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3463
August 19th, 2017 13:00
Dell 7840 Battery and Power down Issues
I purchased a Dell 7840 tablet in March of 16 and have been experiencing a couple of issues. The first issue is that the tablet powers off well before it reaches 0%. I first noticed it when it hit 50% battery life, then 65%, now it is occurring at 75%. This started about a year after I purchased the device. I've tried various battery calibration reset techniques for Andrew but have not been successful. The second issue is that sometimes when I go to use the device it is completely powered off and has to do a complete reboot. I tried the battery diagnostics and it says the battery is good. I've seen similar issues posted on other threads but nothing conclusive. Does anyone know if fixes have been identified for these items?
patekatek
2 Posts
2
August 20th, 2017 02:00
Dell does not care about this problem. All you get is a runaround from their so called tech support group. Hundreds of people have this problem and perhaps a class action law suit would be needed to get them to respond to the problem. As you can probably guess, I have the same problem.
Dell-SreejithR
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3.4K Posts
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August 20th, 2017 20:00
Thank you for your message.
Has there been any recent software changes like installing games, anti-virus or updates?
Does this happen always or is it intermittent? Does the tablet charge go below 50 % or does it turn off @ 75%?
Does the device turn if ac adapter is plugged in & is the device charge is less than 50%?
Since the battery is over a year old, the warranty would be expired & there is nothing that will be done under warranty.
Have you tried to reset the device to check if the issue persists? If not, please back up data & then reset the device back to factory settings.
BJW125
6 Posts
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August 22nd, 2017 23:00
Hi Sreejith,
See next post.
Regards,
Brandon
BJW125
6 Posts
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August 22nd, 2017 23:00
Hi Sreejith,
Has there been any recent software changes like installing games, anti-virus or updates?
Brandon - Of course there have been updates and new programs that is part of the required functionality of the device. If it helps I can provide a list of software and versions. Are there known software conflicts that can cause this issue?
Does this happen always or is it intermittent? Does the tablet charge go below 50 % or does it turn off @ 75%?
Brandon - Right now this issues occurs every time the tablet gets to approximately 75% battery life. When I first noticed it the battery would like to around 50% before shutting down. When it turns off there are no warnings the device goes black without completing a proper shutdown sequence.
Does the device turn if ac adapter is plugged in & is the device charge is less than 50%?
Brandon - The device will not register less than 75% currently whether plugged in or not.
Since the battery is over a year old, the warranty would be expired & there is nothing that will be done under warranty.
Brandon - I would like help identifying what the problem is. If it is the battery, that would obviously be a design or manufacturing defect as I'm sure they were designed to last much longer. I would hope Dell would stand behind their products and identify a fix.
Have you tried to reset the device to check if the issue persists? If not, please back up data & then reset the device back to factory settings.
Brandon - This sounds like a disruptive and time consuming process, before I do this can you tell me if this has been know to fix this problem on other devices?
BJW125
6 Posts
0
August 23rd, 2017 00:00
Patekatek,
I certainly hope Dell comes through on this. I work for the company that supplied the processing chips for this particular device, and it disturbs me to see end consumer products fail like this. This is a beautiful tablet and should last much longer. I purchased on a credit card that doubles the mfg warranty and if needed I will put in a claim.
Brandon
BJW125
6 Posts
0
September 11th, 2017 19:00
I called up Dell today and they said it would be $19 to pay for a diagnosis. If it is a major problem like a motherboard or a LCD display it would be $259 to fix. If it is the battery it would cost $99 for a (refurbished) battery and $149 for support to install it. So apparently not only is the battery designed not to be replaced they aren't even manufacturing them anymore.
I asked about whether this could be fixed under warranty since the symptoms started before the warranty expired and the answer was no. They willing to help identify the issue or offer a fix without additional expenditure on my end. Unfortunately after being a faithful customer for many years this may be one of the last dell products I purchase.
DSysoletin
1 Message
0
September 30th, 2020 02:00
HI, BJW125!
It seems like we have a problem with the battery controller charge counter in our 7840's.
It counting charge inaccurately, and "thinks" that there is a lot of power in battery. If You'll install AIDA64 and check "Battery" tab, You'll probably see unreasonable high remaining charge counter. For example, I see "Remaining charge" 27739 mA*h, while new battery has only 5900 mA*h capacity. It seems like a bug in the controller...
Probably, fully discharging the battery can help here (fully discharging from battery controller's point of view, not from Android/tablet motherboard).
Maybe it can be done with connecting charger with some low current, starting tablet and, when tablet begins to boot, quickly disconnecting charger. When Android starts, tablet will turn off, but it will consume some power during startup. Probably, after some iterations, battery will fully drained and controller will reset remaining charge to zero.
I'll update you if I'll find a working solution.
Have a nice day, and sorry for necroposting