Zenithink Zepad C91 Andoid 4.03 Power down, and not switch on again

[Christos]

Hello
Had the same problem. Put a pin in the reset. Small hole on the bottom. Then do firm ware update- been fine since. Just need to get it to play bbc I player and then all sorted- Hope this helps-
Matt

Matt, thanks for your reply.

How am i going to do the firmware update since the device is not recognised by my laptop?

I connect the tablet to my laptop via USB but the device is not recognised...

Is there any other way around it?

Million thanks for your help!

 

[fatmatt]

Matt, thanks for your reply.

How am i going to do the firmware update since the device is not recognised by my laptop?

I connect the tablet to my laptop via USB but the device is not recognised...

Is there any other way around it?

Million thanks for your help!

You can down load the firmware from the zenithink site on to a micro SD card. I used the card in my mobile and used the phone to get it from the site onto the card. I then put the card into the micro sd slot on the pad and re booted. It automatically started the update- took about 30 - 60 mins I think and gave a % update when you pressed the on button. It has been completely fine since. Even took a soaking on friday, aired it for 36 hours and restarted it yesterday and still fine.
Any one got BBC I player working Yet??

Matt

 

[dealmaster]

You can down load the firmware from the zenithink site on to a micro SD card. I used the card in my mobile and used the phone to get it from the site onto the card. I then put the card into the micro sd slot on the pad and re booted. It automatically started the update- took about 30 - 60 mins I think and gave a % update when you pressed the on button. It has been completely fine since. Even took a soaking on friday, aired it for 36 hours and restarted it yesterday and still fine.
Any one got BBC I player working Yet??

Matt

Hi Matt,

Thanks much for sharing your tips here. A few clarifying questions for you:

1. When you say you had the same problem, was it as I described in detail above on 5/22?

2. If yes, then from what firmware (ROM) version - to - what firmware version did you update your ZT-282 C91 tablet with? Would be great if you can tell us the file size (MB) to be sure of the right firmware size. I believe the firmware version is only identifiable by navigating to mnt/flash directory and looking for ZT282_H3.....txt file using the File Browser.
As I noted, my current firmware version is already the latest version that Zenithink has released which is this one, so I wonder if re-flashing to the same firmware ver. would make any difference...
* ROM (firmware) ver in mnt/flash directory: ZT282_H3_1a_1GB_C91_Android4.0_0327_V1.16

3. When you did the microSD side load with the new firmware, did you do it with ZT-282 C91 turned ON or was it turned OFF? IF turned OFF, of course, as Christos pointed out above, the problem at hand is that the C91 will not turn on whatever you do (Camera + Power button, PIN hole Reset, or whatever way), so I suppose we'll have to wait UNTIL C91 is fully charged (Green LED) AND keep it turned OFF when we do this microSD firmware install.

4. AFTER you installed/updated the firmware, were you really able to turn ON the C91 at anytime, i.e. even when trying to reboot when it shutdown, when AC Charger is connected (low battery), or when it went into sleep? Did you notice anything not properly working after this firmware installation, besides BBC I player not working?

Thanks so much again for guiding us! I haven't tried re-installing the same firmware onto C91, but if you can answer / confirm the above questions, I'll definitely try and report back here my findings.

-dealmaster

 

[fatmatt]

Hello,
sorry i have not replied earlier, dont look in very often.

In answer to your questions

1. I do not think my problem was as bad as yours, as I was able to get it working using the reset button.

2. the firmware update is at - Zenithink

3. I inserted the sd card with the tablet shut down. i then pressed the camera button and the on button, it recognised the firmware on the SD card and it loads it. if you press the on button whilst it is updating it gives you a % report. I think it took about 30mins.

Before I had done the firmware update, when it went off and would not come on again, i restarted it with the reset button. - it doesn't work instantly, so just press it once, you can hear it click and leave it before trying the on button. I found once it had been reset I could turn it completely off and it would restart as it should. I think if the battery level got too low it would go into the stuck off scenario

4. It has been completely fine since. Turns on / off. reboots properly. No running problems at all.

I have noticed today it has a pink vertical line on the screen. i presume it is due to the water damage.

