[Q] Power down when charging stops?? - Nexus 7 Q&A, Help & Troubleshooting

I made a car dock for my Nexus 7 (2012, running SlimKat ROM, on Lollipop).
It works great, except that if I don't drive for 2 or 3 days the battery runs down to zero while it's sleeping.
Is there an app that will shut the tablet down (completely) when the charging current goes away (when the car turns off)?
I tried "Autosleeper", which claims to do it, but even if you set "power off" it only puts the tablet into sleep mode (at least on Lollipop).
Alternatively, is there a way to really minimize the power draw in sleep mode automatically (turn off all radios, timers, apps, etc. until it's woken up by power coming back to the USB port)?

** solved **
OK, I figured it out.
Autosleeper works fine (shuts down the tablet) if the tablet is rooted. Not otherwise.

** NOT solved **
I spoke too soon.
It works ONCE. If you boot the tablet, set Autosleeper to power off on loss of USB power, it'll do it once (and prompt for permission to root).
Even if you say "permission granted always", after it reboots it goes back to just sleeping, not power off.

Related

[Q] POWER RESET or UNKNOWN UPLOAD MODE

Anyone having boot problems?
Waiting the case, i have put my tab in his box moving from a place to another, when i took it i saw a green andoid image with the message "POWER RESET or UNKNOWN UPLOAD MODE".
Now it is blocked in this message state. Can't turn off, reboot ...use it...
Anyone know the way to reboot (key combination)? if galaxy tab has a recovery system? or something in order to resolve this problem?
Just to know, no root attempts, only some application normal installed from the market...
hi, i think if you press the power button and leave it pressed, it will reboot.
after the battery charge finished and the recharged all work fine...
i think the "block state" has been caused from the home+volume keys that probably were were pressed in the box..
it would be usefull to know these key-press effects
They are standard android combos. Google is your friend.
I stumbled across this screen while my Samsung SGH-I897 (Captivate) was powered down, hooked up to my PC using the USB cable and the battery was half way charged. I held down both the power and volume up buttons for a few seconds and got to this screen before the unit attempted to boot. It remained there until I held down the same key sequence for about 5-7 seconds. It's now back to a powered off state, still hooked up to my PC via the USB cable, and the display has the standard large battery icon showing it at about 50% charged. Leaving the Captivate idle will continue to charge my phone via USB (abeit slower than having it attached to the power adapter) and the screen shuts itself off. It practically looks like it's fully off or fully dead like this, but it's not.

Random reboots and other problems?

Hi All,
I've had my (entirely stock) tab for about 4 months, and my patience is wearing thinner and thinner with it.
Frequently - perhaps once a day, I will go to use the tab and find that it has turned itself off. The battery will not be flat; but it's randomly shut down. Most of the time it will restart ok.
However, sometimes - perhaps 1 in 3 times - it won't turn on. I end up holding the button down for ages, letting go, trying again. After about a minute of messing around, it will turn on. Again, the battery will not be flat.
Also, sometimes when using it, it will randomly "warm" reboot - that is, it will lock up for a few seconds, then give me the boot animation before restarting the UI. Athough this is usually a lot faster than a full boot from cold.
Sometimes when the thing is in standby - not being used - i will suddenly hear the sounds from the boot animation. I presume this is the same as the point immediately above, just when i'm not using it.
Does anyone else have these problems? i.e. does my tablet have a hardware fault, or is the tab10.1 just a poor quality product?
thanks
slip
There are about 3 threads going on regarding this. There is an issue with the power button on some older model. If you search you will find it, I just read it last night.
I had the deep sleep problem ( won't turn on after holding the pwr once to make it sleep ) a lot on 3.1 but on 3.2 I only have that problem when my tab is in it's keyboard dock.
Keyboard dock + sleep = generating that 'won't awake problem' but as mentioned, there are a few threads about this yeah.
ladybeefcake
Who can tell me or help me
usb charging on laptop is not working with galaxy task 13.1 Slim
Can not enable with Gscript an SU on , usb charging
ladybeefcake said:
Who can tell me or help me
usb charging on laptop is not working with galaxy task 13.1 Slim
Can not enable with Gscript an SU on , usb charging
Click to expand...
Click to collapse
Flash pershoots kernel

