Problem with Zenithink c91 with touch screen

sob2012

Member
Jun 20, 2012
2
0
Hi everyone !

I have a tablet pc Zenithink c91 and i was happy for a 1 month.
Some day I turn on the tablet and the touch screen don´t work. I need to connect a usb mouse for work with the table.

I reset a tablet, use de option "restore factory settings" and the problem is the same..


Someone can help me??..
 
Hi !

wich version of the Zenithink have you? if it's the 3a , go to Zenithink, download the latest roms.
when it done, you will have a folder name ""touch_firmware_for_3a", copy past all the file to the zt-update repository and flash your tablet

it will be ok :)
 
Hi !

wich version of the Zenithink have you? if it's the 3a , go to Zenithink, download the latest roms.
when it done, you will have a folder name ""touch_firmware_for_3a", copy past all the file to the zt-update repository and flash your tablet

it will be ok :)


Hi even I am facinng the same issue with my tablet, I hope you could help, I have a 2A version, and I also tried flashing my tablet by load the updated software from Zenithink website, but still I am facing the same issue, even I use usb mouse. Please help me. I even tried calibrating the touchscreen by pressing and holding the camera button, but nothing works...........
 
Hi even I am facinng the same issue with my tablet, I hope you could help, I have a 2A version, and I also tried flashing my tablet by load the updated software from Zenithink website, but still I am facing the same issue, even I use usb mouse. Please help me. I even tried calibrating the touchscreen by pressing and holding the camera button, but nothing works...........

Hi the solution i ve done is for the 3a model.

for your model i can't really help you.

try to reflash your tablet again and again with different roms but still care for the 2n model.

did you tried the android 2.3 version instead of ics 4.0.3?
 
Me too.

My screen stopped working after 3 weeks and after a full charge.

The touchscreen and the 4 side "buttons" are completely inert. CapTouch completely useless as Camera button as well.

I don't know if the problem is hardware or software:
ie someone has successfully installed the latest firmware against this problem ?

Thanks in advance
 
Me too.

My screen stopped working after 3 weeks and after a full charge.

The touchscreen and the 4 side "buttons" are completely inert. CapTouch completely useless as Camera button as well.

I don't know if the problem is hardware or software:
ie someone has successfully installed the latest firmware against this problem ?

Thanks in advance

have you reset the tablet?
 
yes...but without result.


I was wondering if anyone has installed the latest firmware (July) to fix it.

I'm afraid same problem here. I must plug USB mouse in order to turn it off properly. First I tried by reseting then I installed latest firmware from Zenithink. Finally I checked touch screen connections inside. Nothing worked, capacitive screen is gone. Yesterday I contacted someone experiencing that problem too. He's even published on Youtube as an evidence for Chinese dealer:



Actually he said it's capacitive screen failure, nothing to fix. Tt should be serviced or sent it back to China. Do you agree?
 
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I'm afraid same problem here. I must plug USB mouse in order to turn it off properly. First I tried by reseting then I installed latest firmware from Zenithink. Finally I checked touch screen connections inside. Nothing worked, capacitive screen is gone. Yesterday I contacted someone experiencing that problem too. He's even published on Youtube as an evidence for Chinese dealer:



Actually he said it's capacitive screen failure, nothing to fix. Tt should be serviced or sent it back to China. Do you agree?


YES, there's nothing to do ... I'll send it for warranty replacement.

I suspect that the heat of the components is part of this fault ...:confused:
 
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Hi,
I have the same problem.
I tried to install latest firmware but nothing. Indeed, I was not able to find a reset button on my C91 Upgrade..
Anyway, did you finally send it back to China? Do you know how long will it take? Thanks!
 
It appears many people have developed this problem. The touch screen on my Zenithink ZT-280 C91 3a version makes random selections of icons several times a second. Either the software and/or the hardware that manages the capacitive touch screen is causing the problem. This started with an occasional jitter. With an update to the latest version of Android ICS which I had hoped would stop the problem, the tablet has become unusable. I have had the unit since March and this is a problem that happened over the past two weeks.
I am a former embedded microprocessor development engineer, so I am quite used to debugging hardware and working alongside software developers.

This erratic behavior happens with the charger or without the charger plugged in. I see some people have problems with the charger and when the change the charger the problem goes away. (That is a power supply noise problem and is not the exact issue I am seeing).

I used the firmware from

http://www.zenithink.com/Eproducts_C91.php?download

I have flashed the latest version of ICS (314 I believe ) from Zenithink.com, then flashed the patch that is actually supposed to help jitter specifically happening on the 3a version of the ZT-280 C91 and even flashed an earlier non ICS version I tried an older version of Android. The Version 2.3, 0217 version. There is so much jitter on the screen in all cases that the tablet is unusable. I opened the unit and reseated the cables without improvement. Even when I plug in a USB keyboard, I have random selections made on the screen.

Is there a way in addition to changing the version of operating system where I can perform a master reset and start all over? If so, what is the procedure? I suspect it is a hardware problem. Anything else I can try? As one poster asked, How do you reset and start over? I have not spotted instructions on that.
 
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Hi the solution i ve done is for the 3a model.

for your model i can't really help you.

try to reflash your tablet again and again with different roms but still care for the 2n model.

did you tried the android 2.3 version instead of ics 4.0.3?


I loaded 4.0 version and again loaded the 2.3 version the problem is same, I am not sure how to reflash tablet using diffent rom....can you tell me how to do it, do you think it might be a hardware issue with the touch screen, may be the cable inside has some issue....I am not sure
 
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