Long story short after not using my Universal for a while it now has this issue:
Only turns on when plugged into charger
Immediately shuts off when unplugged
When plugged into charger, red charger light is not lit
When plugged into USB, charging light flashes quickly and unit does not power on
I hard reset and no change
Under Settings>Power it shows Main Battery: Unknown
What can I do?
buy a new battery?
Ya that's, of course, what I figured. just making sure this was not a known issue of some sort.
...if the battery I ordered doesn't fix it I'm coming after you for the $2.60 it cost me.
uuu...me so scared
Cheers!
99% it is a battery issue...
Today my phone chrashed twice when starting navigation while on the car charger. Screen went black, battery charging icon appeared, red led showed. A second attempt gave the same result. I also noticed the LED shining red... was rather afraid. And decided to restart without the charger, start navigation, and no crash.
After unplugging the charger, the screen stayed on the battery icon for a while. I could reboot the phone with the power button.
It woked okay a few times before but maybe the battery charge state was different, or I started navigation before plugging the charger in.
So, I won't use that charger (Samsung CAD300UBE rated at 5V 700mA) again. But why would it crash? The phone running on just charger power (which is insufficient) and crashing - perhaps to prevent damaging the battery with shallow charge cycles? I estimate the charge left when this happened at 80%.
So be careful which charger you use. Does anyone have a similar experience?
Im having same issue, but my phone wont boot up.
Any fix?
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.
Click to expand...
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.
Click to expand...
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
Click to expand...
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!
Hi everyone,
My Photon Q was probably about 30% charge when I last checked with it on. An hour or 2 later it was a little warm and was off. So I went to charge it using the car charger with 500mah charge rate. I came back about an hour later and the phone was really hot and no charging screen so I unplugged it. The green led light is lit when the phone is plugged in.
I tried holding the power button and volume down button, but it won't boot. If I have the usb charging cable plugged in from a PC or charger adapter when pressing those buttons, the green light will flicker off for a fraction of a second.
I then proceeded to dismantling the phone as I suspect a battery issue and the one in this phone is stupidly non-removable. After taking the back cover off, I tested the battery posts and received 0 volts. I still don't know if the battery caused the drain or if there's a short in the phone. I then took off the inside cover that holds the battery in. A few T5 screws later and the battery was removed. I connected the battery to some AA batteries in series to see if I could get a charge. A few hours later I got it up to 3 volts which held for several hours. So I connected it to a few more AA batteries in series to try and raise the voltage. I got it up to 3.67 volts and the battery is listed at 3.7 volts.
A day later and the voltage is still at 3.67 volts so I put the battery in the phone. I went to try and power it on, but nothing. I then connected it to a usb cord and received the slow flashing red led light a couple times before switching to green. The battery started getting warm again connected to the usb charger. After 20 minutes it was approaching hot so I unplugged the USB. The battery read 3.54 volts. 30 minutes later, 0 volts again.
Does anyone know what the actual voltage range is for this phone, as my old Samsung M320 is also 3.7 volts, but when testing the battery I get 4.10 volts? I heard it's pretty specific on minimum voltage. Any ideas for a temporary battery or way to boot the phone before spending $50 on a replacement battery and then find out there's a short in the phone. Is there another key combination to boot the phone, I'm trying to boot it to at least get my pictures and other data off it.
Thanks a lot in advance
Matt
Not the battery, seems to be an electrical short but where
I bought a new battery for the phone which had a 0 volt charge when I received it. I tried putting it in the phone as is to use the phone charger to charge it, but got nothing. So I charged it using 2, then 3 and then 4 AA batteries in series to get it up to 3.7 volts. I then put the battery in the phone and noticed the 2 large chips and the chip centered above them located by the camera get a little hot. I tried with the charger connected and not connected, but same thing. Power button doesn't turn the phone on. Just the green led lit when the USB power cable is attached. So now it seems there must be a short in the phone. Anyone know where I can look to check for a short, blown resistor or something in this phone? Or at least where the rom chip is located so maybe I can turn it into a usb drive to get my data at the least.
And sorry about the double post. I didn't receive any replies in the other section and I really need to get some data off the phone. Seemed the hardware section would be the place to check. Tree fell on the house and pictures before the tree was removed were taken with the phone which of course ironically stopped working right after.
The other day, my A500 started doing something weird during charging. when plugged in, it shows as charging via the hardware light AND the os itself. But, it wont charge. The only plus side here is that it will hold what it has while plugged in. I have it holding steady at 14%. Firstly, I tested the charger and it puts out a solid 12.0-12.1 volts, so that is fine. I have disassembled the tablet and checked all leads from the 12v in plug and all are fine and reading 12v at the board connection point. Inspection of battery shows no loose wires, and also has no bloat or noticeable issues. I have blown it all out and cleaned with 95% alcohol. All have no effect. SO, on to possible software issues. What can I check for here? Possible bootloader or other software failure? Any ideas would be greatly appreciated. Thanks.