refuses to charge whatsoever.
The light flashes orange (I did follow the guide posted on the wiki about that but it had no effect) but it comes up saying it's charging onscreen, however it simply doesn't charge (the battery life just slowly drops).
It's the same using either the wall charger or usb.
I did try taking the battery out/doing a soft reset/doing a hard rest but to no avail.
Would I be correct in assuming my wizard's now broken?
I'd just donated my blueangel to a friend too as I thought I'd no longer need it, but now i'm left without a phone

I've found a standalone battery charger on the internet for around £10 or so, I might give that a try. If it works, I'll have my wizard back, albeit without being able to charge it while it's switched on. On the plus side, it would eliminate the need to jump start it ever again though.

wizard resurrection...
This problem is quite a hard time for the wizard users...
I know many users with 2 or 3 wizards in the closet because they just died, and there are none powered batterys around...
I hope this can help someone, somehow...
WIZARD RESURRECTION
Props to all!
undertuga

How did u make out with the battery issue? I have the same prob and the light on the camera lights up but i can't get it to charge and i'm using a new battery any suggestions would be helpful. Thanks

Just to repeat a comment made by ashasaur 12 months ago. You need a 1amp charger. Although someone had success with a 500mA charger, that wouldn't work for me, whilst a 1000mA (1Amp) charger worked to recover a completely discharged battery.
A new battery should not have zero charge. NiMH batteries do not like being left around fully discharged and, to the best of my knowledge, are not supplied discharged.

[Q] Battery Charging - Current Draw When Complete

Guys, I'm hoping someone familiar with LiPo battery charging can give me some insight. I've done some diagnostics, and I'd like your take...
- Nexus 7 3G, purchased a few weeks ago. 4.2.1, not rooted, stock charger and cable
- Battery life seems good, fully charges and discharges 'normally'
- I usually charge with the device powered off (ie: blocky battery icon in the middle of the screen).
However....
- On two occasions now, I've left it on the charger for a long time (>15 hours) and have come back to a dead device.
- Pressing the power button doesn't bring up the blocky battery icon.
- Holding the power button for 30+ seconds brings the device back back.
- It has otherwise never failed to boot properly during normal use.
Out of curiosity, I was wondering if there was something wrong with the charging process causing this, so
- I plugged the stock charger into my Kill-A-Watt last night to monitor the charging current.
- Even 8 hours after the device finished charging (via the blocky icon), the current never dropped to zero - it stuck around 10mA on the AC side (ie: ~1.2W).
- My first N7 (sent back for a bad speaker and dead pixels) went to zero after charging. My iPad does the same.
QUESTION(S):
I know modern LiPo batteries have internal circuitry to prevent overcharging, but does it sound like that circuitry might be defective on mine such that I should be worried about overcharging? Could that be the reason for my lockups?
I really don't want to go through the return process again if I don't have to. I'd rather just live with it if I can prevent damage by taking it off the charger when complete. Thoughts? Opinions? Have any of you done this test, and if so, does yours go to zero?
Thanks for any insight!

developer_john said:
However....
- On two occasions now, I've left it on the charger for a long time (>15 hours) and have come back to a dead device.
- Pressing the power button doesn't bring up the blocky battery icon.
- Holding the power button for 30+ seconds brings the device back back.
- It has otherwise never failed to boot properly during normal use.
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Click to collapse
That might be a possible cause... Leaving any device plugged in the charger for long periods of time is not recommended. Anyway have you tried charging the tablet with another charger with a higher output? If it refuses to turn on even after holding the power button for 30 seconds you might be able to "wake" it up by using a higher output charger. Thats what I did on my Nexus 7 when the battery level went too low.

cr0wnest said:
That might be a possible cause... Leaving any device plugged in the charger for long periods of time is not recommended. Anyway have you tried charging the tablet with another charger with a higher output? If it refuses to turn on even after holding the power button for 30 seconds you might be able to "wake" it up by using a higher output charger. Thats what I did on my Nexus 7 when the battery level went too low.
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Click to collapse
Hmmm...everything I've read has indicated that Lithium Ion/Polymer batteries can be left on a charger without damage since they have internal circuitry to prevent overcharging (although I realize a constant topping off is probably not wise in the long run). As for a charger with a higher output, I thought the stock charger was 2.1A....I've never heard of a 3A or 4A USB charger. Can you clarify what you mean?
Also, as I said, on the two occasions it has locked up, holding the power button has brought it back, so I'm not really asking about how to get it back if it locks up - I'm asking if the behavior (locking up, charge current not dropping to 0) is indicative of a battery that has faulty overcharge protection.
Thanks though!