Hope this helps. If you can not get it to do the firmware update, can you send it back?

Matt

 

[Texano0038]

Hello,
sorry i have not replied earlier, dont look in very often.

In answer to your questions

1. I do not think my problem was as bad as yours, as I was able to get it working using the reset button.

2. the firmware update is at - Zenithink

3. I inserted the sd card with the tablet shut down. i then pressed the camera button and the on button, it recognised the firmware on the SD card and it loads it. if you press the on button whilst it is updating it gives you a % report. I think it took about 30mins.

Before I had done the firmware update, when it went off and would not come on again, i restarted it with the reset button. - it doesn't work instantly, so just press it once, you can hear it click and leave it before trying the on button. I found once it had been reset I could turn it completely off and it would restart as it should. I think if the battery level got too low it would go into the stuck off scenario

4. It has been completely fine since. Turns on / off. reboots properly. No running problems at all.

I have noticed today it has a pink vertical line on the screen. i presume it is due to the water damage.

Hope this helps. If you can not get it to do the firmware update, can you send it back?

Matt

Where exactly in the SD directory? I tried to put the unzipped folder on the main directory /sdcard/ ZT282_H3_1a_1GB..... BUT IT DOES NOT WORK

 

[fatmatt]

Where exactly in the SD directory? I tried to put the unzipped folder on the main directory /sdcard/ ZT282_H3_1a_1GB..... BUT IT DOES NOT WORK

Hello- are you trying to download the firmware onto the sd card using your tablet? I used the sd card in my phone to download it. Then transfered the card to my tablet.
From memory I just put it where it. Suggested. Sorry I am not being very helpful. I normally struggle with this sort of thing, but this seemed reasonably straight: forward.
Matt

 

[dealmaster]

Hello,
sorry i have not replied earlier, dont look in very often.

In answer to your questions

1. I do not think my problem was as bad as yours, as I was able to get it working using the reset button.

2. the firmware update is at - Zenithink

3. I inserted the sd card with the tablet shut down. i then pressed the camera button and the on button, it recognised the firmware on the SD card and it loads it. if you press the on button whilst it is updating it gives you a % report. I think it took about 30mins.

Before I had done the firmware update, when it went off and would not come on again, i restarted it with the reset button. - it doesn't work instantly, so just press it once, you can hear it click and leave it before trying the on button. I found once it had been reset I could turn it completely off and it would restart as it should. I think if the battery level got too low it would go into the stuck off scenario

4. It has been completely fine since. Turns on / off. reboots properly. No running problems at all.

I have noticed today it has a pink vertical line on the screen. i presume it is due to the water damage.

Hope this helps. If you can not get it to do the firmware update, can you send it back?

Matt

Hi Matt & everyone,

Thanks Matt for answering my questions, they're very helpful. While I have not yet tried to reinstall the same firmware version (0327 V1.16) on to my ZT-282 C91 via the SD card, I DO have very good news to share -- my C91 tablet is now powering on / off / rebooting just fine! Here's what I think may be the trick to resolving this issue:

1) Make sure to COMPLETELY DRAIN OUT THE BATTERY by leaving it UNUSED and UNCONNECTED to AC Power / Charger for AT LEAST 24 HOURS.

2) AFTER you confirm that C91 does NOT power on (zero battery), connect the AC Power adapter then IMMEDIATELY (after 3 seconds) push the Power Button. In my case, the C91 powered on right away! (with ~5% battery level shown) Now, if you only press the Power button for < 2 seconds, then C91 will briefly display %battery level then shut off again (normal), so be sure to press it for > 5 seconds to make it properly boot up (if so, you should see the "ZTPad" logo up for ~10 seconds before "android" logo starts flashing).