[XOOM 2] Charging LED and odd power behaviour...*UPDATE*

Gents,
I have just got a Xoom 2 16GB Wi-Fi only model and seem to be having a problem.
I have read the original Xoom tips & tricks thread and searched but want to clarify a few things...
On the Xoom2
1. The charging LED does not light. Apparently it only lights when the unit is powered off. Ok, I can accept that.
2. When plugged in, if I try to power my unit off it powers up again on its own.
I spoke to Motorola tech-support about this and they said that was "designed" behaviour. The unit will automatically power on when the charge level is above a certain threshold.
Is the above true? Does the unit have to be VERY low on battery before the LED will indicate that charging is taking place?
I'm rather confused as all of the above seems totally counter intuitive to me.
Any advice appreciated.
Yes you cannot charge the tablet while it is powered off, it will automatically turn on and charge.
Apparently they changed this in the latest software update but I have yet to test this out.
Sent from my Motorola Droid Xyboard 10.1 with Verizon 4G LTE
The behavior will change when you get the 3.2.2 update. There's a powered off charging mode for quick charging now.
Xoom 2 charging
Yes, my xoom 2 also turns on to charge! found this weird but it must be the case.
Hrm.
Ok so I've done more digging and it does say on the Moto website that the "on to charge" behaviour is normal.
I am keep to get mine updated to 3.2.2 however my "System Updates" option just tells me that my system is up to date despite being only 3.2
Furthermore, I had trouble powering my device up again. I had what seemed like problems straight out of the box but after speaking to tech support they told me to charge the unit for a while (like a few hours) and then give it a go.
I did this and still no joy. I called again and they asked me to try pushing and holding all three buttons (i.e. vol up, vol down and power) together for 15s.
After I did this the unit powered up, I managed to get through the setup procedures and have a little play.
Then I put the unit in my bag and left for home. I got home and the unit wouldn't power up. So I tried the reset and got presented with a funny menu (looked like a bootloader to me).
Not sure what I selected here but it booted albeit with some weird apps showing.
I rebooted again and now it seems fine but not sure it's actually charging!!!
I might have to send this unit back for a fresh one.
Ok,
I've narrowed down my problem. If the unit is plugged into the wall adapter it will charge and work as normal. If it enters standby mode the unit will power on when the power button is pressed
Great.
However, if the unit IS NOT plugged in and it enters standby the power button WILL NOT turn the screen back on. It will just sit there lifeless.
The only way to recover from this state is to "reboot" it by pressing and holding the 3b buttons (vol up, vol down and power) for something like 10-15 seconds until the bootloader menu is shown.
Here's the real kicker though, if the unit is on but SHUTDOWN using the power button pressing the power button subsequently WILL turn the unit back on (i.e. it will go through the boot process showing the Moto logo/circles animation).
But again, once powered on, if the unit enters standby the power button will not turn the screen back on.
What is going on here? Does it just sound like my unit is faulty and needs to be replaced?
Any help appreciated...
SF
Bump.
Anyone got ideas/suggestions regarding the power button/standby issue I am describing above???
have you fully charged it yet?
Yup.
I charged it for a good 8 hours + (overnight) and it still exhibited the same behaviour.
I think the power button is dodgy/intermittent and that is what is causing the issue.
Either way, I've RMAed the unit back to Expansys and am awaiting a replacement.

[Q] How to fix! Fire will not reboot. "green" power button led stuck on

Today, after I was done using my tablet, I shut it off and noticed it turned off but the green led portion of the power light is still on. Tablet will not respond to power on/off commands, nor can I gain access to it via adb.
I updated to the Energy™ -.¸¸.·´¯ ICS CM9 Kang ROM several days ago, there were no problems there as I have been using the rom for a couple of days now.
All I did was hold the power button down, select "Power down" option came up "this will shut down your tablet" I selected "ok" and that was that.
KFU shows it as offline, as does adb. Windows does not detect the device.
Mine had a similar experience, using AOKP ICS, I powered it off and about 18 hours later I tried to turn it on and got nothing. Turned out the battery was just dead, I think it may have locked up while powering down and killed the battery. I would try a few things:
1. Hold down the power button for 10+ seconds and see if you can get it to do a hard shutdown.
2. Plug it in to the charger and see what happens.
3. Leave it alone for a while and hope the battery dies and it may start up after that when plugged in.
I kind of feel stupid, why is it with technology us geeks start troubleshooting by skipping the simple solutions, like "is it plugged in" well today, holding down the power button for 20 seconds fixed the problem. She booted up and everything is back to normal.
Appreciate the fast reply!

[Q] N7 only detects power when diplay is on???

Hello! I am running cyanogenmod and Timur Rom on 2012 N7. I have tasker to detect power on and power off but here's my trouble..
The N7 will only detect power when the display is on!?!?!?!
If the display is turned off or times out or is locked and I give it power, the display doesnt turn back on automatically. I turn it on manually with the lock button on the side and the battery shows no charge coming through.
With the display still on, i unplug and plug the power back in and it works fine!
I tested it on the PC. PC detects the N7 fine and sees the HDD. Even with the display off, the PC will detect the N7 and I can explore folders but the N7 still receives no power until I manually turn the screen on and unplug and plug the charger back in!
This is preventing me from doing the car dash install because I cannot depend on the N7 to turn on display automatically because it does not detect power with screen off. Only with screen on!
I have went through all settings a million times, tried every 101 troubleshooting step, and I cannot figure it out.
Please, please, please help me figure this out. It's driving me crazy! :cyclops:

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