The "charger" IC inside the N7 not only charges the battery but at the same time powers the device - it should allow use of a N7 with no or a faulty battery. I've never looked at the standby settings on the N7 but I would suggest that is where your 1W is going. The only info about the IC I know is http://www.summitmicro.com/prod_select/summary/SMB347/SMB347.htm
Added I think this is an identical TI version of the chip http://www.ti.com/lit/ds/slusaw5a/slusaw5a.pdf

peterk-1 said:
The "charger" IC inside the N7 not only charges the battery but at the same time powers the device - it should allow use of a N7 with no or a faulty battery. I've never looked at the standby settings on the N7 but I would suggest that is where your 1W is going. The only info about the IC I know is http://www.summitmicro.com/prod_select/summary/SMB347/SMB347.htm
Added I think this is an identical TI version of the chip http://www.ti.com/lit/ds/slusaw5a/slusaw5a.pdf
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Click to collapse
Thanks - that's good info. However, since I have been charging with the device off, it would seem to me that it shouldn't be drawing any standby current...unless just the act of charging puts the unit in a form of standby. It also still doesn't explain why my first unit went to 0A a while after charging completed, while this one doesn't. I'm now wondering if I may be looking at roundoff error. The resolution of the kill-a-watt is .01A - which is what I'm seeing. It could just be that both units drew some current after charge completion, but this one pulls marginally more.
So, my question still stands. Does anyone familiar with LiPo technology know if this sounds like my overcharge protection circuitry is faulty? Is it normal for a device that has completed charging to draw SOME current, and if so, how much? Would someone else with a Kill-A-Watt be willing to try this and let me know what you see?
Thanks again for the help guys...

Just in case anyone is still following this thread, I have some new info. I charged my N7 last night POWERED ON.....and after charging was complete, the AC current draw went to 0A. I'm starting to wonder now whether the 1.2W constant power I saw when charging powered off is the power needed to keep the charging circuitry alive while the tablet is powered off. When the device is powered on, maybe this circuitry is running off the battery allowing the AC draw to go to 0A. I have absolutely nothing to support this, so it's just a guess/hypothesis, but at least I know my N7 is behaving the same as my first one. I also loaded Simple Battery Logger while doing my last charge and all looks normal....it charged up to about 4.208V, indicated 'full', then the voltage start dropping off - which tells me that it stopped charging. It also maintained a temp of about 23C throughout the process. I'm running a battery test right now and it doesn't seem to have been damaged by my overnight charging episodes...if anything, the battery life is better than when I first got it.
I'm going to let it go here and assume all is well. If anyone does any experiments with theirs, I'd be interested in seeing the results.
Thanks again!

Need help troubleshooting, dead rk3066 tablet

Hello,
I need help with my new tablet.
Model is Allfine Fine10 Yoy.
Specs:
Rockchip RK3066, 1.6GHz, Cortex A9 dual core; GPU: Mali 400 MP4
Android 4.1
1GB (DDR3)
16GB Nand Flash
10.1 Inch / IPS
Battery: 7800mAh
It is not so old, about 5 months. Few days ago I have left it to charge overnight (it usually takes 4-5 hours to charge so I always charge it overnight) and in the morning it could not turn on. It is dead, no signs of life. I checked maybe it did not charge, so I changed power socket and tried again.
I can not charge it via USB so I can't test that.
There is not sign of life when connected to PC, adb list's no devices.
There is no sign of life after holding power/lock button for a long time and there is not signs after holding restart button.
It came factory rooted, I've never updated/flashed or anything.
I have not noticed any troubles so far, no lags, no freezing, no overheating.
Are you familiar with debug method for this kind of tablet?
What should I do, what test to make?
Can you help me debug this, please.
Thank you.

cheap china tablets are easy to open up. just pry the back cover off carefully and put a volt meter on the battery. its probably dead.
check your power supply first, it might have croaked too.

Would it be possible to run tablet with removed battery, straight off adapter to check is it working?

mrnjau said:
Would it be possible to run tablet with removed battery, straight off adapter to check is it working?
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Possibly, at least some part of startup.
Most device processors will start up if they notice power coming from somewhere.
At some point try will try to access the state and source of power.
If they notices that the battery is really dead (that is, the power is only from USB) they will shut down and go into charge-only mode.
It may be more likely that your battery is charged and the processor got wedged somehow.
Disconnect from USB, open the back, disconnect the battery and reconnect it.

Renate NST said:
Possibly, at least some part of startup.
Most device processors will start up if they notice power coming from somewhere.
At some point try will try to access the state and source of power.
If they notices that the battery is really dead (that is, the power is only from USB) they will shut down and go into charge-only mode.
It may be more likely that your battery is charged and the processor got wedged somehow.
Disconnect from USB, open the back, disconnect the battery and reconnect it.
Click to expand...
Click to collapse
Thank you for your reply,
I've precedeed as you sugested.
Solder is pretty hard on battery connection, so I unsoldered just one (negative wire, red one) and pluged it to charger and try to start it. I undsolderd just one because I don't want heat to ruin something and I guessed it should be enough to try this.
It still shows no signs of life.
However I've noticed something, when re-soldering red wire I have noticed that there is a spark when wire is near the solder point. So, there is some power in battery.
Any idea how to proceed? I still don't have multimeter to test battery voltage so that will have to wait.
Thanks once again.