3) IF powering on at step 2) did not work for you, try to RESET the C91 via the pin hole like Matt mentioned, then wait for a few seconds before pushing the Power button for > 5 seconds. I think this now should make the C91 power up normally.

4) To confirm that everything works normally, after C91 powers up fully into the Android homescreen, press the Power button again for 3 seconds to "Power off - OK". After it's completely off, push the Power button again (w/ or w/o AC power connected) for ~5 seconds to reboot it. It should normally power on.

So, this is just my wild guess but I think what was going on is that at initial power up AFTER the firmware update (at factory or after upgrade), when battery is not "reset", the RAM seems to not properly loading the correct updated bootloader (perhaps it's still trying to load the older version bootloader cached in RAM). By draining the battery completely down to Zero, it effectively resets it, and RAM correctly loads up the right bootloader version going forward.

The funniest part is that I came across this workaround totally by luck -- I had gotten my laptop bag that had this C91 also in it locked up in an office building overnight when last I checked I only had ~30% battery left in it, so I could not retrieve it and connect the AC power charger until exactly 24 hours later by which time the battery was completely dried out (i.e. have been at 0% for probably 20+ hours). When I brought it back home, I tried the power button which confirmed it did not turn on, but connected it to AC power and 3 seconds later when I hit the power button, it magically POWERED ON (YES!) NORMALLY FOR THE FIRST TIME! Since then, I've tried powering it off & on a few times at different battery levels, and it's working w/o a hitch! I've even tried to let it drain the battery all the way down to 20% level and I can turn it off and reboot just fine w/o AC power, AND then let it drain down to ~10% level and it still does NOT power down but it's giving me a BATTERY TOO LOW warning -- Yay~! (it used to shut off at <30%) I'd then power it off, and then immediately after AC power is added, I can still reboot it w/o waiting to recharge!

Please spread the word to other forums where users are struggling with this same issue. I'd encourage everyone to try this trick and report back your findings to confirm or reject my workaround above. I hope this does prove the right resolution and let all you frustrated C91 users sleep better. Looking forward to hearing back from you guys!

 

[clarkchong]

I had the same problem as well. The only difference is that I dont get a green lamp after full charge.

How do I open the tablet to check the connector? Is something that even a non technician can do?

Thanks,

I am a non-tech person, but I fixed my wife's tablet myself. Hopefully this thread may be useful to you~ (scroll to the bottom)
http://www.androidtablets.net/forum...ay-problem-green-band-bottom-when-tilted.html

 

[Texano0038]

I was able to flash it, but the same problem persists. Shuts off and I am STILL unable to turn it ON after it goes to sleep . wHAT'S NEXT?

Hello- are you trying to download the firmware onto the sd card using your tablet? I used the sd card in my phone to download it. Then transfered the card to my tablet.
From memory I just put it where it. Suggested. Sorry I am not being very helpful. I normally struggle with this sort of thing, but this seemed reasonably straight: forward.
Matt

 

[Vanessa57]

mine dosent even get a red light or green nothin

 

[Vanessa57]

do i have a dead tablet i get nothin

 

[samy67]

do i have a dead tablet i get nothin

can you tell me your model of your charger?

it has to be 9V and 2000mA

 

[benadlam]

Once your tablet is on....

Install this - http://www.sendspace.com/file/36lsif

Open and allow it superuser permission. Turn the minimum frequency up one, make sure the max is set to max and change the governor to on demand (please tell me if it's already on on demand as it might need to be on performance i can't remember)

 

[osha966]

I have Zepad c91 tablet and ihave same problem. after the power down under 30%..it became dead. then i try to re install the upgrade firmware .but can not restart only blank screen with ztpad logo ... see pics of re install upgrade screen. please ..can you help me

 

[ilan316]

I tried dealmaster trick , not working.
tablet battery is drained I connected the AC Power adapter then IMMEDIATELY (after 3 seconds) pushed the power button.


still black screen