9742 Unusual Recovery Timeout

[tpaine]

This is my first chance to handle and use a 9742, and my impression is that it is a very nice tablet. This tablet belongs to my new neighbor and while troubleshooting, the tablet rebooted out of recovery after about a 2 minute timeout.

This tablet came to me for test with a completely dead battery, and the owner lost the charger. Plugged it in to usb and charged for several hours. The tablet boots and runs normally (wifi connects, able to browse and play video). But the setting page battery usage data is not available.

Factory reset the tab thru setting/backup and reset, During this reset, one can observe the green android robot, with the spinning wheel and it automatically reboots to system, but with the same symptom.

At this point, I turned tab off. Then manual boot to recovery. The stock recovery seems to flash by, but then, the green android robot appears with no text and a red triangle and exclamation point in the middle. Tried pinhole reset at this point to no avail. Tab simply restarts.

If pinhole reset is not pushed, after about 2 minutes in the recovery with the red triangle, the system reboots on its own.

I have 2 questions at this point. How can this problem be solved (no batt data) and is this related to gen4 recovery time limits.

I know cwm recovery would probably solve the problem, but he asked to keep it stock without even rooting.

 

[tpaine]

Here is a photo the recovery screen I described above. Any one seen this before? And the 2 minute timeout/reboot is unique.




Note the lack of text in the recovery screen.

Still researching this problem. My neighbor keeps this tab stock and lets his kids use it. Says the lack of playstore is a "feature" for him. That along with open DNS safe-surfing works for him and his kids. He controls any apps to be installed.

So if I can't fix this via stock, I may root and install cwm recovery. That will allow the reset of battery stats, and should fix the problem. Then I will return recovery to stock.

The question is, how to unroot? Removing su from /bin would be one step. Is there more to it?

 

[vampirefo.]

Unrooting is just removing the root files, and flashing stock recovery.

Sent from my SPH-D710 using Android Tablet

 

[tpaine]

Rooted, installed cwm recovery. No luck. Data reset and wiped battery stats. Same problem "battery usage data not available."

Reinstalled stock recovery, removed root files. 9742_root_recovery.zip is setup for easy return to stock. Generated system backup.

Looks like a h/w problem. Certainly a small feature probably not noticed. Too bad he doesn't want to mod, this baby is 500mb system partition.

Thanks for the info.

 

[mcclain_ts]

I think this might have something to do with the stock ICS rom. I read a few stating that there's possibly a "glitch" in the Android.

Here's one such article I read: (found at stackexchange.com)
Battery life cut in half recently - DrReadUsbStatus issue?

I think, maybe a better battery stats app might be downloaded/sideloaded.(since they opt out for gapps/play) I'm sure there's an APK for something that is compatible, and you don't have to get it from the PlayStore. I'll keep my eyes open/look for something for you to look over.(if I find anything decent)

-----------------------------------------------------------------------------------------------------------------------------

I can say I've seen it exactly as you described it on another 9742, so there's nothing wrong with your neighbor's Coby. Hope this helps.(smilz)

 

[mcclain_ts]

"Battery usage data not available", could be partly a Coby specific thing too, but I doubt it. I'm seeing plenty of other tablets with similar symptoms. I think something like this would help to see what's going on (more closely) with the battery, and to help with any rapid discharge.

It might be found outside PlayStore. It's called "BetterBatteryStats".

Hope you're having a good one!

Oh, isn't the 9740-8 almost the same? Except the processor is a Hitachi or similar? I think it depends on where/when it was made too. I THINK!LOL The 9740-8 I had was an AllWinner A10. Hope that helps too.(smilz)

 

[tpaine]

"Battery usage data not available", could be partly a Coby specific thing too, but I doubt it. I'm seeing plenty of other tablets with similar symptoms. I think something like this would help to see what's going on (more closely) with the battery, and to help with any rapid discharge.

Found a intermittant (aren't they the worst?) problem with digitizer, touch goes crazy with show touches on. maybe that's causing rapid discharge of the battery on this 9742. Sounds like a candidate for Travellers "clean the contacts on the cable and socket trick.

But it is only intermittant, and battery use when on a stand (no movement of digitizer) metering of battery charge % works fine. Just the details (screen, wifi, etc) are missing:






So its not a big problem. Like you say, it may be a bug. This is an early release, (3-14-2012). It might be somewhat "normal" as you say. The tablet can still be reset thru settings/backup/reset/reset

 

[vampirefo.]

That pick helps, that is a common problem with early releases of ICS.
To fix install a different Rom, I think the bug was found in settings app just replacing that might fix it.
If not then either custom Rom or later version stock Rom.
Sent from my SPH-D710 using Android Phone.

 

[tpaine]

It looks like the problem with no text in the recovery screen is somewhat normal for early gen3 tabs. While reading this post by traveller, the answer is to tap the back button to bring up the text:

http://www.androidtablets.net/forum...-do-i-factory-reset-my-tablet.html#post297292

Tested and it works. Thanks again Trav. The recovery timeout in a Gen3 coby is still unique.

 

[vampirefo.]

It looks like the problem with no text in the recovery screen is somewhat normal for early gen3 tabs. While reading this post by traveller, the answer is to tap the back button to bring up the text:

http://www.androidtablets.net/forum...-do-i-factory-reset-my-tablet.html#post297292

Tested and it works. Thanks again Trav. The recovery timeout in a Gen3 coby is still unique.

Yes I just switched the recoveries over to cwrm recovery so fast I didn't really notice.

 

[tpaine]

LOL, had to switch back to stock recovery to check it. Turns out, that's way my neighbor wanted it any way.