Oh, sorry, I thought that the battery was on a connector.
That makes life easier than soldering.
The red wire(s) are always the positive.
The black wire(s) are always the negative (ground).
Any other color wires on a battery are thermistor, id sense or communication.
Yes, finding/borrowing a voltmeter is the next step.

Renate NST said:
Oh, sorry, I thought that the battery was on a connector.
That makes life easier than soldering.
The red wire(s) are always the positive.
The black wire(s) are always the negative (ground).
Any other color wires on a battery are thermistor, id sense or communication.
Yes, finding/borrowing a voltmeter is the next step.
Click to expand...
Click to collapse
Renate, I hope you still follow this topic.
I'm sorry for 2 months without updates, I've waited for some time for parts from China.
So, what have I done so far...
1) Get multimeter.
2) Test battery.
Battery is designated as 3.7V, however output is 4.15 - 4.16 V.
I've presumed this is fine.
3) Test the charger.
Charger is designated on 5V and 3A. I've tested voltage, it is fine. However ampers dance between 0.5A and 3.5A. I've presumed that charger is faulty, so I've ordered new one. Generic 5V, 3A charger.
4) Put it back together, re-solder the battery and connect charger. Test again.
Voltage on battery connectory is same as before - 4.15V.
After 20min there is no change in battery temperature (source: my fingers), however power jack where new charger is connected is getting warm, but not too warm.
Tried to power it on, no signs of life. Tried holding restart button for forewer, no sign of life.
I'm out of ideas.

3 Amps is a heck of a charger.
Where did that come from? Is it stock?
You have a little round coaxial connector for the charging input on the tablet?
There's no reason that it should be drawing 3 amps or anything getting warm.
The battery is fully charged.
There could be a high resistance in the battery protection module so that it looks charged but can't actually supply any current when called upon.
There's a USB connector on this too?
And nothing appears when you connect a USB cable to it?
I wouldn't expect ADB, but maybe a bootloader.
Run devmgmt.msc when plugging it in and see if anything at all shows up.

Renate NST said:
3 Amps is a heck of a charger.
Where did that come from? Is it stock?
You have a little round coaxial connector for the charging input on the tablet?
There's no reason that it should be drawing 3 amps or anything getting warm.
The battery is fully charged.
There could be a high resistance in the battery protection module so that it looks charged but can't actually supply any current when called upon.
There's a USB connector on this too?
And nothing appears when you connect a USB cable to it?
I wouldn't expect ADB, but maybe a bootloader.
Run devmgmt.msc when plugging it in and see if anything at all shows up.
Click to expand...
Click to collapse
Stock charger is 3A, so I bought with indetical specs. My research showed that a lot of chinese tabs use 3A chargers (Ainol Hero, etc..)
Yes, charger connector is 2.5mm "needle".
Some 30min after I posted this area around connector and speaker on motherboard got very very hot, I almost injured myself by touching it. So I've disconnected it.
No, nothing on USB. I've mentioned it in my first post, there are no signs of life on adb. Or "dmesg", which should list something even if device was bricked.

Um, are you sure that the polarity of the supply is correct?
For coaxial plugs the center is usually positive.
If it got that hot you probably have blown something.

Renate NST said:
Um, are you sure that the polarity of the supply is correct?
For coaxial plugs the center is usually positive.
If it got that hot you probably have blown something.
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Click to collapse
http://www.amazon.com/2000mah-Adapt...6-6172141?ie=UTF8&refRID=1AED4Q5XRX7QS8JJ91Y9
This is that kind of power connector, 2.5mm. Are we talking about the same thing? Is is possible for this kind of connectors to have non-standard polarity.
Maybe nothing is blown, I would smell that. Maybe there just hi resistance somewhere along the line.

Well, if it's the same charger and it used to charge then the polarity must be ok.
Still, something is not happy.
You should have been able to get it working with just the battery.
The DC input should not be getting hot.
I can only say so much from this distance.

Renate NST said:
Well, if it's the same charger and it used to charge then the polarity must be ok.
Still, something is not happy.
You should have been able to get it working with just the battery.
The DC input should not be getting hot.
I can only say so much from this distance.
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Click to collapse
I can't find any info on ampers and battery. I can't measure any amps coming out of battery, that's strange. I don't know much about this but should not battery put up some ampers?
Yeah, I understand that DC port should not get hot. Only 2 options.
1) Charger (the new one) is putting up too much electricity, to many amps that is.
2) There is something faulty on DC port or around it and causes too much resistance and thus heat.